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Robles-Gómez ÁA, Ordaz B, Lorea-Hernández JJ, Peña-Ortega F. Deleterious and protective effects of epothilone-D alone and in the context of amyloid β- and tau-induced alterations. Front Mol Neurosci 2023; 16:1198299. [PMID: 37900942 PMCID: PMC10603193 DOI: 10.3389/fnmol.2023.1198299] [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: 04/01/2023] [Accepted: 09/20/2023] [Indexed: 10/31/2023] Open
Abstract
Amyloid-β (Aβ) and hyperphosphorylated tau (P-tau) are Alzheimer's disease (AD) biomarkers that interact in a complex manner to induce most of the cognitive and brain alterations observed in this disease. Since the neuronal cytoskeleton is a common downstream pathological target of tau and Aβ, which mostly lead to augmented microtubule instability, the administration of microtubule stabilizing agents (MSAs) can protect against their pathological actions. However, the effectiveness of MSAs is still uncertain due to their state-dependent negative effects; thus, evaluating their specific actions in different pathological or physiological conditions is required. We evaluated whether epothilone-D (Epo-D), a clinically used MSA, rescues from the functional and behavioral alterations produced by intracerebroventricular injection of Aβ, the presence of P-tau, or their combination in rTg4510 mice. We also explored the side effects of Epo-D. To do so, we evaluated hippocampal-dependent spatial memory with the Hebb-Williams maze, hippocampal CA1 integrity and the intrinsic and synaptic properties of CA1 pyramidal neurons with the patch-clamp technique. Aβ and P-tau mildly impaired memory retrieval, but produced contrasting effects on intrinsic excitability. When Aβ and P-tau were combined, the alterations in excitability and spatial reversal learning (i.e., cognitive flexibility) were exacerbated. Interestingly, Epo-D prevented most of the impairments induced Aβ and P-tau alone and combined. However, Epo-D also exhibited some side effects depending on the prevailing pathological or physiological condition, which should be considered in future preclinical and translational studies. Although we did not perform extensive histopathological evaluations or measured microtubule stability, our findings show that MSAs can rescue the consequences of AD-like conditions but otherwise be harmful if administered at a prodromal stage of the disease.
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Affiliation(s)
- Ángel Abdiel Robles-Gómez
- Instituto de Neurobiología, UNAM Campus Juriquilla, Querétaro, Mexico
- Posgrado en Ciencias Biológicas, UNAM, Ciudad Universitaria, México City, Mexico
| | - Benito Ordaz
- Instituto de Neurobiología, UNAM Campus Juriquilla, Querétaro, Mexico
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2
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Song Y, Tsai MY, Wang B, Comassio P, Moreira JE, Kriefall N, Morfini G, Brady S. Divergent Molecular Pathways for Toxicity of Selected Mutant C9ORF72-derived Dipeptide Repeats. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.28.558663. [PMID: 37808871 PMCID: PMC10557653 DOI: 10.1101/2023.09.28.558663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Expansion of a hexanucleotide repeat in a noncoding region of the C9ORF72 gene is responsible for a significant fraction of Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) cases, but identifying specific toxic gene products and mechanisms has been difficult. Pathogenesis was proposed to involve the production of toxic RNA species and/or accumulation of toxic dipeptide repeats (DPRs), but distinguishing between these mechanisms has been challenging. In this study, we first use complementary model systems for analyzing pathogenesis in adult-onset neurodegenerative diseases to characterize the pathogenicity of DPRs produced by Repeat Associated Non-ATG (RAN) translation of C9ORF72 in specific cellular compartments: isolated axoplasm and giant synapse from the squid. Results showed selective axonal and presynaptic toxicity of GP-DPRs, independent of associated RNA. These effects involved downstream ASK1 signaling pathways that affect fast axonal transport and synaptic function, a pathogenic mechanism shared with other mutant proteins associated with familial ALS, like SOD1 and FUS. These pathways are sufficient to produce the "dying-back" axonopathy seen in ALS. However, other mutant genes (e.g., SOD1) that activate this mechanism rarely produce FTD. When parallel studies in primary motor neurons from rats were conducted, an additional pathogenic mechanism was revealed. The GR- and PR-DPRs, which had no effect on axonal transport or synaptic transmission, were found to disrupt the nuclei of transfected neurons, leading to "dying-forward" neuropathy. All C9-DRP-mediated toxic effects observed here are independent of whether the corresponding mRNAs contained hexanucleotide repeats or alternative codons. These studies establish the divergent toxicity of C9-DPRs that cause neurodegeneration in ALS and FTD, suggesting that these two independent pathogenic mechanisms may contribute to disease heterogeneity and/or synergize on disease progression in C9ORF72 patients with both ALS and FTD symptoms. Abstract Figure
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3
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Cario A, Berger CL. Tau, microtubule dynamics, and axonal transport: New paradigms for neurodegenerative disease. Bioessays 2023; 45:e2200138. [PMID: 37489532 PMCID: PMC10630968 DOI: 10.1002/bies.202200138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 05/04/2023] [Accepted: 05/23/2023] [Indexed: 07/26/2023]
Abstract
The etiology of Tauopathies, a diverse class of neurodegenerative diseases associated with the Microtubule Associated Protein (MAP) Tau, is usually described by a common mechanism in which Tau dysfunction results in the loss of axonal microtubule stability. Here, we reexamine and build upon the canonical disease model to encompass other Tau functions. In addition to regulating microtubule dynamics, Tau acts as a modulator of motor proteins, a signaling hub, and a scaffolding protein. This diverse array of functions is related to the dynamic nature of Tau isoform expression, post-translational modification (PTM), and conformational flexibility. Thus, there is no single mechanism that can describe Tau dysfunction. The effects of specific pathogenic mutations or aberrant PTMs need to be examined on all of the various functions of Tau in order to understand the unique etiology of each disease state.
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Affiliation(s)
- Alisa Cario
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405
| | - Christopher L. Berger
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405
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4
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Zhang Y, Chen H, Li R, Sterling K, Song W. Amyloid β-based therapy for Alzheimer's disease: challenges, successes and future. Signal Transduct Target Ther 2023; 8:248. [PMID: 37386015 PMCID: PMC10310781 DOI: 10.1038/s41392-023-01484-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 58.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 07/01/2023] Open
Abstract
Amyloid β protein (Aβ) is the main component of neuritic plaques in Alzheimer's disease (AD), and its accumulation has been considered as the molecular driver of Alzheimer's pathogenesis and progression. Aβ has been the prime target for the development of AD therapy. However, the repeated failures of Aβ-targeted clinical trials have cast considerable doubt on the amyloid cascade hypothesis and whether the development of Alzheimer's drug has followed the correct course. However, the recent successes of Aβ targeted trials have assuaged those doubts. In this review, we discussed the evolution of the amyloid cascade hypothesis over the last 30 years and summarized its application in Alzheimer's diagnosis and modification. In particular, we extensively discussed the pitfalls, promises and important unanswered questions regarding the current anti-Aβ therapy, as well as strategies for further study and development of more feasible Aβ-targeted approaches in the optimization of AD prevention and treatment.
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Affiliation(s)
- Yun Zhang
- National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China.
| | - Huaqiu Chen
- National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Ran Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Keenan Sterling
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Weihong Song
- National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China.
- The Second Affiliated Hospital and Yuying Children's Hospital, Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Wenzhou Medical University, Wenzhou, Zhejiang, China.
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, Zhejiang, China.
