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Desale SE, Chidambaram H, Chinnathambi S. Biochemical and Biophysical Characterization of Tau and α-Linolenic Acid Vesicles In Vitro. Methods Mol Biol 2024; 2754:193-203. [PMID: 38512668 DOI: 10.1007/978-1-0716-3629-9_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Alzheimer's disease (AD) is characterized by the abnormal accumulation of disordered protein, that is, extracellular senile plaques of amyloid-β (Aβ) and intracellular neurofibrillary tangles of Tau. Tau protein has gained the attention in recent years owing to the ability to propagate in a "prion-like" nature. The disordered protein Tau possesses a high positive charge, which allows its binding to anionic proteins and factors. The native disorder of proteins attends the β-sheet structure from its random-coiled conformation upon charge compensation by various polyanionic agents such as heparin, RNA, etc. Anionic lipids such as arachidonic acid (AA) and oleic acid (OA) are also one of the factors which can induce aggregation of Tau in physiological conditions. The free units of Tau protein can bind to lipid membranes through its repeat domain (RD), the anionic side chains of the membrane lipids induce aggregation of Tau by reducing the activation barrier. In this study, we investigated the role of α-linolenic acid (ALA) as an inducing agent for Tau aggregation in vitro conditions. Omega-3 fatty acids bear a capacity to reduce the pathology of Tau by downregulating the Tau phosphorylation pathway. We have studied by using various biochemical or biophysical methods the potency of ALA as an aggregating agent for Tau. We have implemented different techniques such as SDS-PAGE, transmission electron microscopy, CD spectroscopy to evaluated higher-order aggregates of Tau upon induction by ALA.
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Affiliation(s)
- Smita Eknath Desale
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, Maharashtra, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Hariharakrishnan Chidambaram
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, Maharashtra, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, Maharashtra, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India.
- Department of Neurochemistry, National Institute of Mental Health and Neuro Sciences (NIMHANS), Institute of National Importance, Bangalore, Karnataka, India.
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Wang C, Terrigno M, Li J, Distler T, Pandya NJ, Ebeling M, Tyanova S, Hoozemans JJM, Dijkstra AA, Fuchs L, Xiang S, Bonni A, Grüninger F, Jagasia R. Increased G3BP2-Tau interaction in tauopathies is a natural defense against Tau aggregation. Neuron 2023; 111:2660-2674.e9. [PMID: 37385246 DOI: 10.1016/j.neuron.2023.05.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 02/21/2023] [Accepted: 05/31/2023] [Indexed: 07/01/2023]
Abstract
Many RNA-binding proteins (RBPs), particularly those associated with RNA granules, promote pathological protein aggregation in neurodegenerative diseases. Here, we demonstrate that G3BP2, a core component of stress granules, directly interacts with Tau and inhibits Tau aggregation. In the human brain, the interaction of G3BP2 and Tau is dramatically increased in multiple tauopathies, and it is independent of neurofibrillary tangle (NFT) formation in Alzheimer's disease (AD). Surprisingly, Tau pathology is significantly elevated upon loss of G3BP2 in human neurons and brain organoids. Moreover, we found that G3BP2 masks the microtubule-binding region (MTBR) of Tau, thereby inhibiting Tau aggregation. Our study defines a novel role for RBPs as a line of defense against Tau aggregation in tauopathies.
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Affiliation(s)
- Congwei Wang
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland.
| | - Marco Terrigno
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Juan Li
- School of Life Sciences, University of Science and Technology of China, 230026 Anhui, China
| | - Tania Distler
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Nikhil J Pandya
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Martin Ebeling
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Stefka Tyanova
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Jeroen J M Hoozemans
- Department of Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, 1081 HV Amsterdam, the Netherlands
| | - Anke A Dijkstra
- Department of Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, 1081 HV Amsterdam, the Netherlands
| | - Luisa Fuchs
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Shengqi Xiang
- School of Life Sciences, University of Science and Technology of China, 230026 Anhui, China
| | - Azad Bonni
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Fiona Grüninger
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - Ravi Jagasia
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland.
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Dubey T, Kushwaha P, Thulasiram HV, Chandrashekar M, Chinnathambi S. Bacopa monnieri reduces Tau aggregation and Tau-mediated toxicity in cells. Int J Biol Macromol 2023; 234:123171. [PMID: 36716837 DOI: 10.1016/j.ijbiomac.2023.123171] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/20/2022] [Accepted: 01/03/2023] [Indexed: 01/30/2023]
Abstract
Alzheimer's disease is a neurodegenerative disease characterized by progressive memory loss and behavioral impairments. In the present study, the ethanolic extract of Bacopa monnieri was studied for its potency to inhibit Tau aggregation and rescuing of the viability of Tau-stressed cells. Bacopa monnieri was observed to inhibit the Tau aggregation in vitro. The cells exposed to Bacopa monnieri were also observed to have a low level of ROS and caspase-3 activity. The immunoblot and immunofluorescence analysis showed that Bacopa monnieri acts as an antioxidant and restored the Nrf2 levels in Neuro2a cells. Bacopa monnieri treatment to Neuro2a cells was observed to reduce the phospho-Tau load in formaldehyde-stressed cells. Furthermore, the treatment of Bacopa monnieri reduced the phosphorylation of GSK-3β in formaldehyde-stressed cells. Ran and NUP358 are the key proteins involved in nuclear transport. It was observed that formaldehyde treatment impaired the nuclear transport by missorting the NUP358 arrangement in Neuro2a cells. On the contrary, Bacopa monnieri treatment restored the NUP358 arrangement in cells. The overall results of the present study suggested that Bacopa monnieri could be considered a potent herb against Tau phosphorylation and Tau aggregation, which projects it as a promising formulation for Alzheimer's disease.
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Affiliation(s)
- Tushar Dubey
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Preeti Kushwaha
- Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India
| | - H V Thulasiram
- Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
| | - Madhura Chandrashekar
- The School of Bioengineering Sciences and Research, Maharasthra Institute of Technology, Loni Kalbhor, 412201 Pune, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; Department of Neurochemistry, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bangalore 560029, Karnataka, India.
