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Kanaan NM. Tau here, tau there, tau almost everywhere: Clarifying the distribution of tau in the adult CNS. Cytoskeleton (Hoboken) 2024; 81:107-115. [PMID: 38102924 PMCID: PMC10851165 DOI: 10.1002/cm.21820] [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: 08/25/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/17/2023]
Abstract
The microtubule-associated protein tau has gained significant attention over the last several decades primarily due to its apparent role in the pathogenesis of several diseases, most notably Alzheimer's disease. While the field has focused largely on tau's potential contributions to disease mechanisms, comparably less work has focused on normal tau physiology. Moreover, as the field has grown, some misconceptions and dogmas regarding normal tau physiology have become engrained in the traditional narrative. Here, one of the most common misconceptions regarding tau, namely its normal cellular/subcellular distribution in the CNS, is discussed. The literature describing the presence of tau in neuronal somata, dendrites, axons and synapses, as well as in glial cells is described. The origins for the erroneous description of tau as an "axon-specific," "axon-enriched" and/or "neuron-specific" protein are discussed as well. The goal of this work is to help address these specific dogmatic misconceptions and provide a concise description of tau's normal cellular/subcellular localization in the adult CNS. This information can help refine our collective understanding of- and hypotheses about tau biology and pathobiology.
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Affiliation(s)
- Nicholas M. Kanaan
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA
- Neuroscience Program, Michigan State University, East Lansing, Michigan, USA
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Ori-McKenney KM, McKenney RJ. Tau oligomerization on microtubules in health and disease. Cytoskeleton (Hoboken) 2024; 81:35-40. [PMID: 37747123 PMCID: PMC10841430 DOI: 10.1002/cm.21785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/22/2023] [Accepted: 08/23/2023] [Indexed: 09/26/2023]
Affiliation(s)
- Kassandra M Ori-McKenney
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, California, USA
| | - Richard J McKenney
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, California, USA
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3
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Tseng JH, Cohen TJ. The emerging nontraditional roles for tau in the brain. Cytoskeleton (Hoboken) 2024; 81:89-94. [PMID: 38063261 PMCID: PMC11068308 DOI: 10.1002/cm.21811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/02/2023] [Accepted: 11/15/2023] [Indexed: 01/24/2024]
Affiliation(s)
- Jui-Heng Tseng
- Arizona State University-Banner Neurodegenerative Disease Research Center at the Biodesign Institute, Tempe, AZ 85287, USA
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Todd J. Cohen
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
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4
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Shen Z, Sun D, Savastano A, Varga SJ, Cima-Omori MS, Becker S, Honigmann A, Zweckstetter M. Multivalent Tau/PSD-95 interactions arrest in vitro condensates and clusters mimicking the postsynaptic density. Nat Commun 2023; 14:6839. [PMID: 37891164 PMCID: PMC10611757 DOI: 10.1038/s41467-023-42295-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
Alzheimer's disease begins with mild memory loss and slowly destroys memory and thinking. Cognitive impairment in Alzheimer's disease has been associated with the localization of the microtubule-associated protein Tau at the postsynapse. However, the correlation between Tau at the postsynapse and synaptic dysfunction remains unclear. Here, we show that Tau arrests liquid-like droplets formed by the four postsynaptic density proteins PSD-95, GKAP, Shank, Homer in solution, as well as NMDA (N-methyl-D-aspartate)-receptor-associated protein clusters on synthetic membranes. Tau-mediated condensate/cluster arrest critically depends on the binding of multiple interaction motifs of Tau to a canonical GMP-binding pocket in the guanylate kinase domain of PSD-95. We further reveal that competitive binding of a high-affinity phosphorylated peptide to PSD-95 rescues the diffusional dynamics of an NMDA truncated construct, which contains the last five amino acids of the NMDA receptor subunit NR2B fused to the C-terminus of the tetrameric GCN4 coiled-coil domain, in postsynaptic density-like condensates/clusters. Taken together, our findings propose a molecular mechanism where Tau modulates the dynamic properties of the postsynaptic density.
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Affiliation(s)
- Zheng Shen
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Daxiao Sun
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Adriana Savastano
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Sára Joana Varga
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Maria-Sol Cima-Omori
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Stefan Becker
- Max Planck Institute for Multidisciplinary Sciences, Department of NMR-based Structural Biology, Am Fassberg 11, 37077, Göttingen, Germany
| | - Alf Honigmann
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Technische Universität Dresden, Biotechnologisches Zentrum (BIOTEC), Dresden, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany.
- Max Planck Institute for Multidisciplinary Sciences, Department of NMR-based Structural Biology, Am Fassberg 11, 37077, Göttingen, Germany.