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5
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Saunders TS, Pozzolo FE, Heslegrave A, King D, McGeachan RI, Spires-Jones MP, Harris SE, Ritchie C, Muniz-Terrera G, Deary IJ, Cox SR, Zetterberg H, Spires-Jones TL. Predictive blood biomarkers and brain changes associated with age-related cognitive decline. Brain Commun 2023; 5:fcad113. [PMID: 37180996 PMCID: PMC10167767 DOI: 10.1093/braincomms/fcad113] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 12/28/2022] [Accepted: 04/05/2023] [Indexed: 04/08/2023] Open
Abstract
Growing evidence supports the use of plasma levels of tau phosphorylated at threonine 181, amyloid-β, neurofilament light and glial fibrillary acidic protein as promising biomarkers for Alzheimer's disease. While these blood biomarkers are promising for distinguishing people with Alzheimer's disease from healthy controls, their predictive validity for age-related cognitive decline without dementia remains unclear. Further, while tau phosphorylated at threonine 181 is a promising biomarker, the distribution of this phospho-epitope of tau in the brain is unknown. Here, we tested whether plasma levels of tau phosphorylated at threonine 181, amyloid-β, neurofilament light and fibrillary acidic protein predict cognitive decline between ages 72 and 82 in 195 participants in the Lothian birth cohorts 1936 study of cognitive ageing. We further examined post-mortem brain samples from temporal cortex to determine the distribution of tau phosphorylated at threonine 181 in the brain. Several forms of tau phosphorylated at threonine 181 have been shown to contribute to synapse degeneration in Alzheimer's disease, which correlates closely with cognitive decline in this form of dementia, but to date, there have not been investigations of whether tau phosphorylated at threonine 181 is found in synapses in Alzheimer's disease or healthy ageing brain. It was also previously unclear whether tau phosphorylated at threonine 181 accumulated in dystrophic neurites around plaques, which could contribute to tau leakage to the periphery due to impaired membrane integrity in dystrophies. Brain homogenate and biochemically enriched synaptic fractions were examined with western blot to examine tau phosphorylated at threonine 181 levels between groups (n = 10-12 per group), and synaptic and astrocytic localization of tau phosphorylated at threonine 181 were examined using array tomography (n = 6-15 per group), and localization of tau phosphorylated at threonine 181 in plaque-associated dystrophic neurites with associated gliosis were examined with standard immunofluorescence (n = 8-9 per group). Elevated baseline plasma tau phosphorylated at threonine 181, neurofilament light and fibrillary acidic protein predicted steeper general cognitive decline during ageing. Further, increasing tau phosphorylated at threonine 181 over time predicted general cognitive decline in females only. Change in plasma tau phosphorylated at threonine 181 remained a significant predictor of g factor decline when taking into account Alzheimer's disease polygenic risk score, indicating that the increase of blood tau phosphorylated at threonine 181 in this cohort was not only due to incipient Alzheimer's disease. Tau phosphorylated at threonine 181 was observed in synapses and astrocytes in both healthy ageing and Alzheimer's disease brain. We observed that a significantly higher proportion of synapses contain tau phosphorylated at threonine 181 in Alzheimer's disease relative to aged controls. Aged controls with pre-morbid lifetime cognitive resilience had significantly more tau phosphorylated at threonine 181 in fibrillary acidic protein-positive astrocytes than those with pre-morbid lifetime cognitive decline. Further, tau phosphorylated at threonine 181 was found in dystrophic neurites around plaques and in some neurofibrillary tangles. The presence of tau phosphorylated at threonine 181 in plaque-associated dystrophies may be a source of leakage of tau out of neurons that eventually enters the blood. Together, these data indicate that plasma tau phosphorylated at threonine 181, neurofilament light and fibrillary acidic protein may be useful biomarkers of age-related cognitive decline, and that efficient clearance of tau phosphorylated at threonine 181 by astrocytes may promote cognitive resilience.
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Affiliation(s)
- Tyler S Saunders
- UK Dementia Research Institute and Centre for Discovery Brain Sciences at the University of Edinburgh, Edinburgh, EH8 9JZ, UK
- Edinburgh Dementia Prevention & Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Francesca E Pozzolo
- UK Dementia Research Institute and Centre for Discovery Brain Sciences at the University of Edinburgh, Edinburgh, EH8 9JZ, UK
| | - Amanda Heslegrave
- United Kingdom UK Dementia Research Institute at University College London, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Declan King
- UK Dementia Research Institute and Centre for Discovery Brain Sciences at the University of Edinburgh, Edinburgh, EH8 9JZ, UK
| | - Robert I McGeachan
- UK Dementia Research Institute and Centre for Discovery Brain Sciences at the University of Edinburgh, Edinburgh, EH8 9JZ, UK
| | - Maxwell P Spires-Jones
- UK Dementia Research Institute and Centre for Discovery Brain Sciences at the University of Edinburgh, Edinburgh, EH8 9JZ, UK
| | - Sarah E Harris
- Lothian Birth Cohort studies, Department of Psychology, University of Edinburgh, Edinburgh, EH8 9AD, UK
| | - Craig Ritchie
- Edinburgh Dementia Prevention & Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Graciela Muniz-Terrera
- Edinburgh Dementia Prevention & Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH4 2XU, UK
- Department of Social Medicine, Ohio University, Athens, Ohio 45701, USA
- Latin American Institute for Brain Health (BrainLat), Universidad Adolfo Ibanez, Santiago 3485, Chile
| | - Ian J Deary
- Lothian Birth Cohort studies, Department of Psychology, University of Edinburgh, Edinburgh, EH8 9AD, UK
| | - Simon R Cox
- Lothian Birth Cohort studies, Department of Psychology, University of Edinburgh, Edinburgh, EH8 9AD, UK
| | - Henrik Zetterberg
- United Kingdom UK Dementia Research Institute at University College London, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, S-431 80 Molndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Molndal, Sweden
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
| | - Tara L Spires-Jones
- UK Dementia Research Institute and Centre for Discovery Brain Sciences at the University of Edinburgh, Edinburgh, EH8 9JZ, UK
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6
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Meftah S, Gan J. Alzheimer’s disease as a synaptopathy: Evidence for dysfunction of synapses during disease progression. Front Synaptic Neurosci 2023; 15:1129036. [PMID: 36970154 PMCID: PMC10033629 DOI: 10.3389/fnsyn.2023.1129036] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/23/2023] [Indexed: 03/11/2023] Open
Abstract
The synapse has consistently been considered a vulnerable and critical target within Alzheimer’s disease, and synapse loss is, to date, one of the main biological correlates of cognitive decline within Alzheimer’s disease. This occurs prior to neuronal loss with ample evidence that synaptic dysfunction precedes this, in support of the idea that synaptic failure is a crucial stage within disease pathogenesis. The two main pathological hallmarks of Alzheimer’s disease, abnormal aggregates of amyloid or tau proteins, have had demonstrable effects on synaptic physiology in animal and cellular models of Alzheimer’s disease. There is also growing evidence that these two proteins may have a synergistic effect on neurophysiological dysfunction. Here, we review some of the main findings of synaptic alterations in Alzheimer’s disease, and what we know from Alzheimer’s disease animal and cellular models. First, we briefly summarize some of the human evidence to suggest that synapses are altered, including how this relates to network activity. Subsequently, animal and cellular models of Alzheimer’s disease are considered, highlighting mouse models of amyloid and tau pathology and the role these proteins may play in synaptic dysfunction, either in isolation or examining how the two pathologies may interact in dysfunction. This specifically focuses on neurophysiological function and dysfunction observed within these animal models, typically measured using electrophysiology or calcium imaging. Following synaptic dysfunction and loss, it would be impossible to imagine that this would not alter oscillatory activity within the brain. Therefore, this review also discusses how this may underpin some of the aberrant oscillatory patterns seen in animal models of Alzheimer’s disease and human patients. Finally, an overview of some key directions and considerations in the field of synaptic dysfunction in Alzheimer’s disease is covered. This includes current therapeutics that are targeted specifically at synaptic dysfunction, but also methods that modulate activity to rescue aberrant oscillatory patterns. Other important future avenues of note in this field include the role of non-neuronal cell types such as astrocytes and microglia, and mechanisms of dysfunction independent of amyloid and tau in Alzheimer’s disease. The synapse will certainly continue to be an important target within Alzheimer’s disease for the foreseeable future.
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Affiliation(s)
- Soraya Meftah
- UK Dementia Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Jian Gan
- UK Dementia Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom
- *Correspondence: Jian Gan,
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7
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Tzioras M, McGeachan RI, Durrant CS, Spires-Jones TL. Synaptic degeneration in Alzheimer disease. Nat Rev Neurol 2023; 19:19-38. [PMID: 36513730 DOI: 10.1038/s41582-022-00749-z] [Citation(s) in RCA: 68] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2022] [Indexed: 12/15/2022]
Abstract
Alzheimer disease (AD) is characterized by progressive cognitive decline in older individuals accompanied by the presence of two pathological protein aggregates - amyloid-β and phosphorylated tau - in the brain. The disease results in brain atrophy caused by neuronal loss and synapse degeneration. Synaptic loss strongly correlates with cognitive decline in both humans and animal models of AD. Indeed, evidence suggests that soluble forms of amyloid-β and tau can cause synaptotoxicity and spread through neural circuits. These pathological changes are accompanied by an altered phenotype in the glial cells of the brain - one hypothesis is that glia excessively ingest synapses and modulate the trans-synaptic spread of pathology. To date, effective therapies for the treatment or prevention of AD are lacking, but understanding how synaptic degeneration occurs will be essential for the development of new interventions. Here, we highlight the mechanisms through which synapses degenerate in the AD brain, and discuss key questions that still need to be answered. We also cover the ways in which our understanding of the mechanisms of synaptic degeneration is leading to new therapeutic approaches for AD.
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Affiliation(s)
- Makis Tzioras
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK.,UK Dementia Research Institute, The University of Edinburgh, Edinburgh, UK
| | - Robert I McGeachan
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK.,UK Dementia Research Institute, The University of Edinburgh, Edinburgh, UK.,The Hospital for Small Animals, Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, UK
| | - Claire S Durrant
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK.,UK Dementia Research Institute, The University of Edinburgh, Edinburgh, UK
| | - Tara L Spires-Jones
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK. .,UK Dementia Research Institute, The University of Edinburgh, Edinburgh, UK.