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Ainani H, Bouchmaa N, Ben Mrid R, El Fatimy R. Liquid-liquid phase separation of protein tau: An emerging process in Alzheimer's disease pathogenesis. Neurobiol Dis 2023; 178:106011. [PMID: 36702317 DOI: 10.1016/j.nbd.2023.106011] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 01/04/2023] [Accepted: 01/21/2023] [Indexed: 01/24/2023] Open
Abstract
Metabolic reactions within cells occur in various isolated compartments with or without borders, the latter being known as membrane-less organelles (MLOs). The MLOs show liquid-like properties and are formed by a process known as liquid-liquid phase separation (LLPS). MLOs contribute to different molecules interactions such as protein-protein, protein-RNA, and RNA-RNA driven by various factors, such as multivalency of intrinsic disorders. MLOs are involved in several cell signaling pathways such as transcription, immune response, and cellular organization. However, disruption of these processes has been found in different pathologies. Recently, it has been demonstrated that protein aggregates, a characteristic of some neurodegenerative diseases, undergo similar phase separation. Tau protein is known as a major neurofibrillary tangles component in Alzheimer's disease (AD). This protein can undergo phase separation to form a MLO known as tau droplet in vitro and in vivo, and this process can be facilitated by several factors, including crowding agents, RNA, and phosphorylation. Tau droplet has been shown to mature into insoluble aggregates suggesting that this process may precede and induce neurodegeneration in AD. Here we review major factors involved in liquid droplet formation within a cell. Additionally, we highlight recent findings concerning tau aggregation following phase separation in AD, along with the potential therapeutic strategies that could be explored in this process against the progression of this pathology.
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Affiliation(s)
- Hassan Ainani
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Najat Bouchmaa
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Reda Ben Mrid
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Rachid El Fatimy
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco.
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Batenburg KL, Sestito C, Cornelissen-Steijger P, van Weering JRT, Price LS, Heine VM, Scheper W. A 3D human co-culture to model neuron-astrocyte interactions in tauopathies. Biol Proced Online 2023; 25:4. [PMID: 36814189 PMCID: PMC9948470 DOI: 10.1186/s12575-023-00194-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 02/17/2023] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND Intraneuronal tau aggregation is the major pathological hallmark of neurodegenerative tauopathies. It is now generally acknowledged that tau aggregation also affects astrocytes in a cell non-autonomous manner. However, mechanisms involved are unclear, partly because of the lack of models that reflect the situation in the human tauopathy brain. To accurately model neuron-astrocyte interaction in tauopathies, there is a need for a model that contains both human neurons and human astrocytes, intraneuronal tau pathology and mimics the three-dimensional architecture of the brain. RESULTS Here we established a novel 100-200 µm thick 3D human neuron/astrocyte co-culture model of tau pathology, comprising homogenous populations of hiPSC-derived neurons and primary human astrocytes in microwell format. Using confocal, electron and live microscopy, we validate the procedures by showing that neurons in the 3D co-culture form pre- and postsynapses and display spontaneous calcium transients within 4 weeks. Astrocytes in the 3D co-culture display bipolar and stellate morphologies with extensive processes that ensheath neuronal somas, spatially align with axons and dendrites and can be found perisynaptically. The complex morphology of astrocytes and the interaction with neurons in the 3D co-culture mirrors that in the human brain, indicating the model's potential to study physiological and pathological neuron-astrocyte interaction in vitro. Finally, we successfully implemented a methodology to introduce seed-independent intraneuronal tau aggregation in the 3D co-culture, enabling study of neuron-astrocyte interaction in early tau pathogenesis. CONCLUSIONS Altogether, these data provide proof-of-concept for the utility of this rapid, miniaturized, and standardized 3D model for cell type-specific manipulations, such as the intraneuronal pathology that is associated with neurodegenerative disorders.
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Affiliation(s)
- Kevin L. Batenburg
- grid.12380.380000 0004 1754 9227Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience - Neurodegeneration, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Claudia Sestito
- Crown Bioscience Netherlands B.V. (Formerly OcellO B.V.), Leiden, The Netherlands ,grid.484519.5Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Child and Adolescent Psychiatry, Amsterdam Neuroscience, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Paulien Cornelissen-Steijger
- grid.484519.5Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Child and Adolescent Psychiatry, Amsterdam Neuroscience, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands ,grid.484519.5Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Jan R. T. van Weering
- grid.12380.380000 0004 1754 9227Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience - Neurodegeneration, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands ,grid.484519.5Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Human Genetics, Amsterdam Neuroscience - Neurodegeneration, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Leo S. Price
- Crown Bioscience Netherlands B.V. (Formerly OcellO B.V.), Leiden, The Netherlands
| | - Vivi M. Heine
- grid.484519.5Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Child and Adolescent Psychiatry, Amsterdam Neuroscience, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands ,grid.484519.5Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Wiep Scheper
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience - Neurodegeneration, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands. .,Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Human Genetics, Amsterdam Neuroscience - Neurodegeneration, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands.
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Akbari V, Mohammadi S, Mehrabi M, Ghobadi S, Farrokhi A, Khodarahmi R. Investigation of the role of prolines 232/233 in RTPPK motif in tau protein aggregation: An in vitro study. Int J Biol Macromol 2022; 219:1100-1111. [PMID: 36049563 DOI: 10.1016/j.ijbiomac.2022.08.160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 07/26/2022] [Accepted: 08/23/2022] [Indexed: 11/18/2022]
Abstract
Disease-related tau protein in Alzheimer's disease is hyperphosphorylated and aggregates into neurofibrillary tangles. The cis-proline isomer of the pSer/Thr-Pro sequence has been proposed to act as a precursor of aggregation ('Cistauosis' hypothesis), but this aggregation scheme is not yet entirely accepted. Hence to investigate isomer-specific-aggregation of tau, proline residues at the RTPPK motif were replaced by alanine residues (with permanent trans configuration) employing genetic engineering methods. RTPAK, RTAPK, and RTAAK mutant variants of tau were generated, and their in vitro aggregation propensity was investigated using multi-spectroscopic techniques. Besides, the cell toxicity of oligomers/fibrils was analyzed and compared to those of the wild-type (WT) tau. Analyses of mutant variants have shown to be in agreement (to some degree) to the theory of the 'cistauosis' hypothesis. The results showed that the trans isomer in the 232-rd residue (P232A mutant rather than P233A) had reduced aggregation propensity. However, this study did not illustrate any statistically significant difference between the wild and the mutant protein aggregations concerning cell toxicity.
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Affiliation(s)
- Vali Akbari
- Department of Biology, Faculty of Sciences, Razi University, Kermanshah, Iran; Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences (KUMS), Kermanshah, Iran
| | - Soheila Mohammadi
- Nano Drug Delivery Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Masomeh Mehrabi
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences (KUMS), Kermanshah, Iran
| | - Sirous Ghobadi
- Department of Biology, Faculty of Sciences, Razi University, Kermanshah, Iran.
| | - Alireza Farrokhi
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences (KUMS), Kermanshah, Iran
| | - Reza Khodarahmi
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences (KUMS), Kermanshah, Iran; Department of Pharmacognosy and Biotechnology, Faculty of Pharmacy, Kermanshah University of Medical Sciences (KUMS), Kermanshah, Iran.