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Benskey MJ, Panoushek S, Saito T, Saido TC, Grabinski T, Kanaan NM. Behavioral and neuropathological characterization over the adult lifespan of the human tau knock-in mouse. Front Aging Neurosci 2023; 15:1265151. [PMID: 37842124 PMCID: PMC10576558 DOI: 10.3389/fnagi.2023.1265151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 09/11/2023] [Indexed: 10/17/2023] Open
Abstract
Tau is a microtubule-associated protein with a diverse functional repertoire linked to neurodegenerative disease. Recently, a human tau knock-in (MAPT KI) mouse was developed that may overcome many limitations associated with current animal models used to study tau. In MAPT KI mice, the entire murine Mapt gene was replaced with the human MAPT gene under control of the endogenous Mapt promoter. This model represents an ideal in vivo platform to study the function and dysfunction of human tau protein. Accordingly, a detailed understanding of the effects MAPT KI has on structure and function of the CNS is warranted. Here, we provide a detailed behavioral and neuropathological assessment of MAPT KI mice. We compared MAPT KI to wild-type (WT) C57BL/6j mice in behavioral assessments of anxiety, attention, working memory, spatial memory, and motor performance from 6 to 24 months (m) of age. Using immunohistological and biochemical assays, we quantified markers of glia (microglia, astrocytes and oligodendrocytes), synaptic integrity, neuronal integrity and the cytoskeleton. Finally, we quantified levels of total tau, tau isoforms, tau phosphorylation, and tau conformations. MAPT KI mice show normal cognitive and locomotor behavior at all ages, and resilience to mild age-associated locomotor deficits observed in WT mice. Markers of neuronal and synaptic integrity are unchanged in MAPT KI mice with advancing age. Glial markers are largely unchanged in MAPT KI mice, but glial fibrillary acidic protein is increased in the hippocampus of WT and MAPT KI mice at 24 m. MAPT KI mice express all 6 human tau isoforms and levels of tau remain stable throughout adulthood. Hippocampal tau in MAPT KI and WT mice is phosphorylated at serine 396/404 (PHF1) and murine tau in WT animals displays more PHF1 phosphorylation at 6 and 12 m. Lastly, we extended previous reports showing that MAPT KI mice do not display overt pathology. No evidence of other tau phosphorylation residues (AT8, pS422) or abnormal conformations (TNT2 or TOC1) associated with pathogenic tau were detected. The lack of overt pathological changes in MAPT KI mice make this an ideal platform for future investigations into the function and dysfunction of tau protein in vivo.
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Affiliation(s)
- Matthew J. Benskey
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Spencer Panoushek
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
- Laboratory for Proteolytic Neuroscience, Riken Center for Brain Science, Wako, Japan
| | - Takaomi C. Saido
- Laboratory for Proteolytic Neuroscience, Riken Center for Brain Science, Wako, Japan
| | - Tessa Grabinski
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Nicholas M. Kanaan
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
- Neuroscience Program, Michigan State University, East Lansing, MI, United States
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Daniilidou M, Eroli F, Alanko V, Goikolea J, Latorre-Leal M, Rodriguez-Rodriguez P, Griffiths WJ, Wang Y, Pacciarini M, Brinkmalm A, Zetterberg H, Blennow K, Rosenberg A, Bogdanovic N, Winblad B, Kivipelto M, Ibghi D, Cedazo-Minguez A, Maioli S, Matton A. Alzheimer's disease biomarker profiling in a memory clinic cohort without common comorbidities. Brain Commun 2023; 5:fcad228. [PMID: 37680670 PMCID: PMC10481253 DOI: 10.1093/braincomms/fcad228] [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: 12/21/2022] [Revised: 05/17/2023] [Accepted: 08/24/2023] [Indexed: 09/09/2023] Open
Abstract
Alzheimer's disease is a multifactorial disorder with large heterogeneity. Comorbidities such as hypertension, hypercholesterolaemia and diabetes are known contributors to disease progression. However, less is known about their mechanistic contribution to Alzheimer's pathology and neurodegeneration. The aim of this study was to investigate the relationship of several biomarkers related to risk mechanisms in Alzheimer's disease with the well-established Alzheimer's disease markers in a memory clinic population without common comorbidities. We investigated 13 molecular markers representing key mechanisms underlying Alzheimer's disease pathogenesis in CSF from memory clinic patients without diagnosed hypertension, hypercholesterolaemia or diabetes nor other neurodegenerative disorders. An analysis of covariance was used to compare biomarker levels between clinical groups. Associations were analysed by linear regression. Two-step cluster analysis was used to determine patient clusters. Two key markers were analysed by immunofluorescence staining in the hippocampus of non-demented control and Alzheimer's disease individuals. CSF samples from a total of 90 participants were included in this study: 30 from patients with subjective cognitive decline (age 62.4 ± 4.38, female 60%), 30 with mild cognitive impairment (age 65.6 ± 7.48, female 50%) and 30 with Alzheimer's disease (age 68.2 ± 7.86, female 50%). Angiotensinogen, thioredoxin-1 and interleukin-15 had the most prominent associations with Alzheimer's disease pathology, synaptic and axonal damage markers. Synaptosomal-associated protein 25 kDa and neurofilament light chain were increased in mild cognitive impairment and Alzheimer's disease patients. Grouping biomarkers by biological function showed that inflammatory and survival components were associated with Alzheimer's disease pathology, synaptic dysfunction and axonal damage. Moreover, a vascular/metabolic component was associated with synaptic dysfunction. In the data-driven analysis, two patient clusters were identified: Cluster 1 had increased CSF markers of oxidative stress, vascular pathology and neuroinflammation and was characterized by elevated synaptic and axonal damage, compared with Cluster 2. Clinical groups were evenly distributed between the clusters. An analysis of post-mortem hippocampal tissue showed that compared with non-demented controls, angiotensinogen staining was higher in Alzheimer's disease and co-localized with phosphorylated-tau. The identification of biomarker-driven endophenotypes in cognitive disorder patients further highlights the biological heterogeneity of Alzheimer's disease and the importance of tailored prevention and treatment strategies.