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8
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Saroja SR, Sharma A, Hof PR, Pereira AC. Differential expression of tau species and the association with cognitive decline and synaptic loss in Alzheimer's disease. Alzheimers Dement 2022; 18:1602-1615. [PMID: 34873815 PMCID: PMC9170833 DOI: 10.1002/alz.12518] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/03/2021] [Accepted: 10/13/2021] [Indexed: 01/24/2023]
Abstract
Pathological tau proteins in patients with Alzheimer's disease (AD) mainly accumulate in the form of neurofibrillary tangles (NFTs) and neuritic plaques (NPs). However, the molecular properties of tau species present in NFTs and NPs are not known. We tested the hypothesis that tau species within NFT-predominant tissue (NFT_AD) are distinct and more toxic than those in NP-predominant tissue (NP_AD). We analyzed the tau species from post mortem prefrontal cortical brains of NFT_AD and NP_AD. Compared to NP_AD, NFT_AD displayed highly phosphorylated tau oligomers, possessed tau oligomers in extracellular vesicles, and the 3-repeat (3R) and 4-repeat (4R) isoforms were differentially expressed between the groups. Comparison of tau proteins isolated from NFT- versus NP-AD subjects demonstrated higher tau seeding activity in NFT subjects and a greater degree of inducing synaptic loss in cultured neurons. We propose that tau species from NFT-predominant tissues possess greater levels of degenerative properties, thereby causing synaptic loss and cognitive decline.
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Affiliation(s)
- Sivaprakasam R. Saroja
- Department of Neurology, Icahn School of MedicineMount SinaiNew YorkNew YorkUSA
- Nash Family Department of Neuroscience and Friedman Brain InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Abhijeet Sharma
- Department of Neurology, Icahn School of MedicineMount SinaiNew YorkNew YorkUSA
- Nash Family Department of Neuroscience and Friedman Brain InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Patrick R. Hof
- Nash Family Department of Neuroscience and Friedman Brain InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Ronald M. Loeb Center for Alzheimer's DiseaseIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Ana C. Pereira
- Department of Neurology, Icahn School of MedicineMount SinaiNew YorkNew YorkUSA
- Nash Family Department of Neuroscience and Friedman Brain InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Ronald M. Loeb Center for Alzheimer's DiseaseIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
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9
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Wu M, Zhang M, Yin X, Chen K, Hu Z, Zhou Q, Cao X, Chen Z, Liu D. The role of pathological tau in synaptic dysfunction in Alzheimer's diseases. Transl Neurodegener 2021; 10:45. [PMID: 34753506 PMCID: PMC8579533 DOI: 10.1186/s40035-021-00270-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/25/2021] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disease characterized by progressive cognitive decline, accompanied by amyloid-β (Aβ) overload and hyperphosphorylated tau accumulation in the brain. Synaptic dysfunction, an important pathological hallmark in AD, is recognized as the main cause of the cognitive impairments. Accumulating evidence suggests that synaptic dysfunction could be an early pathological event in AD. Pathological tau, which is detached from axonal microtubules and mislocalized into pre- and postsynaptic neuronal compartments, is suggested to induce synaptic dysfunction in several ways, including reducing mobility and release of presynaptic vesicles, decreasing glutamatergic receptors, impairing the maturation of dendritic spines at postsynaptic terminals, disrupting mitochondrial transport and function in synapses, and promoting the phagocytosis of synapses by microglia. Here, we review the current understanding of how pathological tau mediates synaptic dysfunction and contributes to cognitive decline in AD. We propose that elucidating the mechanism by which pathological tau impairs synaptic function is essential for exploring novel therapeutic strategies for AD.
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Affiliation(s)
- Moxin Wu
- Department of Medical Laboratory, Affiliated Hospital of Jiujiang University, Jiujiang, 332000, China.,Jiujiang Clinical Precision Medicine Research Center, Jiujiang, 332000, China
| | - Manqing Zhang
- Medical College of Jiujiang University, Jiujiang, 332000, China
| | - Xiaoping Yin
- Jiujiang Clinical Precision Medicine Research Center, Jiujiang, 332000, China.,Department of Neurology, Affiliated Hospital of Jiujiang University, Jiujiang, 332000, China
| | - Kai Chen
- Department of Dermatology, Wuhan No. 1 Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Zhijian Hu
- Department of Medical Laboratory, Affiliated Hospital of Jiujiang University, Jiujiang, 332000, China
| | - Qin Zhou
- Jiujiang Clinical Precision Medicine Research Center, Jiujiang, 332000, China
| | - Xianming Cao
- Jiujiang Clinical Precision Medicine Research Center, Jiujiang, 332000, China.,Department of Neurology, Affiliated Hospital of Jiujiang University, Jiujiang, 332000, China
| | - Zhiying Chen
- Jiujiang Clinical Precision Medicine Research Center, Jiujiang, 332000, China. .,Department of Neurology, Affiliated Hospital of Jiujiang University, Jiujiang, 332000, China.
| | - Dan Liu
- Department of Medical Genetics, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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10
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Siano G, Falcicchia C, Origlia N, Cattaneo A, Di Primio C. Non-Canonical Roles of Tau and Their Contribution to Synaptic Dysfunction. Int J Mol Sci 2021; 22:ijms221810145. [PMID: 34576308 PMCID: PMC8466023 DOI: 10.3390/ijms221810145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/12/2021] [Accepted: 09/17/2021] [Indexed: 12/13/2022] Open
Abstract
Tau plays a central role in a group of neurodegenerative disorders collectively named tauopathies. Despite the wide range of diverse symptoms at the onset and during the progression of the pathology, all tauopathies share two common hallmarks, namely the misfolding and aggregation of Tau protein and progressive synaptic dysfunctions. Tau aggregation correlates with cognitive decline and behavioural impairment. The mechanistic link between Tau misfolding and the synaptic dysfunction is still unknown, but this correlation is well established in the human brain and also in tauopathy mouse models. At the onset of the pathology, Tau undergoes post-translational modifications (PTMs) inducing the detachment from the cytoskeleton and its release in the cytoplasm as a soluble monomer. In this condition, the physiological enrichment in the axon is definitely disrupted, resulting in Tau relocalization in the cell soma and in dendrites. Subsequently, Tau aggregates into toxic oligomers and amyloidogenic forms that disrupt synaptic homeostasis and function, resulting in neuronal degeneration. The involvement of Tau in synaptic transmission alteration in tauopathies has been extensively reviewed. Here, we will focus on non-canonical Tau functions mediating synapse dysfunction.
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Affiliation(s)
- Giacomo Siano
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
| | - Chiara Falcicchia
- Institute of Neuroscience, Italian National Research Council, Via Moruzzi 1, 56124 Pisa, Italy; (C.F.); (N.O.)
| | - Nicola Origlia
- Institute of Neuroscience, Italian National Research Council, Via Moruzzi 1, 56124 Pisa, Italy; (C.F.); (N.O.)
| | - Antonino Cattaneo
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
- European Brain Research Institute (EBRI), Fondazione Rita Levi-Montalcini, Viale Regina Elena 295, 00161 Roma, Italy
- Correspondence: (A.C.); (C.D.P.)
| | - Cristina Di Primio
- Institute of Neuroscience, Italian National Research Council, Via Moruzzi 1, 56124 Pisa, Italy; (C.F.); (N.O.)
- Correspondence: (A.C.); (C.D.P.)
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11
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Diociaiuti M, Bonanni R, Cariati I, Frank C, D’Arcangelo G. Amyloid Prefibrillar Oligomers: The Surprising Commonalities in Their Structure and Activity. Int J Mol Sci 2021; 22:ijms22126435. [PMID: 34208561 PMCID: PMC8235680 DOI: 10.3390/ijms22126435] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/10/2021] [Accepted: 06/14/2021] [Indexed: 12/12/2022] Open
Abstract
It has been proposed that a “common core” of pathologic pathways exists for the large family of amyloid-associated neurodegenerations, including Alzheimer’s, Parkinson’s, type II diabetes and Creutzfeldt–Jacob’s Disease. Aggregates of the involved proteins, independently from their primary sequence, induced neuron membrane permeabilization able to trigger an abnormal Ca2+ influx leading to synaptotoxicity, resulting in reduced expression of synaptic proteins and impaired synaptic transmission. Emerging evidence is now focusing on low-molecular-weight prefibrillar oligomers (PFOs), which mimic bacterial pore-forming toxins that form well-ordered oligomeric membrane-spanning pores. At the same time, the neuron membrane composition and its chemical microenvironment seem to play a pivotal role. In fact, the brain of AD patients contains increased fractions of anionic lipids able to favor cationic influx. However, up to now the existence of a specific “common structure” of the toxic aggregate, and a “common mechanism” by which it induces neuronal damage, synaptotoxicity and impaired synaptic transmission, is still an open hypothesis. In this review, we gathered information concerning this hypothesis, focusing on the proteins linked to several amyloid diseases. We noted commonalities in their structure and membrane activity, and their ability to induce Ca2+ influx, neurotoxicity, synaptotoxicity and impaired synaptic transmission.
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Affiliation(s)
- Marco Diociaiuti
- Centro Nazionale Malattie Rare, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
- Correspondence:
| | - Roberto Bonanni
- Department of Systems Medicine, “Tor Vergata” University of Rome, Via Montpellier 1, 00133 Rome, Italy; (R.B.); (G.D.)
| | - Ida Cariati
- PhD in Medical-Surgical Biotechnologies and Translational Medicine, Department of Clinical Sciences and Translational Medicine, “Tor Vergata” University of Rome, Via Montpellier 1, 00133 Rome, Italy;
| | - Claudio Frank
- UniCamillus-Saint Camillus International University of Health Sciences, Via di Sant’Alessandro 8, 00131 Rome, Italy;
| | - Giovanna D’Arcangelo
- Department of Systems Medicine, “Tor Vergata” University of Rome, Via Montpellier 1, 00133 Rome, Italy; (R.B.); (G.D.)