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Annadurai N, Malina L, Malohlava J, Hajdúch M, Das V. Tau R2 and R3 are essential regions for tau aggregation, seeding and propagation. Biochimie 2022; 200:79-86. [PMID: 35623497 DOI: 10.1016/j.biochi.2022.05.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 05/20/2022] [Accepted: 05/20/2022] [Indexed: 12/28/2022]
Abstract
Tauopathies are characterised by intracellular deposits of fibrillar tau tangles. However, the interneuronal spread of pathological tau species precedes the development of major tau burdens. Two amyloid motifs, VQIINK in repeat 2 and VQIVYK in repeat 3, of tau repeat domain, assemble into β-sheet-rich fibrils on their own but alone do not form seed-competent fibrils. In contrast, the entire R3 region self-aggregates and forms seed-competent fibrils. Our study aimed to identify the minimal regions in the tau repeat domain that define seeding and its impact on intracellular tau phosphorylation and aggregation. Using peptides of individual repeats, we show that R2, like R3, forms seed-competent fibrils when assembled in the presence of heparin. However, R3, but not R2, forms seed-competent fibrils when assembled without heparin, even though both R2 and R3 have identical N-terminal hexapeptide and cysteine residue sequences. Moreover, cysteine to alanine substitution in R3 abrogates its self-aggregation and seeding potency. Tau RD P301S biosensor cells and Tau P301L (0N4R)-expressing HEK293 cells seeded with R2 and R3 fibrils show the induction of pathological phosphorylation of tau at Ser262/Ser396/Ser404 positions and oligomerisation of native tau. Protein fractions of biosensor cells seeded with R2 and R3 fibrils reseed endogenous tau aggregation when introduced into a fresh set of biosensor cells. Our findings suggest that R3 may be the minimal region for pathological seed generation under physiological conditions, whereas R2 might need polyanionic cofactors to generate pathogenic seeds. Lastly, R2 and R3 fibrils induce template-induced misfolding and pathological hyperphosphorylation of intracellular tau, making intracellular tau seed-competent.
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Affiliation(s)
- Narendran Annadurai
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 1333/5, 77900, Olomouc, Czech Republic
| | - Lukáš Malina
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacký University in Olomouc, Olomouc, Czech Republic
| | - Jakub Malohlava
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacký University in Olomouc, Olomouc, Czech Republic
| | - Marián Hajdúch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 1333/5, 77900, Olomouc, Czech Republic; Czech Advanced Technologies and Research Institute (CATRIN), Institute of Molecular and Translational Medicine, Palacký University Olomouc, Krizkovskeho 511/8, 77900, Olomouc, Czech Republic
| | - Viswanath Das
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 1333/5, 77900, Olomouc, Czech Republic; Czech Advanced Technologies and Research Institute (CATRIN), Institute of Molecular and Translational Medicine, Palacký University Olomouc, Krizkovskeho 511/8, 77900, Olomouc, Czech Republic.
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Kolay S, Vega AR, Dodd DA, Perez VA, Kashmer OM, White CL, Diamond MI. The dual fates of exogenous tau seeds: lysosomal clearance vs. cytoplasmic amplification. J Biol Chem 2022; 298:102014. [PMID: 35525272 PMCID: PMC9163595 DOI: 10.1016/j.jbc.2022.102014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 04/29/2022] [Accepted: 04/30/2022] [Indexed: 11/30/2022] Open
Abstract
Tau assembly movement from the extracellular to intracellular space may underlie transcellular propagation of neurodegenerative tauopathies. This begins with tau binding to cell surface heparan sulfate proteoglycans, which triggers macropinocytosis. Pathological tau assemblies are proposed then to exit the vesicular compartment as “seeds” for replication in the cytoplasm. Tau uptake is highly efficient, but only ∼1 to 10% of cells that endocytose aggregates exhibit seeding. Consequently, we studied fluorescently tagged full-length (FL) tau fibrils added to native U2OS cells or “biosensor” cells expressing FL tau or repeat domain. FL tau fibrils bound tubulin. Seeds triggered its aggregation in multiple locations simultaneously in the cytoplasm, generally independent of visible exogenous aggregates. Most exogenous tau trafficked to the lysosome, but fluorescence imaging revealed a small percentage that steadily accumulated in the cytosol. Intracellular expression of Gal3-mRuby, which binds intravesicular galactosides and forms puncta upon vesicle rupture, revealed no evidence of vesicle damage following tau exposure, and most seeded cells had no evidence of endolysosome rupture. However, live-cell imaging indicated that cells with pre-existing Gal3-positive puncta were seeded at a slightly higher rate than the general population, suggesting a potential predisposing role for vesicle instability. Clearance of tau seeds occurred rapidly in both vesicular and cytosolic fractions. The lysosome/autophagy inhibitor bafilomycin inhibited vesicular clearance, whereas the proteasome inhibitor MG132 inhibited cytosolic clearance. Tau seeds that enter the cell thus have at least two fates: lysosomal clearance that degrades most tau, and entry into the cytosol, where seeds amplify, and are cleared by the proteasome.
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Affiliation(s)
- Sourav Kolay
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas
| | - Anthony R Vega
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas
| | - Dana A Dodd
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas
| | - Valerie A Perez
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas
| | - Omar M Kashmer
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas
| | - Charles L White
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas
| | - Marc I Diamond
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas.
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Limorenko G, Lashuel HA. To target Tau pathologies, we must embrace and reconstruct their complexities. Neurobiol Dis 2021; 161:105536. [PMID: 34718129 DOI: 10.1016/j.nbd.2021.105536] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/15/2021] [Accepted: 10/21/2021] [Indexed: 10/20/2022] Open
Abstract
The accumulation of hyperphosphorylated fibrillar Tau aggregates in the brain is one of the defining hallmarks of Tauopathy diseases, including Alzheimer's disease. However, the primary events or molecules responsible for initiation of the pathological Tau aggregation and spreading remain unknown. The discovery of heparin as an effective inducer of Tau aggregation in vitro was instrumental to enabling different lines of research into the role of Tau aggregation in the pathogenesis of Tauopathies. However, recent proteomics and cryogenic electron microscopy (cryo-EM) studies have revealed that heparin-induced Tau fibrils generated in vitro do not reproduce the biochemical and ultrastructural properties of disease-associated brain-derived Tau fibrils. These observations demand that we reassess our current approaches for investigating the mechanisms underpinning Tau aggregation and pathology formation. Our review article presents an up-to-date survey and analyses of 1) the evolution of our understanding of the interactions between Tau and heparin, 2) the various structural and mechanistic models of the heparin-induced Tau aggregation, 3) the similarities and differences between brain-derived and heparin-induced Tau fibrils; and 4) emerging concepts on the biochemical and structural determinants underpinning Tau pathological heterogeneity in Tauopathies. Our analyses identify specific knowledge gaps and call for 1) embracing the complexities of Tau pathologies; 2) reassessment of current approaches to investigate, model and reproduce pathological Tau aggregation as it occurs in the brain; 3) more research towards a better understanding of the naturally-occurring cofactor molecules that are associated with Tau brain pathology initiation and propagation; and 4) developing improved approaches for in vitro production of the Tau aggregates and fibrils that recapitulate and/or amplify the biochemical and structural complexity and diversity of pathological Tau in Tauopathies. This will result in better and more relevant tools, assays, and mechanistic models, which could significantly improve translational research and the development of drugs and antibodies that have higher chances for success in the clinic.