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Affiliation(s)
- Makrina Daniilidou
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
- Division of Clinical Geriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 141 83 Huddinge, Sweden
| | - Francesca Eroli
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
| | - Vilma Alanko
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
- Division of Clinical Geriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 141 83 Huddinge, Sweden
| | - Julen Goikolea
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
| | - Maria Latorre-Leal
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
| | - Patricia Rodriguez-Rodriguez
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
| | | | - Yuqin Wang
- Swansea University Medical School, Swansea SA2 8PP, UK
| | | | - Ann Brinkmalm
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 413 90 Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 413 90 Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 413 90 Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 413 90 Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1N3AR, UK
- UK Dementia Research Institute at UCL, London WC1N3AR, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 413 90 Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 413 90 Mölndal, Sweden
| | - Anna Rosenberg
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, FI-70029 Kuopio, Finland
| | - Nenad Bogdanovic
- Theme Inflammation and Aging, Karolinska University Hospital, 141 83 Huddinge, Sweden
| | - Bengt Winblad
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
- Theme Inflammation and Aging, Karolinska University Hospital, 141 83 Huddinge, Sweden
| | - Miia Kivipelto
- Division of Clinical Geriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 141 83 Huddinge, Sweden
- Theme Inflammation and Aging, Karolinska University Hospital, 141 83 Huddinge, Sweden
- Ageing Epidemiology Research Unit, School of Public Health, Imperial College London, London SW7 2AZ, UK
| | - Delphine Ibghi
- Neurodegeneration Cluster, Rare and Neurologic Disease Research Sanofi R&D, F-91380 Chilly-Mazarin, France
| | - Angel Cedazo-Minguez
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
- Neurodegeneration Cluster, Rare and Neurologic Disease Research Sanofi R&D, F-91380 Chilly-Mazarin, France
| | - Silvia Maioli
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
| | - Anna Matton
- Division of Neurogeriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 171 64 Solna, Sweden
- Division of Clinical Geriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 141 83 Huddinge, Sweden
- Ageing Epidemiology Research Unit, School of Public Health, Imperial College London, London SW7 2AZ, UK
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Gambardella JC, Schoephoerster W, Bondarenko V, Yandell BS, Emborg ME. Expression of tau and phosphorylated tau in the brain of normal and hemiparkinsonian rhesus macaques. J Comp Neurol 2023; 531:1198-1216. [PMID: 37098996 PMCID: PMC10247506 DOI: 10.1002/cne.25490] [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: 11/19/2022] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/27/2023]
Abstract
Tau is a neuronal protein involved in microtubule stabilization and intracellular vesicle transport in axons. In neurodegenerative disorders termed "tauopathies," like Alzheimer's and Parkinson's disease, tau becomes hyperphosphorylated and forms intracellular inclusions. Rhesus macaques are widely used for studying ageing processes and modeling neurodegenerative disorders, yet little is known about endogenous tau expression in their brains. In this study, immunohistochemical methods were used to map and characterize total tau, 3R- and 4R-tau isoforms, and phosphorylated tau (pThr231-tau and pSer202/Thr205-tau/AT8) expression bilaterally in 16 brain regions of normal and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced hemiparkinsonian adult rhesus macaques. Tau-immunoreactivity (-ir), including both 3R and 4R isoforms, was observed throughout the brain, with varying regional intensities. The anterior cingulate cortex, entorhinal cortex, and hippocampus displayed the most robust tau-ir, while the subthalamic nucleus and white matter regions had minimal expression. Tau was present in neurons of gray matter regions; it was preferentially observed in fibers of the globus pallidus and substantia nigra and in cell bodies of the thalamus and subthalamic nucleus. In white matter regions, tau was abundantly present in oligodendrocytes. Additionally, neuronal pThr231-tau-ir was abundant in all brain regions, but not AT8-ir. Differences in regional and intracellular protein expression were not detected between control subjects and both brain hemispheres of MPTP-treated animals. Specifically, tau-ir in the substantia nigra of all subjects colocalized with GABAergic neurons. Overall, this report provides an in-depth characterization of tau expression in the rhesus macaque brain to facilitate future investigations for understanding and modeling tau pathology in this species.
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Affiliation(s)
- Julia C. Gambardella
- Preclinical Parkinson’s Research Program, Wisconsin National Primate Research Center, University of Wisconsin-Madison
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison
| | - Wyatt Schoephoerster
- Preclinical Parkinson’s Research Program, Wisconsin National Primate Research Center, University of Wisconsin-Madison
| | - Viktoriya Bondarenko
- Preclinical Parkinson’s Research Program, Wisconsin National Primate Research Center, University of Wisconsin-Madison
| | | | - Marina E. Emborg
- Preclinical Parkinson’s Research Program, Wisconsin National Primate Research Center, University of Wisconsin-Madison
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison
- Department of Medical Physics, University of Wisconsin-Madison
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Acero VP, Das S, Rivellini O, Purvis EM, Adewole DO, Cullen DK. Emergent structural and functional properties of hippocampal multi-cellular aggregates. Front Neurosci 2023; 17:1171115. [PMID: 37397454 PMCID: PMC10311220 DOI: 10.3389/fnins.2023.1171115] [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: 02/21/2023] [Accepted: 05/24/2023] [Indexed: 07/04/2023] Open
Abstract
Hippocampal neural networks are distinctly capable of integrating multi-modal sensory inputs to drive memory formation. Neuroscientific investigations using simplified in vitro models have greatly relied on planar (2D) neuronal cultures made from dissociated tissue. While these models have served as simple, cost-effective, and high-throughput tools for examining various morphological and electrophysiological characteristics of hippocampal networks, 2D cultures fail to reconstitute critical elements of the brain microenvironment that may be necessary for the emergence of sophisticated integrative network properties. To address this, we utilized a forced aggregation technique to generate high-density (>100,000 cells/mm3) multi-cellular three-dimensional aggregates using rodent embryonic hippocampal tissue. We contrasted the emergent structural and functional properties of aggregated (3D) and dissociated (2D) cultures over 28 days in vitro (DIV). Hippocampal aggregates displayed robust axonal fasciculation across large distances and significant neuronal polarization, i.e., spatial segregation of dendrites and axons, at earlier time points compared to dissociated cultures. Moreover, we found that astrocytes in aggregate cultures self-organized into non-overlapping quasi-domains and developed highly stellate morphologies resembling astrocyte structures in vivo. We maintained cultures on multi-electrode arrays (MEAs) to assess spontaneous electrophysiological activity for up to 28 DIV. We found that 3D networks of aggregated cultures developed highly synchronized networks and with high burstiness by 28 DIV. We also demonstrated that dual-aggregate networks became active by 7 DIV, in contrast to single-aggregate networks which became active and developed synchronous bursting activity with repeating motifs by 14 DIV. Taken together, our findings demonstrate that the high-density, multi-cellular, 3D microenvironment of hippocampal aggregates supports the recapitulation of emergent biofidelic morphological and functional properties. Our findings suggest that neural aggregates may be used as segregated, modular building blocks for the development of complex, multi-nodal neural network topologies.