- Centre of Space Bio-Medicine, “Tor Vergata” University of Rome, Via Montpellier 1, 00133 Rome, Italy
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12
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Naveh Tassa S, Ben Zichri S, Lacham-Hartman S, Oren O, Slobodnik Z, Eremenko E, Toiber D, Jelinek R, Papo N. A Mechanism for the Inhibition of Tau Neurotoxicity: Studies with Artificial Membranes, Isolated Mitochondria, and Intact Cells. ACS Chem Neurosci 2021; 12:1563-1577. [PMID: 33904703 DOI: 10.1021/acschemneuro.1c00045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
It is currently believed that molecular agents that specifically bind to and neutralize the toxic proteins/peptides, amyloid β (Aβ42), tau, and the tau-derived peptide PHF6, hold the key to attenuating the progression of Alzheimer's disease (AD). We thus tested our previously developed nonaggregating Aβ42 double mutant (Aβ42DM) as a multispecific binder for three AD-associated molecules, wild-type Aβ42, the tauK174Q mutant, and a synthetic PHF6 peptide. Aβ42DM acted as a functional inhibitor of these molecules in in vitro assays and in neuronal cell-based models of AD. The double mutant bound both cytotoxic tauK174Q and synthetic PHF6 and protected neuronal cells from the accumulation of tau in cell lysates and mitochondria. Aβ42DM also reduced toxic intracellular levels of calcium and the overall cell toxicity induced by overexpressed tau, synthetic PHF6, Aβ42, or a combination of PHF6and Aβ42. Aβ42DM inhibited PHF6-induced overall mitochondrial dysfunction: In particular, Aβ42DM inhibited PHF6-induced damage to submitochondrial particles (SMPs) and suppressed PHF6-induced elevation of the ζ-potential of inverted SMPs (proxy for the inner mitochondrial membrane, IMM). PHF6 reduced the lipid fluidity of cardiolipin/DOPC vesicles (that mimic the IMM) but not DOPC (which mimics the outer mitochondrial membrane), and this effect was inhibited by Aβ42DM. This inhibition may be explained by the conformational changes in PHF6 induced by Aβ42DM in solution and in membrane mimetics. On this basis, the paper presents a mechanistic explanation for the inhibitory activity of Aβ42DM against Aβ42- and tau-induced membrane permeability and cell toxicity and provides confirmatory evidence for its protective function in neuronal cells.
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Affiliation(s)
- Segev Naveh Tassa
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Shani Ben Zichri
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Shiran Lacham-Hartman
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Ofek Oren
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Zeev Slobodnik
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Ekaterina Eremenko
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Debra Toiber
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Raz Jelinek
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Niv Papo
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
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13
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Mueller RL, Combs B, Alhadidy MM, Brady ST, Morfini GA, Kanaan NM. Tau: A Signaling Hub Protein. Front Mol Neurosci 2021; 14:647054. [PMID: 33815057 PMCID: PMC8017207 DOI: 10.3389/fnmol.2021.647054] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/23/2021] [Indexed: 12/23/2022] Open
Abstract
Over four decades ago, in vitro experiments showed that tau protein interacts with and stabilizes microtubules in a phosphorylation-dependent manner. This observation fueled the widespread hypotheses that these properties extend to living neurons and that reduced stability of microtubules represents a major disease-driving event induced by pathological forms of tau in Alzheimer’s disease and other tauopathies. Accordingly, most research efforts to date have addressed this protein as a substrate, focusing on evaluating how specific mutations, phosphorylation, and other post-translational modifications impact its microtubule-binding and stabilizing properties. In contrast, fewer efforts were made to illuminate potential mechanisms linking physiological and disease-related forms of tau to the normal and pathological regulation of kinases and phosphatases. Here, we discuss published work indicating that, through interactions with various kinases and phosphatases, tau may normally act as a scaffolding protein to regulate phosphorylation-based signaling pathways. Expanding on this concept, we also review experimental evidence linking disease-related tau species to the misregulation of these pathways. Collectively, the available evidence supports the participation of tau in multiple cellular processes sustaining neuronal and glial function through various mechanisms involving the scaffolding and regulation of selected kinases and phosphatases at discrete subcellular compartments. The notion that the repertoire of tau functions includes a role as a signaling hub should widen our interpretation of experimental results and increase our understanding of tau biology in normal and disease conditions.
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Affiliation(s)
- Rebecca L Mueller
- Department of Translational Neuroscience, Michigan State University, Grand Rapids, MI, United States.,Neuroscience Program, Michigan State University, East Lansing, MI, United States
| | - Benjamin Combs
- Department of Translational Neuroscience, Michigan State University, Grand Rapids, MI, United States
| | - Mohammed M Alhadidy
- Department of Translational Neuroscience, Michigan State University, Grand Rapids, MI, United States.,Neuroscience Program, Michigan State University, East Lansing, MI, United States
| | - Scott T Brady
- Department of Anatomy and Cell Biology, The University of Illinois at Chicago, Chicago, IL, United States.,Marine Biological Laboratory, Woods Hole, MA, United States
| | - Gerardo A Morfini
- Department of Anatomy and Cell Biology, The University of Illinois at Chicago, Chicago, IL, United States.,Marine Biological Laboratory, Woods Hole, MA, United States
| | - Nicholas M Kanaan
- Department of Translational Neuroscience, Michigan State University, Grand Rapids, MI, United States.,Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, MI, United States
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14
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Cieślik M, Gassowska-Dobrowolska M, Zawadzka A, Frontczak-Baniewicz M, Gewartowska M, Dominiak A, Czapski GA, Adamczyk A. The Synaptic Dysregulation in Adolescent Rats Exposed to Maternal Immune Activation. Front Mol Neurosci 2021; 13:555290. [PMID: 33519375 PMCID: PMC7840660 DOI: 10.3389/fnmol.2020.555290] [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: 04/24/2020] [Accepted: 11/27/2020] [Indexed: 12/18/2022] Open
Abstract
Maternal immune activation (MIA) is a risk factor for neurodevelopmental disorders in offspring, but the pathomechanism is largely unknown. The aim of our study was to analyse the molecular mechanisms contributing to synaptic alterations in hippocampi of adolescent rats exposed prenatally to MIA. MIA was evoked in pregnant female rats by i.p. administration of lipopolysaccharide at gestation day 9.5. Hippocampi of offspring (52-53-days-old rats) were analysed using transmission electron microscopy (TEM), qPCR and Western blotting. Moreover, mitochondrial membrane potential, activity of respiratory complexes, and changes in glutathione system were measured. It was found that MIA induced changes in hippocampi morphology, especially in the ultrastructure of synapses, including synaptic mitochondria, which were accompanied by impairment of mitochondrial electron transport chain and decreased mitochondrial membrane potential. These phenomena were in agreement with increased generation of reactive oxygen species, which was evidenced by a decreased reduced/oxidised glutathione ratio and an increased level of dichlorofluorescein (DCF) oxidation. Activation of cyclin-dependent kinase 5, and phosphorylation of glycogen synthase kinase 3β on Ser9 occurred, leading to its inhibition and, accordingly, to hypophosphorylation of microtubule associated protein tau (MAPT). Abnormal phosphorylation and dysfunction of MAPT, the manager of the neuronal cytoskeleton, harmonised with changes in synaptic proteins. In conclusion, this is the first study demonstrating widespread synaptic changes in hippocampi of adolescent offspring prenatally exposed to MIA.
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Affiliation(s)
- Magdalena Cieślik
- Department of Cellular Signalling, Mossakowski Medical Research Centre Polish Academy of Sciences, Warsaw, Poland
| | | | - Aleksandra Zawadzka
- Department of Cellular Signalling, Mossakowski Medical Research Centre Polish Academy of Sciences, Warsaw, Poland
| | | | - Magdalena Gewartowska
- Electron Microscopy Platform, Mossakowski Medical Research Centre Polish Academy of Sciences, Warsaw, Poland
| | - Agnieszka Dominiak
- Department of Biochemistry and Pharmacogenomics, Faculty of Pharmacy, Medicine, Medical University of Warsaw, Warsaw, Poland
| | - Grzegorz A Czapski
- Department of Cellular Signalling, Mossakowski Medical Research Centre Polish Academy of Sciences, Warsaw, Poland
| | - Agata Adamczyk
- Department of Cellular Signalling, Mossakowski Medical Research Centre Polish Academy of Sciences, Warsaw, Poland
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15
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Niewiadomska G, Niewiadomski W, Steczkowska M, Gasiorowska A. Tau Oligomers Neurotoxicity. Life (Basel) 2021; 11:28. [PMID: 33418848 PMCID: PMC7824853 DOI: 10.3390/life11010028] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 12/11/2022] Open
Abstract
Although the mechanisms of toxic activity of tau are not fully recognized, it is supposed that the tau toxicity is related rather not to insoluble tau aggregates but to its intermediate forms. It seems that neurofibrillar tangles (NFTs) themselves, despite being composed of toxic tau, are probably neither necessary nor sufficient for tau-induced neuronal dysfunction and toxicity. Tau oligomers (TauOs) formed during the early stages of tau aggregation are the pathological forms that play a key role in eliciting the loss of neurons and behavioral impairments in several neurodegenerative disorders called tauopathies. They can be found in tauopathic diseases, the most common of which is Alzheimer's disease (AD). Evidence of co-occurrence of b-amyloid, α-synuclein, and tau into their most toxic forms, i.e., oligomers, suggests that these species interact and influence each other's aggregation in several tauopathies. The mechanism responsible for oligomeric tau neurotoxicity is a subject of intensive investigation. In this review, we summarize the most recent literature on the damaging effect of TauOs on the stability of the genome and the function of the nucleus, energy production and mitochondrial function, cell signaling and synaptic plasticity, the microtubule assembly, neuronal cytoskeleton and axonal transport, and the effectiveness of the protein degradation system.