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Affiliation(s)
- Galina Limorenko
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Federal de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Federal de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
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Manzoor S, Gabr MT, Rasool B, Pal K, Hoda N. Dual targeting of acetylcholinesterase and tau aggregation: Design, synthesis and evaluation of multifunctional deoxyvasicinone analogues for Alzheimer's disease. Bioorg Chem 2021; 116:105354. [PMID: 34562674 DOI: 10.1016/j.bioorg.2021.105354] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 08/18/2021] [Accepted: 09/08/2021] [Indexed: 12/13/2022]
Abstract
Development of multitargeted ligands have demonstrated remarkable efficiency as potential therapeutics for Alzheimer's disease (AD). Herein, we reported a new series of deoxyvasicinone analogues as dual inhibitor of acetylcholinesterase (AChE) and tau aggregation that function as multitargeted ligands for AD. All the multitargeted ligands 11(a-j) and 15(a-g) were designed, synthesized, and validated by 1HNMR, 13CNMR and mass spectrometry. All the synthesized compounds 11(a-j) and 15(a-g) were screened for their ability to inhibit AChE, BACE1, amyloid fibrillation, α-syn aggregation, and tau aggregation. All the screened compounds possessed weak inhibition of BACE-1, Aβ42 and α-syn aggregation. However, several compounds were identified as potential hits in the AChE inhibitory screening assay and cellular tau aggregation screening. Among all compounds, 11f remarkably inhibited AChE activity and cellular tau oligomerization at single-dose screening (10 µM). Moreover, 11f displayed a half-maximal inhibitory concentration (IC50) value of 0.91 ± 0.05 µM and half-maximal effective concentration (EC50) value of 3.83 ± 0.51 µM for the inhibition of AChE and cellular tau oligomerization, respectively. In addition, the neuroprotective effect of 11f was determined in tau-expressing SH-SY5Y cells incubated with Aβ oligomers. These findings highlighted the potential of 11f to function as a multifunctional ligand for the development of promising anti-AD drugs.
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Affiliation(s)
- Shoaib Manzoor
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India.
| | - Moustafa T Gabr
- Department of Radiology, Stanford University, Stanford, CA 94305, United States.
| | - Bisma Rasool
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India
| | - Kavita Pal
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India
| | - Nasimul Hoda
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India.
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11
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Li Q, Xiong C, Liu H, Ge H, Yao X, Liu H. Computational Insights Into the Inhibition Mechanism of Proanthocyanidin B2 on Tau Hexapeptide (PHF6) Oligomer. Front Chem 2021; 9:666043. [PMID: 34336783 PMCID: PMC8316602 DOI: 10.3389/fchem.2021.666043] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/14/2021] [Indexed: 11/13/2022] Open
Abstract
The formation of amyloid fibrils from Tau is a key pathogenic feature of Alzheimer’s disease (AD). To disturb the formation of Tau aggregates is considered as a promising therapeutic strategy for AD. Recently, a natural product proanthocyanidin B2 (PB2) was confirmed to not only inhibit Tau aggregation, but also disaggregate Tau fibrils. Herein, to explore the inhibition mechanism of PB2 against Tau fibril and to provide the useful information for drug design and discovery, all-atom molecular dynamics simulations were carried out for the ordered Tau hexapeptide PHF6 oligomer in the presence and absence of PB2. The obtained result shows that PB2 can transform PHF6 oligomer from the ordered β-sheet structure into disordered one. Moreover, the clustering analysis and binding free energy calculations identify that S3 site is the most potential binding site. At S3 site, by hydrophobic and hydrogen bond interactions, the residues V309, Y310 and K311 are essential for binding with PB2, especially K311. In a word, our study reveals the molecular mechanism of PB2 inhibiting PHF6 aggregation and it will provide some valuable information for the development of Tau aggregation inhibitors.
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Affiliation(s)
- Qin Li
- School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Chunmei Xiong
- School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Hongli Liu
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Huizhen Ge
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou, China
| | - Xiaojun Yao
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou, China
| | - Huanxiang Liu
- School of Pharmacy, Lanzhou University, Lanzhou, China
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12
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Annadurai N, De Sanctis JB, Hajdúch M, Das V. Tau secretion and propagation: Perspectives for potential preventive interventions in Alzheimer's disease and other tauopathies. Exp Neurol 2021; 343:113756. [PMID: 33989658 DOI: 10.1016/j.expneurol.2021.113756] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/26/2021] [Accepted: 05/10/2021] [Indexed: 02/06/2023]
Abstract
Alzheimer's disease (AD) is characterised by the accumulation of intracytoplasmic aggregates of tau protein, which are suggested to spread in a prion-like manner between interconnected brain regions. This spreading is mediated by the secretion and uptake of tau from the extracellular space or direct cell-to-cell transmission through cellular protrusions. The prion-like tau then converts the endogenous, normal tau into pathological forms, resulting in neurodegeneration. The endoplasmic reticulum/Golgi-independent tau secretion through unconventional secretory pathways involves delivering misfolded and aggregated tau to the plasma membrane and its release into the extracellular space by non-vesicular and vesicular mechanisms. Although cytoplasmic tau was thought to be released only from degenerating cells, studies now show that cells constitutively secrete tau at low levels under physiological conditions. The mechanisms of secretion of tau under physiological and pathological conditions remain unclear. Therefore, a better understanding of these pathways is essential for developing therapeutic approaches that can target prion-like tau forms to prevent neurodegeneration progression in AD. This review focuses on unconventional secretion pathways involved in the spread of tau pathology in AD and presents these pathways as prospective areas for future AD drug discovery and development.