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Affiliation(s)
- Victor P. Acero
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Suradip Das
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Olivia Rivellini
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Erin M. Purvis
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Dayo O. Adewole
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Daniel Kacy Cullen
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Chapelet G, Béguin N, Castellano B, Grit I, de Coppet P, Oullier T, Neunlist M, Blottière H, Rolli-Derkinderen M, Le Dréan G, Derkinderen P. Tau expression and phosphorylation in enteroendocrine cells. Front Neurosci 2023; 17:1166848. [PMID: 37332860 PMCID: PMC10272410 DOI: 10.3389/fnins.2023.1166848] [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: 02/15/2023] [Accepted: 05/17/2023] [Indexed: 06/20/2023] Open
Abstract
Background and objective There is mounting evidence to suggest that the gut-brain axis is involved in the development of Parkinson's disease (PD). In this regard, the enteroendocrine cells (EEC), which faces the gut lumen and are connected with both enteric neurons and glial cells have received growing attention. The recent observation showing that these cells express alpha-synuclein, a presynaptic neuronal protein genetically and neuropathologically linked to PD came to reinforce the assumption that EEC might be a key component of the neural circuit between the gut lumen and the brain for the bottom-up propagation of PD pathology. Besides alpha-synuclein, tau is another key protein involved in neurodegeneration and converging evidences indicate that there is an interplay between these two proteins at both molecular and pathological levels. There are no existing studies on tau in EEC and therefore we set out to examine the isoform profile and phosphorylation state of tau in these cells. Methods Surgical specimens of human colon from control subjects were analyzed by immunohistochemistry using a panel of anti-tau antibodies together with chromogranin A and Glucagon-like peptide-1 (two EEC markers) antibodies. To investigate tau expression further, two EEC lines, namely GLUTag and NCI-H716 were analyzed by Western blot with pan-tau and tau isoform specific antibodies and by RT-PCR. Lambda phosphatase treatment was used to study tau phosphorylation in both cell lines. Eventually, GLUTag were treated with propionate and butyrate, two short chain fatty acids known to sense EEC, and analyzed at different time points by Western blot with an antibody specific for tau phosphorylated at Thr205. Results We found that tau is expressed and phosphorylated in EEC in adult human colon and that both EEC lines mainly express two tau isoforms that are phosphorylated under basal condition. Both propionate and butyrate regulated tau phosphorylation state by decreasing its phosphorylation at Thr205. Conclusion and inference Our study is the first to characterize tau in human EEC and in EEC lines. As a whole, our findings provide a basis to unravel the functions of tau in EEC and to further investigate the possibility of pathological changes in tauopathies and synucleinopathies.
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Affiliation(s)
- Guillaume Chapelet
- Nantes Université, INSERM, CHU Nantes, The Enteric Nervous System in Gut and Brain Disorders, Nantes, France
| | - Nora Béguin
- Nantes Université, INSERM, CHU Nantes, The Enteric Nervous System in Gut and Brain Disorders, Nantes, France
| | | | - Isabelle Grit
- Nantes Université, INRAE, IMAD, CRNH-O, UMR 1280, PhAN, Nantes, France
| | - Pierre de Coppet
- Nantes Université, INRAE, IMAD, CRNH-O, UMR 1280, PhAN, Nantes, France
| | - Thibauld Oullier
- Nantes Université, INSERM, CHU Nantes, The Enteric Nervous System in Gut and Brain Disorders, Nantes, France
| | - Michel Neunlist
- Nantes Université, INSERM, CHU Nantes, The Enteric Nervous System in Gut and Brain Disorders, Nantes, France
| | - Hervé Blottière
- Nantes Université, INRAE, IMAD, CRNH-O, UMR 1280, PhAN, Nantes, France
| | - Malvyne Rolli-Derkinderen
- Nantes Université, INSERM, CHU Nantes, The Enteric Nervous System in Gut and Brain Disorders, Nantes, France
| | - Gwenola Le Dréan
- Nantes Université, INRAE, IMAD, CRNH-O, UMR 1280, PhAN, Nantes, France
| | - Pascal Derkinderen
- Nantes Université, INSERM, CHU Nantes, The Enteric Nervous System in Gut and Brain Disorders, Nantes, France
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10
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Torii T, Miyamoto Y, Nakata R, Higashi Y, Shinmyo Y, Kawasaki H, Miyasaka T, Misonou H. Identification of Tau protein as a novel marker for maturation and pathological changes of oligodendrocytes. Glia 2023; 71:1002-1017. [PMID: 36565228 DOI: 10.1002/glia.24322] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 12/04/2022] [Accepted: 12/06/2022] [Indexed: 12/25/2022]
Abstract
Microtubule-associated protein Tau is primarily expressed in axons of neurons, but also in Olig2-positive oligodendrocytes in adult rodent and monkey brains. In this study, we sought to determine at what cell stage Tau becomes expressed in the oligodendrocyte lineage. We performed immunostaining of adult mouse brain sections using well-known markers of oligodendrocyte lineage and found that Tau is expressed in mature oligodendrocytes, but not in oligodendrocyte progenitors and immature pre-oligodendrocytes. We also investigated Tau expression in developing mouse brain. Surprisingly, Tau expression occurred after the peak of myelination and even exceeded GSTπ expression, which has been considered as a marker of myelinating oligodendrocytes. These results suggest Tau as a novel marker of oligodendrocyte maturation. We then investigated whether Tau is important for oligodendrocyte development and/or myelination and how Tau changes in demyelination. First, we found no changes in myelination and oligodendrocyte markers in Tau knockout mice, suggesting that Tau is dispensable. Next, we analyzed the proteolipid protein 1 transgenic model of Pelizaeus-Merzbacher disease, which is a rare leukodystrophy. In hemizygous transgenic mice, the number of Tau-positive cells were significantly increased as compared with wild type mice. These cells were also positive for Olig2, CC1, and GSTπ, but not PDGFRα and GPR17. In stark contrast, the expression level of Tau, as well as GSTπ, was dramatically decreased in the cuprizone-induced model of multiple sclerosis. Taken together, we propose Tau as a new marker of oligodendrocyte lineage and for investigating demyelination lesions.