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Affiliation(s)
- Grazyna Niewiadomska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland
| | - Wiktor Niewiadomski
- Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland; (W.N.); (M.S.); (A.G.)
| | - Marta Steczkowska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland; (W.N.); (M.S.); (A.G.)
| | - Anna Gasiorowska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland; (W.N.); (M.S.); (A.G.)
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16
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Lemke N, Melis V, Lauer D, Magbagbeolu M, Neumann B, Harrington CR, Riedel G, Wischik CM, Theuring F, Schwab K. Differential compartmental processing and phosphorylation of pathogenic human tau and native mouse tau in the line 66 model of frontotemporal dementia. J Biol Chem 2020; 295:18508-18523. [PMID: 33127647 PMCID: PMC7939472 DOI: 10.1074/jbc.ra120.014890] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 10/09/2020] [Indexed: 12/23/2022] Open
Abstract
Synapse loss is associated with motor and cognitive decline in multiple neurodegenerative disorders, and the cellular redistribution of tau is related to synaptic impairment in tauopathies, such as Alzheimer's disease and frontotemporal dementia. Here, we examined the cellular distribution of tau protein species in human tau overexpressing line 66 mice, a transgenic mouse model akin to genetic variants of frontotemporal dementia. Line 66 mice express intracellular tau aggregates in multiple brain regions and exhibit sensorimotor and motor learning deficiencies. Using a series of anti-tau antibodies, we observed, histologically, that nonphosphorylated transgenic human tau is enriched in synapses, whereas phosphorylated tau accumulates predominantly in cell bodies and axons. Subcellular fractionation confirmed that human tau is highly enriched in insoluble cytosolic and synaptosomal fractions, whereas endogenous mouse tau is virtually absent from synapses. Cytosolic tau was resistant to solubilization with urea and Triton X-100, indicating the formation of larger tau aggregates. By contrast, synaptic tau was partially soluble after Triton X-100 treatment and most likely represents aggregates of smaller size. MS corroborated that synaptosomal tau is nonphosphorylated. Tau enriched in the synapse of line 66 mice, therefore, appears to be in an oligomeric and nonphosphorylated state, and one that could have a direct impact on cognitive function.
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Affiliation(s)
- Nora Lemke
- Charité-Universitätsmedizin Berlin, Berlin, Germany; Bundesanstalt für Materialforschung und-prüfung, Berlin, Germany
| | - Valeria Melis
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | | | | | - Boris Neumann
- Charité-Universitätsmedizin Berlin, Berlin, Germany; Proteome Factory AG, Berlin, Germany
| | - Charles R Harrington
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom; TauRx Therapeutics Ltd., Aberdeen, United Kingdom
| | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Claude M Wischik
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom; TauRx Therapeutics Ltd., Aberdeen, United Kingdom
| | | | - Karima Schwab
- Charité-Universitätsmedizin Berlin, Berlin, Germany.
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17
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Wu Q, Bai Y, Li W, Congdon EE, Liu W, Lin Y, Ji C, Gan WB, Sigurdsson EM. Increased neuronal activity in motor cortex reveals prominent calcium dyshomeostasis in tauopathy mice. Neurobiol Dis 2020; 147:105165. [PMID: 33166699 DOI: 10.1016/j.nbd.2020.105165] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 12/25/2022] Open
Abstract
Perturbed neuronal Ca2+ homeostasis is implicated in Alzheimer's disease, which has primarily been demonstrated in mice with amyloid-β deposits but to a lesser and more variable extent in tauopathy models. In this study, we injected AAV to express Ca2+ indicator in layer II/III motor cortex neurons and measured neuronal Ca2+ activity by two photon imaging in awake transgenic JNPL3 tauopathy and wild-type mice. Various biochemical measurements were conducted in postmortem mouse brains for mechanistic insight and a group of animals received two intravenous injections of a tau monoclonal antibody spaced by four days to test whether the Ca2+ dyshomeostasis was related to pathological tau protein. Under running conditions, we found abnormal neuronal Ca2+ activity in tauopathy mice compared to age-matched wild-type mice with higher frequency of Ca2+ transients, lower amplitude of peak Ca2+ transients and lower total Ca2+ activity in layer II/III motor cortex neurons. While at resting conditions, only Ca2+ frequency was increased. Brain levels of soluble pathological tau correlated better than insoluble tau levels with the degree of Ca2+ dysfunction in tauopathy mice. Furthermore, tau monoclonal antibody 4E6 partially rescued Ca2+ activity abnormalities in tauopathy mice after two intravenous injections and decreased soluble pathological tau protein within the brain. This correlation and antibody effects strongly suggest that the neuronal Ca2+ dyshomeostasis is causally linked to pathological tau protein. These findings also reveal more pronounced neuronal Ca2+ dysregulation in tauopathy mice than previously reported by two-photon imaging that can be partially corrected with an acute tau antibody treatment.
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Affiliation(s)
- Qian Wu
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America.
| | - Yang Bai
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Skirball Institute, 550 First Avenue, New York, NY 10016, United States of America.
| | - Wei Li
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Skirball Institute, 550 First Avenue, New York, NY 10016, United States of America
| | - Erin E Congdon
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America.
| | - Wenke Liu
- New York University Grossman School of Medicine, Department of Psychiatry, 550 First Avenue, New York, NY 10016, United States of America.
| | - Yan Lin
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America.
| | - Changyi Ji
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America.
| | - Wen-Biao Gan
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Skirball Institute, 550 First Avenue, New York, NY 10016, United States of America.
| | - Einar M Sigurdsson
- New York University Grossman School of Medicine, Department of Neuroscience and Physiology, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; New York University Grossman School of Medicine, Neuroscience Institute, Science Building, 435 East 30th Street, New York, NY 10016, United States of America; Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, United States of America.
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18
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Tau and Alpha Synuclein Synergistic Effect in Neurodegenerative Diseases: When the Periphery Is the Core. Int J Mol Sci 2020; 21:ijms21145030. [PMID: 32708732 PMCID: PMC7404325 DOI: 10.3390/ijms21145030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 02/08/2023] Open
Abstract
In neuronal cells, tau is a microtubule-associated protein placed in axons and alpha synuclein is enriched at presynaptic terminals. They display a propensity to form pathologic aggregates, which are considered the underlying cause of Alzheimer's and Parkinson's diseases. Their functional impairment induces loss of axonal transport, synaptic and mitochondrial disarray, leading to a "dying back" pattern of degeneration, which starts at the periphery of cells. In addition, pathologic spreading of alpha-synuclein from the peripheral nervous system to the brain through anatomical connectivity has been demonstrated for Parkinson's disease. Thus, examination of the extent and types of tau and alpha-synuclein in peripheral tissues and their relation to brain neurodegenerative diseases is of relevance since it may provide insights into patterns of protein aggregation and neurodegeneration. Moreover, peripheral nervous tissues are easily accessible in-vivo and can play a relevant role in the early diagnosis of these conditions. Up-to-date investigations of tau species in peripheral tissues are scant and have mainly been restricted to rodents, whereas, more evidence is available on alpha synuclein in peripheral tissues. Here we aim to review the literature on the functional role of tau and alpha synuclein in physiological conditions and disease at the axonal level, their distribution in peripheral tissues, and discuss possible commonalities/diversities as well as their interaction in proteinopathies.