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Affiliation(s)
- Narendran Annadurai
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 5, 77900 Olomouc, Czech Republic
| | - Juan B De Sanctis
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 5, 77900 Olomouc, Czech Republic
| | - Marián Hajdúch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 5, 77900 Olomouc, Czech Republic
| | - Viswanath Das
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 5, 77900 Olomouc, Czech Republic.
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Malafaia D, Albuquerque HMT, Silva AMS. Amyloid-β and tau aggregation dual-inhibitors: A synthetic and structure-activity relationship focused review. Eur J Med Chem 2021; 214:113209. [PMID: 33548635 DOI: 10.1016/j.ejmech.2021.113209] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 11/16/2020] [Accepted: 01/12/2021] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) is one of the most common types of dementia, especially in elderly, with an increasing number of people suffering from this disease worldwide. There are no available disease-modifying therapies and only four drugs are approved for the relief of symptoms. Currently, the therapeutic approach used for AD treatment is based on single target drugs, which are not capable to stop its progression. To address this issue, multi-target compounds, combining two or more pharmacophores in a single molecular entity, have gained increasing interest to deal with the multiple factors related to AD. The exact cause of AD is not yet completely disclosed, and several hallmarks have been associated to this neurodegenerative disease. Even though, the accumulation of both amyloid-β plaques (Aβ) and neurofibrillary tangles (NFTs) are fully accepted as the main AD hallmarks, being object of lots of research for early-stage diagnosis and pharmacological therapy. In this context, this review summarizes the state-of-the-art in the field of dual-target inhibitors of both Aβ and tau aggregation simultaneously, including the design and synthetic strategy of the dual-target compounds, as well as a brief structure-activity relationships (SAR) analysis.
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Affiliation(s)
- Daniela Malafaia
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Hélio M T Albuquerque
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal.
| | - Artur M S Silva
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
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14
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Marreiro A, Van Kolen K, Sousa C, Temmerman L, Vasconcelos B, Crespo-Rodriguez R, van Weering JRT, Van Dam D, De Deyn PP, Apetri A, Schoofs L, Mercken MH. Comparison of size distribution and (Pro249-Ser258) epitope exposure in in vitro and in vivo derived Tau fibrils. BMC Mol Cell Biol 2020; 21:81. [PMID: 33183222 PMCID: PMC7661158 DOI: 10.1186/s12860-020-00320-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 10/20/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although several studies demonstrate prion-like properties of Tau fibrils, the effect of size in the seeding capacity of these aggregates is not fully understood. The aim of this study is to characterize Tau seeds by their size and seeding capacity. METHODS Tau aggregates were isolated from postmortem AD brain tissue and separated from low molecular weight species by sucrose gradient ultracentrifugation. Biochemical characterization of the different fractions was done by non-reducing Western blotting and aggregate-specific immuno-assays using in house developed anti-Tau monoclonal antibodies, including PT76 which binds to an epitope close to the microtubule-binding domain and, hence, also to K18. Seeding efficiency was then assessed in HEK293 cells expressing K18 FRET sensors. RESULTS We observed that upon sonication of Tau aggregates different size-distributed tau aggregates are obtained. In biochemical assays, these forms show higher signals than the non-sonicated material in some aggregation-specific Tau assays. This could be explained by an increased epitope exposure of the smaller aggregates created by the sonication. By analyzing human brain derived and recombinant (K18) Tau aggregates in a cellular FRET assay, it was observed that, in the absence of transfection reagent, sonicated aggregates showed higher aggregation induction. Preparations also showed altered profiles on native PAGE upon sonication and we could further separate different aggregate species based on their molecular weight via sucrose gradients. CONCLUSIONS This study further elucidates the molecular properties regarding relative aggregate size and seeding efficiency of sonicated vs. non-sonicated high molecular weight Tau species. This information will provide a better knowledge on how sonication, a commonly used technique in the field of study of Tau aggregation, impacts the aggregates. In addition, the description of PT76-based aggregation specific assay is a valuable tool to quantify K18 and human AD Tau fibrils.
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Affiliation(s)
- André Marreiro
- Neuroscience department, Janssen Pharmaceutical Companies of Johnson and Johnson, 2340, Beerse, Belgium.,Animal Physiology and Neurobiology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium
| | - Kristof Van Kolen
- Neuroscience department, Janssen Pharmaceutical Companies of Johnson and Johnson, 2340, Beerse, Belgium.
| | - Cristiano Sousa
- Neuroscience department, Janssen Pharmaceutical Companies of Johnson and Johnson, 2340, Beerse, Belgium
| | - Liesbet Temmerman
- Animal Physiology and Neurobiology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium
| | - Bruno Vasconcelos
- Neuroscience department, Janssen Pharmaceutical Companies of Johnson and Johnson, 2340, Beerse, Belgium
| | - Rosa Crespo-Rodriguez
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333, CN, Leiden, The Netherlands.,Neurochemistry Lab, Clinical Chemistry department of the Amsterdam UMC, Amsterdam, the Netherlands
| | - Jan R T van Weering
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam UMC, Amsterdam, the Netherlands
| | - Debby Van Dam
- Laboratory of Neurochemistry and Behavior, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.,Department of Neurology and Alzheimer Center Groningen, University Medical Center Groningen (UMCG), Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
| | - Peter P De Deyn
- Laboratory of Neurochemistry and Behavior, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.,Department of Neurology and Alzheimer Center Groningen, University Medical Center Groningen (UMCG), Hanzeplein 1, 9713, GZ, Groningen, The Netherlands.,Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA) Middelheim and Hoge Beuken, Lindendreef 1, 2020, Antwerp, Belgium.,Biobank, Institute Born-Bunge, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Adrian Apetri
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333, CN, Leiden, The Netherlands
| | - Liliane Schoofs
- Animal Physiology and Neurobiology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium
| | - Marc H Mercken
- Neuroscience department, Janssen Pharmaceutical Companies of Johnson and Johnson, 2340, Beerse, Belgium
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15
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Hu Y, Hu X, Lu Y, Shi S, Yang D, Yao T. New Strategy for Reducing Tau Aggregation Cytologically by A Hairpinlike Molecular Inhibitor, Tannic Acid Encapsulated in Liposome. ACS Chem Neurosci 2020; 11:3623-3634. [PMID: 33048528 DOI: 10.1021/acschemneuro.0c00508] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Inhibition of Tau protein aggregation is an attractive therapeutic target for Alzheimer's disease. However, most of the inhibitors have failed in clinical trials due to the superficial understanding of inhibition mechanism and drug-transfer pharmacokinetics. Innovation of design strategy has become a top priority. To afford a hairpinlike molecular inhibitor, we introduced tannic acid, a multibranched polyphenol molecule, and its moiety, gallic acid. We showed that tannic acid could effectively inhibit Tau aggregation through a multidentate chelation mode. We then encapsulated tannic acid in a non-neurotoxic liposome by lecithin/β-sitosterol, overcoating with Tween 80. Using transwell devices, we cytologically demonstrated that tannic acid liposome can successfully be transferred across the model of a blood-brain barrier made up of mouse brain microvascular endothelial cell bEnd.3 and effectively reduce Tau aggregation induced by fibrils of Tau peptide R3 in human neuroblastoma cell SK-N-SH. This result indicates the potential therapeutic effect of tannic acid liposome on Alzheimer's disease.