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Affiliation(s)
- Tomohiro Torii
- Laboratory of Ion Channel Pathophysiology, Graduate School of Brain Science, Doshisha University, Kyotanabe-shi, Kyoto, Japan.,Center for Research in Neurodegenerative Diseases, Doshisha University, Kyotanabe-shi, Kyoto, Japan
| | - Yuki Miyamoto
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagayaku, Tokyo, Japan
| | - Rinaho Nakata
- Laboratory of Ion Channel Pathophysiology, Graduate School of Brain Science, Doshisha University, Kyotanabe-shi, Kyoto, Japan
| | - Yuto Higashi
- Department of Neuropathology, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe-shi, Kyoto, Japan
| | - Yohei Shinmyo
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa-shi, Ishikawa, Japan
| | - Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa-shi, Ishikawa, Japan
| | - Tomohiro Miyasaka
- Center for Research in Neurodegenerative Diseases, Doshisha University, Kyotanabe-shi, Kyoto, Japan.,Department of Neuropathology, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe-shi, Kyoto, Japan
| | - Hiroaki Misonou
- Laboratory of Ion Channel Pathophysiology, Graduate School of Brain Science, Doshisha University, Kyotanabe-shi, Kyoto, Japan.,Center for Research in Neurodegenerative Diseases, Doshisha University, Kyotanabe-shi, Kyoto, Japan
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11
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Jimenez-Harrison D, Huseby CJ, Hoffman CN, Sher S, Snyder D, Seal B, Yuan C, Fu H, Wysocki V, Giorgini F, Kuret J. DJ-1 Molecular Chaperone Activity Depresses Tau Aggregation Propensity through Interaction with Monomers. Biochemistry 2023; 62:976-988. [PMID: 36813261 PMCID: PMC9997487 DOI: 10.1021/acs.biochem.2c00581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/19/2023] [Indexed: 02/24/2023]
Abstract
Tau aggregate-bearing lesions are pathological markers and potential mediators of tauopathic neurodegenerative diseases, including Alzheimer's disease. The molecular chaperone DJ-1 colocalizes with tau pathology in these disorders, but it has been unclear what functional link exists between them. In this study, we examined the consequences of tau/DJ-1 interaction as isolated proteins in vitro. When added to full-length 2N4R tau under aggregation-promoting conditions, DJ-1 inhibited both the rate and extent of filament formation in a concentration-dependent manner. Inhibitory activity was low affinity, did not require ATP, and was not affected by substituting oxidation incompetent missense mutation C106A for wild-type DJ-1. In contrast, missense mutations previously linked to familial Parkinson's disease and loss of α-synuclein chaperone activity, M26I and E64D, displayed diminished tau chaperone activity relative to wild-type DJ-1. Although DJ-1 directly bound the isolated microtubule-binding repeat region of tau protein, exposure of preformed tau seeds to DJ-1 did not diminish seeding activity in a biosensor cell model. These data reveal DJ-1 to be a holdase chaperone capable of engaging tau as a client in addition to α-synuclein. Our findings support a role for DJ-1 as part of an endogenous defense against the aggregation of these intrinsically disordered proteins.
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Affiliation(s)
- Daniela Jimenez-Harrison
- Medical
Scientist Training Program, The Ohio State
University, Columbus, Ohio 43210, United States
| | - Carol J. Huseby
- Department
of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, Ohio 43210, United States
| | - Claire N. Hoffman
- Department
of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, Ohio 43210, United States
| | - Steven Sher
- Medical
Scientist Training Program, The Ohio State
University, Columbus, Ohio 43210, United States
| | - Dalton Snyder
- Department
of Chemistry and Biochemistry, The Ohio
State University College of Medicine, Columbus, Ohio 43210, United States
| | - Brayden Seal
- Department
of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, Ohio 43210, United States
| | - Chunhua Yuan
- Campus
Chemical Instrument Center, The Ohio State
University College of Medicine, Columbus, Ohio 43210, United States
| | - Hongjun Fu
- Department
of Neuroscience, The Ohio State University
College of Medicine, Columbus, Ohio 43210, United States
| | - Vicki Wysocki
- Department
of Chemistry and Biochemistry, The Ohio
State University College of Medicine, Columbus, Ohio 43210, United States
| | - Flaviano Giorgini
- Department
of Genetics and Genome Biology, University
of Leicester, Leicester LE1 7RH, United
Kingdom
| | - Jeff Kuret
- Department
of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, Ohio 43210, United States
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12
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Oligodendrocytes Prune Axons Containing α-Synuclein Aggregates In Vivo: Lewy Neurites as Precursors of Glial Cytoplasmic Inclusions in Multiple System Atrophy? Biomolecules 2023; 13:biom13020269. [PMID: 36830639 PMCID: PMC9953613 DOI: 10.3390/biom13020269] [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: 12/12/2022] [Revised: 01/17/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023] Open
Abstract