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19
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Liquid-liquid phase separation induces pathogenic tau conformations in vitro. Nat Commun 2020; 11:2809. [PMID: 32499559 PMCID: PMC7272632 DOI: 10.1038/s41467-020-16580-3] [Citation(s) in RCA: 143] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/08/2020] [Indexed: 01/21/2023] Open
Abstract
Formation of membrane-less organelles via liquid-liquid phase separation is one way cells meet the biological requirement for spatiotemporal regulation of cellular components and reactions. Recently, tau, a protein known for its involvement in Alzheimer’s disease and other tauopathies, was found to undergo liquid–liquid phase separation making it one of several proteins associated with neurodegenerative diseases to do so. Here, we demonstrate that tau forms dynamic liquid droplets in vitro at physiological protein levels upon molecular crowding in buffers that resemble physiological conditions. Tau droplet formation is significantly enhanced by disease-associated modifications, including the AT8 phospho-epitope and the P301L tau mutation linked to an inherited tauopathy. Moreover, tau droplet dynamics are significantly reduced by these modified forms of tau. Extended phase separation promoted a time-dependent adoption of toxic conformations and oligomerization, but not filamentous aggregation. P301L tau protein showed the greatest oligomer formation following extended phase separation. These findings suggest that phase separation of tau may facilitate the formation of non-filamentous pathogenic tau conformations. Tau plays an important role in tauopathies and undergoes liquid-liquid phase separation (LLPS). The authors show that disease-related P301L mutant and phosphomimic (S199E/S202E/T205E) tau enhance LLPS in vitro at physiological levels, and using specific antibodies, that tau LLPS leads to pathological conformations such as N-terminal exposure and oligomeric species.
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20
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Transgenic Mice Overexpressing Human STIM2 and ORAI1 in Neurons Exhibit Changes in Behavior and Calcium Homeostasis but Show No Signs of Neurodegeneration. Int J Mol Sci 2020; 21:ijms21030842. [PMID: 32012922 PMCID: PMC7037127 DOI: 10.3390/ijms21030842] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/23/2020] [Accepted: 01/26/2020] [Indexed: 01/10/2023] Open
Abstract
The maintenance of proper cytosolic Ca2+ level is crucial for neuronal survival, and dysregulation of Ca2+ homeostasis is found in a variety of neurological disorders, including Alzheimer’s disease. According to the “Ca2+ hypothesis of aging”, Ca2+ disturbances precede the onset of AD symptoms and lead to neurodegeneration. STIM and ORAI proteins are involved in neuronal physiological and pathological processes as essential components of the store-operated Ca2+ entry. Our previous data suggested that overexpression of STIM2 and ORAI1 might increase basal neuronal cytosolic Ca2+ level. We generated double transgenic mice overexpressing these two genes in neurons, expecting that the increased basal Ca2+ concentration will lead to premature neurodegeneration. We observed changes in Ca2+ homeostasis and electrophysiological properties in acute brain slices of STIM2/ORAI1 neurons. However, we did not observe any augmentation of neurodegenerative processes, as tested by Fluoro-Jade® C staining and assessment of amyloidogenesis. The battery of behavioral tests did not show any signs of accelerated aging. We conclude that changes of calcium homeostasis induced by overexpression of STIM2 and ORAI1 had no substantial adverse effects on neurons and did not lead to early neurodegeneration.
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21
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Amadoro G, Latina V, Corsetti V, Calissano P. N-terminal tau truncation in the pathogenesis of Alzheimer's disease (AD): Developing a novel diagnostic and therapeutic approach. Biochim Biophys Acta Mol Basis Dis 2019; 1866:165584. [PMID: 31676377 DOI: 10.1016/j.bbadis.2019.165584] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/23/2019] [Accepted: 09/24/2019] [Indexed: 01/04/2023]
Abstract
Tau truncation occurs at early stages during the development of human Alzheimer's disease (AD) and other tauopathy dementias. Tau cleavage, particularly in its N-terminal projection domain, is able to drive per se neurodegeneration, regardless of its pro-aggregative pathway(s) and in fragment(s)-dependent way. In this short review, we highlight the pathological relevance of the 20-22 kDa NH2-truncated tau fragment which is endowed with potent neurotoxic "gain-of-function" action(s), both in vitro and in vivo. An extensive comment on its clinical value as novel progression/diagnostic biomarker and potential therapeutic target in the context of tau-mediated neurodegeneration is also provided.
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Affiliation(s)
- G Amadoro
- European Brain Research Institute (EBRI), Viale Regina Elena 295, 00161 Rome, Italy; Institute of Translational Pharmacology (IFT)-CNR, Via Fosso del Cavaliere 100, 00133 Rome, Italy.
| | - V Latina
- European Brain Research Institute (EBRI), Viale Regina Elena 295, 00161 Rome, Italy
| | - V Corsetti
- European Brain Research Institute (EBRI), Viale Regina Elena 295, 00161 Rome, Italy
| | - P Calissano
- European Brain Research Institute (EBRI), Viale Regina Elena 295, 00161 Rome, Italy
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22
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Paudel YN, Angelopoulou E, Jones NC, O’Brien TJ, Kwan P, Piperi C, Othman I, Shaikh MF. Tau Related Pathways as a Connecting Link between Epilepsy and Alzheimer's Disease. ACS Chem Neurosci 2019; 10:4199-4212. [PMID: 31532186 DOI: 10.1021/acschemneuro.9b00460] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Emerging findings point toward an important interconnection between epilepsy and Alzheimer's disease (AD) pathogenesis. Patients with epilepsy (PWE) commonly exhibit cognitive impairment similar to AD patients, who in turn are at a higher risk of developing epilepsy compared to age-matched controls. To date, no disease-modifying treatment strategy is available for either epilepsy or AD, reflecting an immediate need for exploring common molecular targets, which can delineate a possible mechanistic link between epilepsy and AD. This review attempts to disentangle the interconnectivity between epilepsy and AD pathogenesis via the crucial contribution of Tau protein. Tau protein is a microtubule-associated protein (MAP) that has been implicated in the pathophysiology of both epilepsy and AD. Hyperphosphorylation of Tau contributes to the different forms of human epilepsy and inhibition of the same exerted seizure inhibitions and altered disease progression in a range of animal models. Moreover, Tau-protein-mediated therapy has demonstrated promising outcomes in experimental models of AD. In this review, we discuss how Tau-related mechanisms might present a link between the cause of seizures in epilepsy and cognitive disruption in AD. Untangling this interconnection might be instrumental in designing novel therapies that can minimize epileptic seizures and cognitive deficits in patients with epilepsy and AD.
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Affiliation(s)
- Yam Nath Paudel
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 46150, Malaysia
| | - Efthalia Angelopoulou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, Athens 10679, Greece
| | - Nigel C. Jones
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
| | - Terence J. O’Brien
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
| | - Patrick Kwan
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
| | - Christina Piperi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, Athens 10679, Greece
| | - Iekhsan Othman
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 46150, Malaysia
| | - Mohd. Farooq Shaikh
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 46150, Malaysia
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
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23
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Introduction of Tau Oligomers into Cortical Neurons Alters Action Potential Dynamics and Disrupts Synaptic Transmission and Plasticity. eNeuro 2019; 6:ENEURO.0166-19.2019. [PMID: 31554666 PMCID: PMC6794083 DOI: 10.1523/eneuro.0166-19.2019] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 08/29/2019] [Accepted: 09/12/2019] [Indexed: 01/08/2023] Open
Abstract
Tau is a highly soluble microtubule-associated protein that acts within neurons to modify microtubule stability. However, abnormally phosphorylated tau dissociates from microtubules to form oligomers and fibrils which associate in the somatodendritic compartment. Although tau can form neurofibrillary tangles (NFTs), it is the soluble oligomers that appear to be the toxic species. There is, however, relatively little quantitative information on the concentration-dependent and time-dependent actions of soluble tau oligomers (oTau) on the electrophysiological and synaptic properties of neurons. Here, whole-cell patch clamp recording was used to introduce known concentrations of oligomeric full-length tau-441 into mouse hippocampal CA1 pyramidal and neocortical Layer V thick-tufted pyramidal cells. oTau increased input resistance, reduced action potential amplitude and slowed action potential rise and decay kinetics. oTau injected into presynaptic neurons induced the run-down of unitary EPSPs which was associated with increased short-term depression. In contrast, introduction of oTau into postsynaptic neurons had no effect on basal synaptic transmission, but markedly impaired the induction of long-term potentiation (LTP). Consistent with its effects on synaptic transmission and plasticity, oTau puncta could be observed in the soma, axon and in the distal dendrites of injected neurons.
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24
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Bexarotene therapy ameliorates behavioral deficits and induces functional and molecular changes in very-old Triple Transgenic Mice model of Alzheimer´s disease. PLoS One 2019; 14:e0223578. [PMID: 31596896 PMCID: PMC6785083 DOI: 10.1371/journal.pone.0223578] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 09/24/2019] [Indexed: 12/11/2022] Open
Abstract
Introduction Bexarotene, a retinoid X receptor agonist, improves cognition in murine models of Alzheimer’s disease (AD). This study evaluated the effects of bexarotene on pathological and electrophysiological changes in very old triple transgenic AD mice (3xTg-AD mice). Methods 24-month-old 3xTg-AD mice were treated with bexarotene (100 mg/kg/day for 30 days). The Morris water maze was used to evaluate spatial memory; immunofluorescence and confocal microscopy were used to evaluate pathological changes; and in vivo electrophysiological recordings were used to evaluate basal transmission and plasticity in the commissural CA3-CA1 pathway. Results In addition to cognitive improvement, bexarotene-treated 3xTg-AD mice were found to have 1) reductions of astrogliosis and reactive microglia both in cortex and hippocampus; 2) increased ApoE expression restricted to CA1; 3) increased number of cells co-labeled with ApoE and NeuN; 4) recovery of NeuN expression, suggesting neuronal protection; and, 5) recovery of basal synaptic transmission and synaptic plasticity. Discussion These results indicate that bexarotene-induced improvement in cognition is due to multiple changes that contribute to recovery of synaptic plasticity.