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Affiliation(s)
- Yuan Hu
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China
| | - Xiaochun Hu
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yonglin Lu
- School of Medicine, Tongji University, Shanghai 200092, China
| | - Shuo Shi
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China
| | - Danjing Yang
- School of Medicine, Tongji University, Shanghai 200092, China
| | - Tianming Yao
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China
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16
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Gabr M, Murugan NA. Discovery of biphenyl pyrazole scaffold for neurodegenerative diseases: A novel class of acetylcholinesterase-centered multitargeted ligands. Bioorg Med Chem Lett 2020; 30:127370. [PMID: 32738978 DOI: 10.1016/j.bmcl.2020.127370] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/23/2020] [Accepted: 06/25/2020] [Indexed: 12/19/2022]
Abstract
Multitargeted ligands have demonstrated remarkable efficiency as potential therapeutics for neurodegenerative diseases as they target multiple pathways involved in the progression of these diseases. Herein, we report first-in-class dual inhibitor of acetylcholinesterase (AChE) and tau aggregation as a novel class of multitargeted ligands for neurodegenerative diseases. The reported biphenyl pyrazole scaffold binds monomeric tau with submicromolar affinity and impedes the formation of tau oligomers at early stages. Additionally, the lead compound inhibited AChE activity with an IC50 value of 0.35 ± 0.02 μM. Remarkably, the neuroprotective effect of this lead in induced cytotoxicity model of SH-SY5Y neuroblastoma cells is superior to single-targeted AChE and tau-aggregation inhibitors. This scaffold would enable development of new generation of multitargeted ligands for neurodegenerative diseases that function through dual targeting of AChE and monomeric tau.
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Affiliation(s)
- Moustafa Gabr
- Department of Radiology, Stanford University School of Medicine, Stanford, CA 94305, United States.
| | - Natarajan Arul Murugan
- Department of Theoretical Chemistry and Biology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, S-106 91 Stockholm, Sweden
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17
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Garwain O, Yerramilli VS, Romero K, Scarlata S. The Gαq/phospholipase Cβ signaling system represses tau aggregation. Cell Signal 2020; 71:109620. [PMID: 32247043 PMCID: PMC7255494 DOI: 10.1016/j.cellsig.2020.109620] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 03/12/2020] [Accepted: 03/28/2020] [Indexed: 11/21/2022]
Abstract
Alzheimer's disease is typified by calcium dysfunction and neurofibrillary tangles of tau aggregates along with mitotic proteins. Using PC12 cells as a model system, we determined whether the Gαq/PLCβ/ calcium signaling pathway impacts the manifestation of Alzheimer's disease. Down-regulating PLCβ significantly increases tau protein expression and causes a large increase in tau aggregation. Stimulating Gαq to activate PLCβ results in a modest reduction in tau aggregation while inhibiting PLCβ activity results in a modest enhancement of tau aggregation. These results suggest that PLCβ may effect tau aggregation by an additional mechanism that is independent of its ability to transduce calcium signals. To this end, we found that a cytosolic population of PLCβ binds to a mitotic protein found in neurofibrillary tangles, CDK18, which promotes tau phosphorylation and aggregation. Taken together, our studies show that the loss of PLCβ1 can promote Alzheimer's disease by a combination of its catalytic activity and its interaction with mitotic proteins thus offering an orthogonal method to control tau aggregation.
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Affiliation(s)
- Osama Garwain
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, 100 Institute Rd., Worcester, MA 01609, USA
| | - V Siddartha Yerramilli
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, 100 Institute Rd., Worcester, MA 01609, USA
| | - Kate Romero
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, 100 Institute Rd., Worcester, MA 01609, USA
| | - Suzanne Scarlata
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, 100 Institute Rd., Worcester, MA 01609, USA.
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18
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Gorantla NV, Balaraman E, Chinnathambi S. Cobalt-based metal complexes prevent Repeat Tau aggregation and nontoxic to neuronal cells. Int J Biol Macromol 2020; 152:171-179. [PMID: 32105696 DOI: 10.1016/j.ijbiomac.2020.02.278] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 02/14/2020] [Accepted: 02/24/2020] [Indexed: 01/11/2023]
Abstract
Alzheimer's disease (AD) is a fatal neurodegenerative disorder with an alarming increase in the death rate every year. AD is characterised by an aberrant accumulation of proteins in the form of aggregates. The axonal microtubule-associated protein Tau and amyloid-β undergo structural transition to β-sheet rich structure and form aggregates in neuronal soma as well as in the extracellular region. The loss of Tau from microtubules leads to the disintegration of axon and causing neuronal degeneration. This led to the development of effective drugs against AD, to prevent Tau aggregation. Here, we synthesized and screen metal-based complexes to prevent Tau protein aggregation. ThS fluorescence and TEM suggested the role of synthetic cobalt complexes in inhibiting Tau aggregation. CD spectroscopy showed that these complexes prevented conformational changes in Tau to β-sheet. CBMCs were not toxic at lower concentrations and formed non-toxic Tau species. L1 and L2 prevented membrane leakage; whereas, higher concentrations of L3 caused membrane leakage as observed by LDH release assay. The overall results indicate the synthetic cobalt complexes to be a promising molecule against AD.
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Affiliation(s)
- Nalini V Gorantla
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India; Academy of Scientific and Innovative Research (AcSIR), 411008 Pune, India.
| | - Ekambaram Balaraman
- Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India; Academy of Scientific and Innovative Research (AcSIR), 411008 Pune, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India; Academy of Scientific and Innovative Research (AcSIR), 411008 Pune, India.