α-Synucleinopathies are spreading neurodegenerative disorders characterized by the intracellular accumulation of insoluble aggregates populated by α-Synuclein (α-Syn) fibrils. In Parkinson's disease (PD) and dementia with Lewy bodies, intraneuronal α-Syn aggregates are referred to as Lewy bodies in the somata and as Lewy neurites in the neuronal processes. In multiple system atrophy (MSA) α-Syn aggregates are also found within mature oligodendrocytes (OLs) where they form Glial Cytoplasmic Inclusions (GCIs). However, the origin of GCIs remains enigmatic: (i) mature OLs do not express α-Syn, precluding the seeding and the buildup of inclusions and (ii) the artificial overexpression of α-Syn in OLs of transgenic mice results in a burden of soluble phosphorylated α-Syn but fails to form α-Syn fibrils. In contrast, mass spectrometry of α-Syn fibrillar aggregates from MSA patients points to the neuronal origin of the proteins intimately associated with the fibrils within the GCIs. This suggests that GCIs are preassembled in neurons and only secondarily incorporated into OLs. Interestingly, we recently isolated a synthetic human α-Syn fibril strain (1B fibrils) capable of seeding a type of neuronal inclusion observed early and specifically during MSA. Our goal was thus to investigate whether the neuronal α-Syn pathology seeded by 1B fibrils could eventually be transmitted to OLs to form GCIs in vivo. After confirming that mature OLs did not express α-Syn to detectable levels in the adult mouse brain, a series of mice received unilateral intra-striatal injections of 1B fibrils. The resulting α-Syn pathology was visualized using phospho-S129 α-Syn immunoreactivity (pSyn). We found that even though 1B fibrils were injected unilaterally, many pSyn-positive neuronal somas were present in layer V of the contralateral perirhinal cortex after 6 weeks. This suggested a fast retrograde spread of the pathology along the axons of crossing cortico-striatal neurons. We thus scrutinized the posterior limb of the anterior commissure, i.e., the myelinated interhemispheric tract containing the axons of these neurons: we indeed observed numerous pSyn-positive linear Lewy Neurites oriented parallel to the commissural axis, corresponding to axonal segments filled with aggregated α-Syn, with no obvious signs of OL α-Syn pathology at this stage. After 6 months however, the commissural Lewy neurites were no longer parallel but fragmented, curled up, sometimes squeezed in-between two consecutive OLs in interfascicular strands, or even engulfed inside OL perikarya, thus forming GCIs. We conclude that the 1B fibril strain can rapidly induce an α-Syn pathology typical of MSA in mice, in which the appearance of GCIs results from the pruning of diseased axonal segments containing aggregated α-Syn.
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13
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Karimi N, Bayram Çatak F, Arslan E, Saghazadeh A, Rezaei N. Tau immunotherapy in Alzheimer’s disease and progressive supranuclear palsy. Int Immunopharmacol 2022; 113:109445. [DOI: 10.1016/j.intimp.2022.109445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 11/06/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
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14
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Torii T, Miyasaka T, Misonou H. The organization of microtubules and Tau in oligodendrocytes: Tau pathology in damaged oligodendrocytes. Front Cell Dev Biol 2022; 10:950682. [PMID: 36274848 PMCID: PMC9579343 DOI: 10.3389/fcell.2022.950682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/05/2022] [Indexed: 11/13/2022] Open
Abstract
Tau is abundantly expressed in neurons, however previous reports and our recent study showed tau also exist in oligodendrocytes. Also the expression levels of tau are dramatical changed in hypomyelination model rat and in demyelination region of stroke model mice. The review demonstrate microtubule and its binding partner Tau might be necessary for oligodendrocyte function based on previous reports.
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Affiliation(s)
- Tomohiro Torii
- Laboratory of Ion Channel Pathophysiology, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- Center for Research in Neurodegenerative Diseases, Doshisha University, Kyoto, Japan
- *Correspondence: Tomohiro Torii, ; Hiroaki Misonou,
| | - Tomohiro Miyasaka
- Center for Research in Neurodegenerative Diseases, Doshisha University, Kyoto, Japan
- Department of Neuropathology, Faculty of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Hiroaki Misonou
- Laboratory of Ion Channel Pathophysiology, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- Center for Research in Neurodegenerative Diseases, Doshisha University, Kyoto, Japan
- *Correspondence: Tomohiro Torii, ; Hiroaki Misonou,
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15
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Gusdon AM, Faraday N, Aita JS, Kumar S, Mehta I, Choi HA, Cleland JL, Robinson K, McCullough LD, Ng DK, Kannan RM, Kannan S. Dendrimer nanotherapy for severe COVID-19 attenuates inflammation and neurological injury markers and improves outcomes in a phase2a clinical trial. Sci Transl Med 2022; 14:eabo2652. [PMID: 35857827 DOI: 10.1126/scitranslmed.abo2652] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hyperinflammation triggered by SARS-CoV-2 is a major cause of disease severity, with activated macrophages implicated in this response. OP-101, a hydroxyl-polyamidoamine dendrimer-N-acetylcysteine conjugate that specifically targets activated macrophages, improves outcomes in preclinical models of systemic inflammation and neuroinflammation. In this multicenter, randomized, double-blind, placebo-controlled, adaptive phase 2a trial, we evaluated safety and preliminary efficacy of OP-101 in patients with severe COVID-19. Twenty-four patients classified as having severe COVID-19 with a baseline World Health Organization seven-point ordinal scale of ≥5 were randomized to receive a single intravenous dose of placebo (n = 7 patients) or OP-101 at 2 (n = 6), 4 (n = 6), or 8 mg/kg (n = 5 patients). All study participants received standard of care, including corticosteroids. OP-101 at 4 mg/kg was better than placebo at decreasing inflammatory markers; OP-101 at 4 and 8 mg/kg was better than placebo at reducing neurological injury markers, (neurofilament light chain and glial fibrillary acidic protein). Risk for the composite outcome of mechanical ventilation or death at 30 and 60 days after treatment was 71% (95% CI: 29%, 96%) for placebo and 18% (95% CI: 4%, 43%; P = 0.021) for the pooled OP-101 treatment arms. At 60 days, 3 of 7 patients given placebo and 14 of 17 OP-101-treated patients were surviving. No drug-related adverse events were reported. These data show that OP-101 was well tolerated and may have potential to treat systemic inflammation and neuronal injury, reducing morbidity and mortality in hospitalized patients with severe COVID-19.