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25
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Zamponi E, Pigino GF. Protein Misfolding, Signaling Abnormalities and Altered Fast Axonal Transport: Implications for Alzheimer and Prion Diseases. Front Cell Neurosci 2019; 13:350. [PMID: 31417367 PMCID: PMC6683957 DOI: 10.3389/fncel.2019.00350] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 07/15/2019] [Indexed: 12/21/2022] Open
Abstract
Histopathological studies revealed that progressive neuropathies including Alzheimer, and Prion diseases among others, include accumulations of misfolded proteins intracellularly, extracellularly, or both. Experimental evidence suggests that among the accumulated misfolded proteins, small soluble oligomeric conformers represent the most neurotoxic species. Concomitant phenomena shared by different protein misfolding diseases includes alterations in phosphorylation-based signaling pathways synaptic dysfunction, and axonal pathology, but mechanisms linking these pathogenic features to aggregated neuropathogenic proteins remain unknown. Relevant to this issue, results from recent work revealed inhibition of fast axonal transport (AT) as a novel toxic effect elicited by oligomeric forms of amyloid beta and cellular prion protein PrPC, signature pathological proteins associated with Alzheimer and Prion diseases, respectively. Interestingly, the toxic effect of these oligomers was fully prevented by pharmacological inhibitors of casein kinase 2 (CK2), a remarkable discovery with major implications for the development of pharmacological target-driven therapeutic intervention for Alzheimer and Prion diseases.
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Affiliation(s)
- Emiliano Zamponi
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, United States
| | - Gustavo F Pigino
- Laboratorio de Neuropatología Experimental, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
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26
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Berrocal M, Caballero-Bermejo M, Gutierrez-Merino C, Mata AM. Methylene Blue Blocks and Reverses the Inhibitory Effect of Tau on PMCA Function. Int J Mol Sci 2019; 20:ijms20143521. [PMID: 31323781 PMCID: PMC6678728 DOI: 10.3390/ijms20143521] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/05/2019] [Accepted: 07/11/2019] [Indexed: 12/24/2022] Open
Abstract
Methylene blue (MB) is a synthetic phenothiazine dye that, in the last years, has generated much debate about whether it could be a useful therapeutic drug for tau-related pathologies, such as Alzheimer’s disease (AD). However, the molecular mechanism of action is far from clear. Recently we reported that MB activates the plasma membrane Ca2+-ATPase (PMCA) in membranes from human and pig tissues and from cells cultures, and that it could protect against inactivation of PMCA by amyloid β-peptide (Aβ). The purpose of the present study is to further examine whether the MB could also modulate the inhibitory effect of tau, another key molecular marker of AD, on PMCA activity. By using kinetic assays in membranes from several tissues and cell cultures, we found that this phenothiazine was able to block and even to completely reverse the inhibitory effect of tau on PMCA. The results of this work point out that MB could mediate the toxic effect of tau related to the deregulation of calcium homeostasis by blocking the impairment of PMCA activity by tau. We then could conclude that MB could interfere with the toxic effects of tau by restoring the function of PMCA pump as a fine tuner of calcium homeostasis.
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Affiliation(s)
- Maria Berrocal
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Montaña Caballero-Bermejo
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Carlos Gutierrez-Merino
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Ana M Mata
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain.
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27
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Abstract
Tau protein, which was discovered in Prof. Kirschner's laboratory in 1975, has been the focus of my research over the last 40 years. In this issue of the Journal of Alzheimer's Disease commemorating its 20th year of publication, I will provide a short review of some of the features of my relationship with tau.
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Affiliation(s)
- Jesús Avila
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain.,CIBERNED, Madrid, Spain
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28
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Ondrejcak T, Hu NW, Qi Y, Klyubin I, Corbett GT, Fraser G, Perkinton MS, Walsh DM, Billinton A, Rowan MJ. Soluble tau aggregates inhibit synaptic long-term depression and amyloid β-facilitated LTD in vivo. Neurobiol Dis 2019; 127:582-590. [PMID: 30910746 DOI: 10.1016/j.nbd.2019.03.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/01/2019] [Accepted: 03/21/2019] [Indexed: 01/29/2023] Open
Abstract
Soluble synaptotoxic aggregates of the main pathological proteins of Alzheimer's disease, amyloid β-protein (Aß) and tau, have rapid and potent inhibitory effects on long-term potentiation (LTP). Although the promotion of synaptic weakening mechanisms, including long-term depression (LTD), is posited to mediate LTP inhibition by Aß, little is known regarding the action of exogenous tau on LTD. The present study examined the ability of different assemblies of full-length human tau to affect LTD in the dorsal hippocampus of the anaesthetized rat. Unlike Aß, intracerebroventricular injection of soluble aggregates of tau (SτAs), but not monomers or fibrils, potently increased the threshold for LTD induction in a manner that required cellular prion protein. However, MTEP, an antagonist of the putative prion protein coreceptor metabotropic glutamate receptor 5, did not prevent the disruption of synaptic plasticity by SτAs. In contrast, systemic treatment with Ro 25-6981, a selective antagonist at GluN2B subunit-containing NMDA receptors, reduced SτA-mediated inhibition of LTD, but not LTP. Intriguingly, SτAs completely blocked Aß-facilitated LTD, whereas a subthreshold dose of SτAs facilitated Aß-mediated inhibition of LTP. Overall, these findings support the importance of cellular prion protein in mediating a range of, sometimes opposing, actions of soluble Aß and tau aggregates with different effector mechanisms on synaptic plasticity.
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Affiliation(s)
- Tomas Ondrejcak
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
| | - Neng-Wei Hu
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland; Department of Physiology and Neurobiology, Zhengzhou University School of Medicine, Zhengzhou 450001, China
| | - Yingjie Qi
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Igor Klyubin
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Grant T Corbett
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Graham Fraser
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge CB21 6GH, UK
| | | | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Andrew Billinton
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge CB21 6GH, UK
| | - Michael J Rowan
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
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29
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Mendelsohn AR, Larrick JW. Cellular Senescence as the Key Intermediate in Tau-Mediated Neurodegeneration. Rejuvenation Res 2019; 21:572-579. [PMID: 30489222 DOI: 10.1089/rej.2018.2155] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Neuroinflammation is thought to play a key role in the progression of neurodegenerative disease such as Alzheimer's disease (AD). Given the apparent nexus of inflammatory disease with the secretory-associated senescence phenotype (SASP) of cellular senescence, two reports found that tau-mediated neurodegeneration involves induction of senescence in astrocytes, microglia, and possibly even neurons. Elimination of senescent cells by pharmacologically induced genetic ablation or by senolytic drugs blocks progression of mutant human tau-mediated neurodegeneration in mice. This work suggests a working hypothesis through which tau activation leads to senescence and then tau propagation throughout the brain is supported by, and neurotoxicity is caused by, SASP, forming a pathological positive feedback loop. Although preliminary, these data suggest that the development of senolytics for AD and other tauopathies, especially early disease, and possibly senomodulatory drugs for later stage neurodegenerative disease may prove fruitful.
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Affiliation(s)
- Andrew R Mendelsohn
- 1 Panorama Research Institute, Sunnyvale, California.,2 Regenerative Sciences Institute, Sunnyvale, California
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30
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Combs B, Mueller RL, Morfini G, Brady ST, Kanaan NM. Tau and Axonal Transport Misregulation in Tauopathies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1184:81-95. [PMID: 32096030 DOI: 10.1007/978-981-32-9358-8_7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Tau is a microtubule-associated protein that is involved in both normal and pathological processes in neurons. Since the discovery and characterization of tau over 40 years ago, our understanding of tau's normal functions and toxic roles in neurodegenerative tauopathies has continued to expand. Fast axonal transport is a critical process for maintaining axons and functioning synapses, critical subcellular compartments underlying neuronal connectivity. Signs of fast axonal transport disruption are pervasive in Alzheimer's disease and other tauopathies and various mechanisms have been proposed for regulation of fast axonal transport by tau. Post-translational modifications of tau including phosphorylation at specific sites, FTDP-17 point mutations, and oligomerization, confer upon tau a toxic effect on fast axonal transport. Consistent with the well-established dependence of axons on fast axonal transport, these disease-related modifications are closely associated temporally and spatially with axonal degeneration in the early disease stages. These factors position tau as a potentially critical factor mediating the disruption of fast axonal transport that precedes synaptic dysfunction and axonal degeneration at later disease stages. In this chapter, we review the evidence that tau affects fast axonal transport and examine several potential mechanisms proposed to underlie this toxicity.
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Affiliation(s)
- Benjamin Combs
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA
| | - Rebecca L Mueller
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA.,Neuroscience Program, Michigan State University, East Lansing, MI, USA
| | - Gerardo Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA.,Marine Biological Laboratory, Woods Hole, MA, USA
| | - Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA.,Marine Biological Laboratory, Woods Hole, MA, USA
| | - Nicholas M Kanaan
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA. .,Neuroscience Program, Michigan State University, East Lansing, MI, USA. .,Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, MI, USA.