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Wichur T, Więckowska A, Więckowski K, Godyń J, Jończyk J, Valdivieso ÁDR, Panek D, Pasieka A, Sabaté R, Knez D, Gobec S, Malawska B. 1-Benzylpyrrolidine-3-amine-based BuChE inhibitors with anti-aggregating, antioxidant and metal-chelating properties as multifunctional agents against Alzheimer's disease. Eur J Med Chem 2019; 187:111916. [PMID: 31812794 DOI: 10.1016/j.ejmech.2019.111916] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/25/2019] [Accepted: 11/25/2019] [Indexed: 01/07/2023]
Abstract
Complex pathomechanism of Alzheimer's disease (AD) prompts researchers to develop multifunctional molecules in order to find effective therapy against AD. We designed and synthesized novel multifunctional ligands for which we assessed their activities towards butyrylcholinesterase, beta secretase, amyloid beta (Aβ) and tau protein aggregation as well as antioxidant and metal-chelating properties. All compounds showed dual anti-aggregating properties towards Aβ and tau protein in the in cellulo assay in Escherichia coli. Of particular interest are compounds 24b and 25b, which efficiently inhibit aggregation of Aβ and tau protein at 10 μM (24b: 45% for Aβ, 53% for tau; 25b: 49% for Aβ, 54% for tau). They display free radical scavenging capacity and antioxidant activity in ABTS and FRAP assays, respectively, and selectively chelate copper ions. Compounds 24b and 25b are also the most potent inhibitors of BuChE with IC50 of 2.39 μM and 1.94 μM, respectively. Promising in vitro activities of the presented multifunctional ligands as well as their original scaffold are a very interesting starting point for further research towards effective anti-AD treatment.
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Affiliation(s)
- Tomasz Wichur
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | - Anna Więckowska
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | - Krzysztof Więckowski
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | - Justyna Godyń
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | - Jakub Jończyk
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | | | - Dawid Panek
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | - Anna Pasieka
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland
| | - Raimon Sabaté
- Department of Pharmacy and Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Science, University of Barcelona, Av Joan XXIII 27-31, 08028, Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, Av Joan XXIII, S/N, 08028, Barcelona, Spain
| | - Damijan Knez
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva 7, 1000, Ljubljana, Slovenia
| | - Stanislav Gobec
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva 7, 1000, Ljubljana, Slovenia
| | - Barbara Malawska
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688, Kraków, Poland.
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Verstraelen P, Detrez JR, Verschuuren M, Kuijlaars J, Nuydens R, Timmermans JP, De Vos WH. Dysregulation of Microtubule Stability Impairs Morphofunctional Connectivity in Primary Neuronal Networks. Front Cell Neurosci 2017; 11:173. [PMID: 28690500 PMCID: PMC5480095 DOI: 10.3389/fncel.2017.00173] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 06/08/2017] [Indexed: 12/18/2022] Open
Abstract
Functionally related neurons assemble into connected networks that process and transmit electrochemical information. To do this in a coordinated manner, the number and strength of synaptic connections is tightly regulated. Synapse function relies on the microtubule (MT) cytoskeleton, the dynamics of which are in turn controlled by a plethora of MT-associated proteins, including the MT-stabilizing protein Tau. Although mutations in the Tau-encoding MAPT gene underlie a set of neurodegenerative disorders, termed tauopathies, the exact contribution of MT dynamics and the perturbation thereof to neuronal network connectivity has not yet been scrutinized. Therefore, we investigated the impact of targeted perturbations of MT stability on morphological (e.g., neurite- and synapse density) and functional (e.g., synchronous calcium bursting) correlates of connectivity in networks of primary hippocampal neurons. We found that treatment with MT-stabilizing or -destabilizing compounds impaired morphofunctional connectivity in a reversible manner. We also discovered that overexpression of MAPT induced significant connectivity defects, which were accompanied by alterations in MT dynamics and increased resistance to pharmacological MT depolymerization. Overexpression of a MAPT variant harboring the P301L point mutation in the MT-binding domain did far less, directly linking neuronal connectivity with Tau's MT binding affinity. Our results show that MT stability is a vulnerable node in tauopathies and that its precise pharmacological tuning may positively affect neuronal network connectivity. However, a critical balance in MT turnover causes it to be a difficult therapeutic target with a narrow operating window.
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Affiliation(s)
- Peter Verstraelen
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of AntwerpAntwerp, Belgium
| | - Jan R. Detrez
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of AntwerpAntwerp, Belgium
| | - Marlies Verschuuren
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of AntwerpAntwerp, Belgium
| | | | - Rony Nuydens
- Janssen Research and Development, Division of Janssen Pharmaceutica N.V.Beerse, Belgium
| | - Jean-Pierre Timmermans
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of AntwerpAntwerp, Belgium
| | - Winnok H. De Vos
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of AntwerpAntwerp, Belgium
- Department of Molecular Biotechnology, University of GhentGhent, Belgium
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Abstract
Alzheimer's disease (AD) is one of the neurodegenerative disease characterized by progressive neuronal loss in the brain. Its two major hallmarks are extracellular senile plaques and intracellular neurofibrillary tangles (NFTs), formed by aggregation of amyloid β-42 (Aβ-42) and Tau protein respectively. Aβ-42 is a transmembrane protein, which is produced after the sequential action of β- and γ-secretases, thus obtained peptide is released extracellularly and gets deposited on the neuron forming senile plaques. NFTs are composed of microtubule-associated protein-Tau (MAPT). Tau protein's major function is to stabilize the microtubule that provides a track on which the cargo proteins are shuttled and the stabilized microtubule also maintains shape and integrity of the neuronal cell. Tau protein is subjected to various modifications such as phosphorylation, ubiquitination, glycation, acetylation, truncation, glycosylation, deamination, and oxidation; these modifications ultimately lead to its aggregation. Phosphorylation is the major modification and is extensively studied with respect to Tau protein. Tau protein, however, undergoes certain level of phosphorylation and dephosphorylation, which regulates its affinity for microtubule and ultimately leading to microtubule assembly and disassembly. Our main aim was to study the native state of longest isoform of Tau (hTau40WT-4R2N) and its shortest isoform, (hTau23WT-3R0N), at various temperatures such as 10, 25, and 37 °C. Raman spectroscopic results suggested that the proportion of random coils or unordered structure depends on the temperature of the protein environment. Upon increase in the temperature from 10 to 37 °C, the proportion of random coils or unordered structures increased in the case of hTau40WT. However, we did not find a significant effect of temperature on the structure of hTau23WT. This current approach enables one to analyze the global conformation of soluble Tau in solution.