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Affiliation(s)
- Aaron M Gusdon
- Department of Neurosurgery, The University of Texas, McGovern Medical School, Memorial Hermann Hospital, Houston, TX, USA
| | - Nauder Faraday
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - John S Aita
- Avera McKennan Hospital and University Health Center, Sioux Falls, SD, USA
| | - Sunil Kumar
- Broward Health Medical Center, Fort Lauderdale, FL, USA
| | - Ishan Mehta
- Emory University School of Medicine, Atlanta, GA, USA
| | - HuiMahn A Choi
- Department of Neurosurgery, The University of Texas, McGovern Medical School, Memorial Hermann Hospital, Houston, TX, USA
| | | | | | - Louise D McCullough
- Department of Neurology, The University of Texas, McGovern Medical School, Memorial Hermann Hospital, Houston, TX, USA
| | - Derek K Ng
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Rangaramanujam M Kannan
- Department of Ophthalmology, Center for Nanomedicine, Wilmer Eye Institute, Johns Hopkins University SOM, Baltimore, MD, USA
| | - Sujatha Kannan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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16
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Ingham DJ, Hillyer KM, McGuire MJ, Gamblin TC. In vitro Tau Aggregation Inducer Molecules Influence the Effects of MAPT Mutations on Aggregation Dynamics. Biochemistry 2022; 61:1243-1259. [PMID: 35731895 PMCID: PMC9260964 DOI: 10.1021/acs.biochem.2c00111] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 06/01/2022] [Indexed: 11/28/2022]
Abstract
Alzheimer's disease (AD) and Alzheimer's disease-related dementias (ADRDs) affect 6 million Americans, and they are projected to have an estimated health care cost of $355 billion for 2021. A histopathological hallmark of AD and many ADRDs is the aberrant intracellular accumulation of the microtubule-associated protein tau. These neurodegenerative disorders that contain tau aggregates are collectively known as tauopathies, and recent structural studies have shown that different tauopathies are characterized by different "strains" of tau filaments. In addition, mutations in the gene that encodes for tau protein expression have been associated with a group of tauopathies known as frontotemporal dementias with parkinsonism linked to chromosome 17 (FTDP-17 or familial frontotemporal dementia). In vitro studies often use small molecules to induce tau aggregation as tau is extremely soluble and does not spontaneously aggregate under typical laboratory conditions, and the use of authentic filaments to conduct in vitro studies is not feasible. This study highlights how different inducer molecules can have fundamental disparities to how disease-related mutations affect the aggregation dynamics of tau. Using three different classes of tau aggregation inducer molecules, we characterized disease-relevant mutations in tau's PGGG motifs at positions P301S, P332S, and P364S. When comparing these mutations to wild-type tau, we found that depending on the type of inducer molecule used, we saw fundamental differences in total aggregation, aggregation kinetics, immunoreactivity, and filament numbers, length, and width. These data are consistent with the possibility that different tau aggregation inducer molecules make different structural polymorphs, although this possibility would need to be confirmed by high-resolution techniques such as cryo-electron microscopy. The data also show that disease-associated missense mutations in tau impact tau aggregation differently depending on the mechanism of aggregation induction.
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Affiliation(s)
- David J. Ingham
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, 66045, United States
| | - Kelsey M. Hillyer
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, 66045, United States
| | - Madison J. McGuire
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, 66045, United States
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17
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Fader KA, Pardo ID, Kovi RC, Somps CJ, Wang HH, Vaidya VS, Ramaiah SK, Sirivelu MP. Circulating neurofilament light chain as a promising biomarker of AAV-induced dorsal root ganglia toxicity in nonclinical toxicology species. Mol Ther Methods Clin Dev 2022; 25:264-277. [PMID: 35505662 PMCID: PMC9024379 DOI: 10.1016/j.omtm.2022.03.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/27/2022] [Indexed: 12/14/2022]
Abstract
Adeno-associated virus (AAV)-induced dorsal root ganglia (DRG) toxicity has been observed in several nonclinical species, where lesions are characterized by neuronal degeneration/necrosis, nerve fiber degeneration, and mononuclear cell infiltration. As AAV vectors become an increasingly common platform for novel therapeutics, non-invasive biomarkers are needed to better characterize and manage the risk of DRG neurotoxicity in both nonclinical and clinical studies. Based on biological relevance, reagent availability, antibody cross-reactivity, DRG protein expression, and assay performance, neurofilament light chain (NF-L) emerged as a promising biomarker candidate. Dose- and time-dependent changes in NF-L were evaluated in male Wistar Han rats and cynomolgus monkeys following intravenous or intrathecal AAV injection, respectively. NF-L profiles were then compared against microscopic DRG lesions on day 29 post-dosing. In animals exhibiting DRG toxicity, plasma/serum NF-L was strongly associated with the severity of neuronal degeneration/necrosis and nerve fiber degeneration, with elevations beginning as early as day 8 in rats (≥5 × 1013 vg/kg) and day 14 in monkeys (≥3.3 × 1013 vg/dose). Consistent with the unique positioning of DRGs outside the blood-brain barrier, NF-L in cerebrospinal fluid was only weakly associated with DRG findings. In summary, circulating NF-L is a promising biomarker of AAV-induced DRG toxicity in nonclinical species.
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Affiliation(s)
- Kelly A Fader
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Groton, CT 06340, USA
| | | | - Ramesh C Kovi
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Pfizer Inc., 300 Technology Square, Cambridge, MA 02139, USA
| | - Christopher J Somps
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Groton, CT 06340, USA
| | - Helen Hong Wang
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Pfizer Inc., 300 Technology Square, Cambridge, MA 02139, USA
| | - Vishal S Vaidya
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Pfizer Inc., 300 Technology Square, Cambridge, MA 02139, USA
| | - Shashi K Ramaiah
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Pfizer Inc., 300 Technology Square, Cambridge, MA 02139, USA
| | - Madhu P Sirivelu
- Pfizer Worldwide Research, Development and Medical, Drug Safety Research and Development, Pfizer Inc., 300 Technology Square, Cambridge, MA 02139, USA
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18
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Frontotemporal Lobar Dementia Mutant Tau Impairs Axonal Transport through a Protein Phosphatase 1γ-Dependent Mechanism. J Neurosci 2021; 41:9431-9451. [PMID: 34607969 PMCID: PMC8580143 DOI: 10.1523/jneurosci.1914-20.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/19/2021] [Accepted: 08/21/2021] [Indexed: 11/21/2022] Open
Abstract
Pathologic tau modifications are characteristic of Alzheimer's disease and related dementias, but mechanisms of tau toxicity continue to be debated. Inherited mutations in tau cause early onset frontotemporal lobar dementias (FTLD-tau) and are commonly used to model mechanisms of tau toxicity in tauopathies. Previous work in the isolated squid axoplasm model demonstrated that several pathogenic forms of tau inhibit axonal transport through a mechanism involving activation of protein phosphatase 1 (PP1). Here, we determined that P301L and R5L FTLD mutant tau proteins elicit a toxic effect on axonal transport as monomeric proteins. We evaluated interactions of wild-type or mutant tau with specific PP1 isoforms (α, β, and γ) to examine how the interaction contributes to this toxic effect using primary rat hippocampal neurons from both sexes. Pull-down and bioluminescence resonance energy transfer experiments revealed selective interactions of wild-type tau with PP1α and PP1γ isoforms, but not PP1β, which were significantly increased by the P301L tau mutation. The results from proximity ligation assays confirmed the interaction in primary hippocampal neurons. Moreover, expression of FTLD-linked mutant tau in these neurons enhanced levels of active PP1, also increasing the pausing frequency of fluorescently labeled vesicles in both anterograde and retrograde directions. Knockdown of PP1γ, but not PP1α, rescued the cargo-pausing effects of P301L and R5L tau, a result replicated by deleting a phosphatase-activating domain in the amino terminus of P301L tau. These findings support a model of tau toxicity involving aberrant activation of a specific PP1γ-dependent pathway that disrupts axonal transport in neurons. SIGNIFICANCE STATEMENT Tau pathology is closely associated with neurodegeneration in Alzheimer's disease and other tauopathies, but the toxic mechanisms remain a debated topic. We previously proposed that pathologic tau forms induce dysfunction and degeneration through aberrant activation of a PP1-dependent pathway that disrupts axonal transport. Here, we show that tau directly interacts with specific PP1 isoforms, increasing levels of active PP1. Pathogenic tau mutations enhance this interaction, further increasing active PP1 levels and impairing axonal transport in isolated squid axoplasm and primary hippocampal neurons. Mutant-tau-mediated impairment of axonal transport was mediated by PP1γ and a phosphatase-activating domain located at the amino terminus of tau. This work has important implications for understanding and potentially mitigating tau-mediated neurotoxicity in tauopathies.
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19
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Super-resolution microscopy: a closer look at synaptic dysfunction in Alzheimer disease. Nat Rev Neurosci 2021; 22:723-740. [PMID: 34725519 DOI: 10.1038/s41583-021-00531-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2021] [Indexed: 11/08/2022]
Abstract
The synapse has emerged as a critical neuronal structure in the degenerative process of Alzheimer disease (AD), in which the pathogenic signals of two key players - amyloid-β (Aβ) and tau - converge, thereby causing synaptic dysfunction and cognitive deficits. The synapse presents a dynamic, confined microenvironment in which to explore how key molecules travel, localize, interact and assume different levels of organizational complexity, thereby affecting neuronal function. However, owing to their small size and the diffraction-limited resolution of conventional light microscopic approaches, investigating synaptic structure and dynamics has been challenging. Super-resolution microscopy (SRM) techniques have overcome the resolution barrier and are revolutionizing our quantitative understanding of biological systems in unprecedented spatio-temporal detail. Here we review critical new insights provided by SRM into the molecular architecture and dynamic organization of the synapse and, in particular, the interactions between Aβ and tau in this compartment. We further highlight how SRM can transform our understanding of the molecular pathological mechanisms that underlie AD. The application of SRM for understanding the roles of synapses in AD pathology will provide a stepping stone towards a broader understanding of dysfunction in other subcellular compartments and at cellular and circuit levels in this disease.
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20
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Van Acker ZP, Perdok A, Bretou M, Annaert W. The microglial lysosomal system in Alzheimer's disease: Guardian against proteinopathy. Ageing Res Rev 2021; 71:101444. [PMID: 34391945 DOI: 10.1016/j.arr.2021.101444] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/14/2021] [Accepted: 08/08/2021] [Indexed: 12/12/2022]
Abstract
Microglia, the brain-resident immune cells, play an essential role in the upkeep of brain homeostasis. They actively adapt into specific activation states based on cues from the microenvironment. One of these encompasses the activated response microglia (ARMs) phenotype. It arises along a healthy aging process and in a range of neurodegenerative diseases, including Alzheimer's disease (AD). As the phenotype is characterized by an increased lipid metabolism, phagocytosis rate, lysosomal protease content and secretion of neuroprotective agents, it leaves to reason that the phenotype is adapted in an attempt to restore homeostasis. This is important to the conundrum of inflammatory processes. Inflammation per se may not be deleterious; it is only when microglial reactions become chronic or the microglial subtype is made dysfunctional by (multiple) risk proteins with single-nucleotide polymorphisms that microglial involvement becomes deleterious instead of beneficial. Interestingly, the ARMs up- and downregulate many late-onset AD-associated risk factor genes, the products of which are particularly active in the endolysosomal system. Hence, in this review, we focus on how the endolysosomal system is placed at the crossroad of inflammation and microglial capacity to keep pace with degradation.
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