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Affiliation(s)
- Nalini Vijay Gorantla
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008, Pune, Maharashtra, India
- Academy of Scientific and Innovative Research (AcSIR), 10025, New Delhi, India
| | - Puneet Khandelwal
- Academy of Scientific and Innovative Research (AcSIR), 10025, New Delhi, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008 Pune, Maharashtra, India
| | - Pankaj Poddar
- Academy of Scientific and Innovative Research (AcSIR), 10025, New Delhi, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008 Pune, Maharashtra, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008, Pune, Maharashtra, India.
- Academy of Scientific and Innovative Research (AcSIR), 10025, New Delhi, India.
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22
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Abstract
A native conformation of a protein is essential for its biological role. In certain conditions, some proteins show non-native conformations, leading to aggregation, which in turn may produce severe pathologies. Such physiological conditions are classified as protein misfolding diseases. Alzheimer's disease (AD) is the most common form of dementia. Extracellular senile plaques formed by Amyloid β and intracellular aggregates formed by microtubule-associated protein Tau (MAPT) are the hallmarks of AD. Physiological role of MAPT is to maintain the integrity and stability of microtubules, however it tends to self-aggregate forming intracellular paired helical filaments (PHFs) during AD. MAPT is also subjected to various post-translational modifications such as phosphorylation, glycosylation, truncation, and acetylation. Being natively unfolded, MAPT is prone to full characterization at atomic level. Small-angle X-ray scattering (SAXS) is often applied in combination with other biophysical methods, like nuclear magnetic resonance (NMR), circular dichroism (CD), fluorescence spectroscopy, analytical ultracentrifugation (AUC), or dynamic light scattering (DLS) to characterize natively unfolded systems. Here we describe the practical aspects of MAPT characterization by SAXS and CD in detail as well as outline the inferred structural and functional implications.
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Affiliation(s)
- Nalini Vijay Gorantla
- Neurobiology Group, Division of Biochemical Sciences, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008, Pune, Maharashtra, India.,Academy of Scientific and Innovative Research (AcSIR), 10025, New Delhi, India
| | | | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008, Pune, Maharashtra, India. .,Academy of Scientific and Innovative Research (AcSIR), 10025, New Delhi, India.
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23
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Abstract
Abnormal tau aggregation is a pathological hallmark of neurodegenerative disease classified as tauopathy. Preventing tau aggregation becomes an important therapeutic strategy to cure tau-mediated neurodegeneration. Here, we describe a method to investigate intracellular tau aggregation by using a recently developed tau aggregation cell-based model named tau-BiFC. High-throughput and high-contents screening method for quantifying intracellular tau aggregation would expedite the discovery of drugs that inhibit tau aggregation.
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Affiliation(s)
- Sungsu Lim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea
| | - Dohee Kim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea
- Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, South Korea
| | - Dong Jin Kim
- Center for neuro-medicine, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 136-791, South Korea
| | - Yun Kyung Kim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea.
- Biological Chemistry, University of Science and Technology (UST), Daejeon, 305-333, South Korea.
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24
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Liu K, Liu Y, Li L, Qin P, Iqbal J, Deng Y, Qing H. Glycation alter the process of Tau phosphorylation to change Tau isoforms aggregation property. Biochim Biophys Acta Mol Basis Dis 2015; 1862:192-201. [PMID: 26655600 DOI: 10.1016/j.bbadis.2015.12.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 11/02/2015] [Accepted: 12/01/2015] [Indexed: 12/28/2022]
Abstract
The risk of tauopathies depends in part on the levels and modified composition of six Tau isoforms in the human brain. Abnormal phosphorylation of the Tau protein and the shift of the ratio of 3R Tau to 4R Tau are presumed to result in neurofibrillary pathology and neurodegeneration. Glycation has recently been linked to dementia and metabolic syndrome. To determine the contribution of Tau protein glycation and phosphorylation on Tau aggregation propensity, the assembled kinetics were examined in vitro using Thioflavin T fluorescence assays. We found that glycation and phosphorylation have different effects on aggregation propensity in different Tau isoforms. Different Tau proteins play important parts in each tauopathies, but 3R0N, fetal Tau protein, has no effect on tauopathies. Conversely, 4R2N has more modified sites and a higher tendency to aggregate, playing the most important role in 4R tauopathies. Finally, Glycation, which could modulate Tau phosphorylation, may occur before any other modification. It also regulates the 3R to 4R ratio and promotes 4R2N Tau protein aggregation. Decreasing the sites of glycation, as well as shifting other Tau proteins to 3R0N Tau proteins has potential therapeutic implications for tauopathies.
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Affiliation(s)
- Kefu Liu
- School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing 100081, PR China
| | - Yutong Liu
- Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing 100875, PR China
| | - Lingyun Li
- School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing 100081, PR China; School of Life Science, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China
| | - Peibin Qin
- Beijing Proteome Research Center, No.33, Life Science Park Road, Changping District, Beijing 102206, PR China
| | - Javed Iqbal
- School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing 100081, PR China
| | - Yulin Deng
- School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing 100081, PR China.
| | - Hong Qing
- School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing 100081, PR China.
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25
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Graham DL, Gray AJ, Joyce JA, Yu D, O'Moore J, Carlson GA, Shearman MS, Dellovade TL, Hering H. Increased O-GlcNAcylation reduces pathological tau without affecting its normal phosphorylation in a mouse model of tauopathy. Neuropharmacology 2014; 79:307-13. [PMID: 24326295 DOI: 10.1016/j.neuropharm.2013.11.025] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 10/21/2013] [Accepted: 11/29/2013] [Indexed: 01/14/2023]
Abstract
Neurofibrillary tangles (NFT), mainly consisting of fibrillar aggregates of hyperphosphorylated tau, are a defining pathological feature of Alzheimer's Disease and other tauopathies. Progressive accumulation of tau into NFT is considered to be a toxic cellular event causing neurodegeneration. Tau is subject to O-linked N-acetylglucosamine (O-GlcNAc) modification and O-GlcNAcylation of tau has been suggested to regulate tau phosphorylation. We tested if an increase in tau O-GlcNAcylation affected tau phosphorylation and aggregation in the rTg4510 tau transgenic mouse model. Acute treatment of rTg4510 mice with an O-GlcNAcase inhibitor transiently reduced tau phosphorylation at epitopes implicated in tau pathology. More importantly, long-term inhibitor treatment strongly increased tau O-GlcNAcylation, reduced the number of dystrophic neurons, and protected against the formation of pathological tau species without altering the phosphorylation of non-pathological tau. This indicates that O-GlcNAcylation prevents the aggregation of tau in a manner that does not affect its normal phosphorylation state. Collectively, our results support O-GlcNAcase inhibition as a potential therapeutic strategy for the treatment of Alzheimer's Disease and other tauopathies.
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