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31
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Kuznetsov IA, Kuznetsov AV. Investigating sensitivity coefficients characterizing the response of a model of tau protein transport in an axon to model parameters. Comput Methods Biomech Biomed Engin 2018; 22:71-83. [PMID: 30580604 DOI: 10.1080/10255842.2018.1534233] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Evaluating the sensitivity of biological models to various model parameters is a critical step towards advancing our understanding of biological systems. In this paper, we investigated sensitivity coefficients for a model simulating transport of tau protein along the axon. This is an important problem due to the relevance of tau transport and agglomeration to Alzheimer's disease and other tauopathies, such as some forms of parkinsonism. The sensitivity coefficients that we obtained characterize how strongly three observables (the tau concentration, average tau velocity, and the percentage of tau bound to microtubules) depend on model parameters. The fact that the observables strongly depend on a parameter characterizing tau transition from the retrograde to the anterograde kinetic states suggests the importance of motor-driven transport of tau. The observables are sensitive to kinetic constants characterizing tau concentration in the free (cytosolic) state only at small distances from the soma. Cytosolic tau can only be transported by diffusion, suggesting that diffusion-driven transport of tau only plays a role in the proximal axon. Our analysis also shows the location in the axon in which an observable has the greatest sensitivity to a certain parameter. For most parameters, this location is in the proximal axon. This could be useful for designing an experiment aimed at determining the value of this parameter. We also analyzed sensitivity of the average tau velocity, the total tau concentration, and the percentage of microtubule-bound tau to cytosolic diffusivity of tau and diffusivity of bound tau along the MT lattice. The model predicts that at small distances from the soma the effect of these two diffusion processes is comparable.
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Affiliation(s)
- Ivan A Kuznetsov
- a Perelman School of Medicine , University of Pennsylvania , Philadelphia , PA , USA.,b Department of Bioengineering , University of Pennsylvania , Philadelphia , PA , USA
| | - Andrey V Kuznetsov
- c Department of Mechanical and Aerospace Engineering , North Carolina State University , Raleigh , NC , USA
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32
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Chen Y, Fu AKY, Ip NY. Synaptic dysfunction in Alzheimer's disease: Mechanisms and therapeutic strategies. Pharmacol Ther 2018; 195:186-198. [PMID: 30439458 DOI: 10.1016/j.pharmthera.2018.11.006] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease (AD), the most prevalent neurodegenerative disease in the elderly population, is characterized by progressive cognitive decline and pathological hallmarks of amyloid plaques and neurofibrillary tangles. However, its pathophysiological mechanisms are poorly understood, and diagnostic tools and interventions are limited. Here, we review recent research on the amyloid hypothesis and beta-amyloid-induced dysfunction of neuronal synapses through distinct cell surface receptors. We also review how tau protein leads to synaptotoxicity through pathological modification, localization, and propagation. Finally, we discuss experimental therapeutics for AD and propose potential applications of disease-modifying strategies targeting synaptic failure for improved treatment of AD.
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Affiliation(s)
- Yu Chen
- Division of Life Science, State Key Laboratory of Molecular Neuroscience and Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; The Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, HKUST Shenzhen Research Institute, Shenzhen, Guangdong, China.
| | - Amy K Y Fu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience and Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, HKUST Shenzhen Research Institute, Shenzhen, Guangdong, China
| | - Nancy Y Ip
- Division of Life Science, State Key Laboratory of Molecular Neuroscience and Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, HKUST Shenzhen Research Institute, Shenzhen, Guangdong, China.
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33
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The Transcriptional Regulatory Properties of Amyloid Beta 1–42 may Include Regulation of Genes Related to Neurodegeneration. Neuromolecular Med 2018; 20:363-375. [DOI: 10.1007/s12017-018-8498-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/09/2018] [Indexed: 12/19/2022]
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34
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Giannopoulos PF, Chiu J, Praticò D. Learning Impairments, Memory Deficits, and Neuropathology in Aged Tau Transgenic Mice Are Dependent on Leukotrienes Biosynthesis: Role of the cdk5 Kinase Pathway. Mol Neurobiol 2018; 56:1211-1220. [PMID: 29881943 DOI: 10.1007/s12035-018-1124-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/11/2018] [Indexed: 01/21/2023]
Abstract
Previous studies showed that the leukotrienes pathway is increased in human tauopathy and that its manipulation may modulate the onset and development of the pathological phenotype of tau transgenic mice. However, whether interfering with leukotrienes biosynthesis is beneficial after the behavioral deficits and the neuropathology have fully developed in these mice is not known. To test this hypothesis, aged tau transgenic mice were randomized to receive zileuton, a specific leukotriene biosynthesis inhibitor, or vehicle starting at 12 months of age for 16 weeks and then assessed in their functional and pathological phenotype. Compared with baseline, we observed that untreated tau mice had a worsening of their memory and spatial learning. By contrast, tau mice treated with zileuton had a reversal of these deficits and behaved in an undistinguishable manner from wild-type mice. Leukotriene-inhibited tau mice had an amelioration of synaptic integrity, lower levels of neuroinflammation, and a significant reduction in tau phosphorylation and pathology, which was secondary to an involvement of the cdk5 kinase pathway. Taken together, our findings represent the first demonstration that the leukotriene biosynthesis is functionally involved at the later stages of the tau pathological phenotype and represents an ideal target with viable therapeutic potential for treating human tauopathies.
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Affiliation(s)
- Phillip F Giannopoulos
- Alzheimer's Center at Temple, Lewis Katz School of Medicine, Scott Richards North Star Foundation Chair, Alzheimer's Research, Temple University, 947, Medical Education and Research Building, 3500 North Broad Street, Philadelphia, PA, 19140, USA
| | - Jian Chiu
- Alzheimer's Center at Temple, Lewis Katz School of Medicine, Scott Richards North Star Foundation Chair, Alzheimer's Research, Temple University, 947, Medical Education and Research Building, 3500 North Broad Street, Philadelphia, PA, 19140, USA
| | - Domenico Praticò
- Alzheimer's Center at Temple, Lewis Katz School of Medicine, Scott Richards North Star Foundation Chair, Alzheimer's Research, Temple University, 947, Medical Education and Research Building, 3500 North Broad Street, Philadelphia, PA, 19140, USA.
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35
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Giannopoulos PF, Chiu J, Praticò D. Antileukotriene therapy by reducing tau phosphorylation improves synaptic integrity and cognition of P301S transgenic mice. Aging Cell 2018; 17:e12759. [PMID: 29607621 PMCID: PMC5946065 DOI: 10.1111/acel.12759] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2018] [Indexed: 12/15/2022] Open
Abstract
The 5‐lipoxygenase (5LO) is a source of inflammatory leukotrienes and is upregulated in Alzheimer's disease and related tauopathies. However, whether it directly modulates tau phosphorylation and the development of its typical neuropathology in the absence of Aβ or is a secondary event during the course of the disease pathogenesis remains to be fully elucidated. The goal of this study was to evaluate the effect that pharmacologic blockade of this inflammatory pathway has on the phenotype of a transgenic mouse model of tauopathy, the P301S mice. Starting at 3 months of age, P301S mice were randomized to receive zileuton, a specific 5LO blocker, for 7 months; then, its effect on their behavioral deficits and neuropathology was assessed. Inhibition of leukotrienes formation was associated with a reduction in tau phosphorylation and an amelioration of memory and learning as well as synaptic integrity, which were secondary to a downregulation of the cdk5 kinase pathway. Our results demonstrate that the 5LO enzyme is a key player in modulating tau phosphorylation and pathology and that blockade of its enzymatic activity represents a desirable disease‐modifying therapeutic approach for tauopathy.
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Affiliation(s)
- Phillip F. Giannopoulos
- Alzheimer's Center at Temple; Lewis Katz Temple University School of Medicine; Philadelphia PA USA
| | - Jian Chiu
- Alzheimer's Center at Temple; Lewis Katz Temple University School of Medicine; Philadelphia PA USA
| | - Domenico Praticò
- Alzheimer's Center at Temple; Lewis Katz Temple University School of Medicine; Philadelphia PA USA
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36
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Sánchez MP, García-Cabrero AM, Sánchez-Elexpuru G, Burgos DF, Serratosa JM. Tau-Induced Pathology in Epilepsy and Dementia: Notions from Patients and Animal Models. Int J Mol Sci 2018; 19:ijms19041092. [PMID: 29621183 PMCID: PMC5979593 DOI: 10.3390/ijms19041092] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 03/23/2018] [Accepted: 04/03/2018] [Indexed: 12/24/2022] Open
Abstract
Patients with dementia present epilepsy more frequently than the general population. Seizures are more common in patients with Alzheimer’s disease (AD), dementia with Lewy bodies (LBD), frontotemporal dementia (FTD) and progressive supranuclear palsy (PSP) than in other dementias. Missense mutations in the microtubule associated protein tau (MAPT) gene have been found to cause familial FTD and PSP, while the P301S mutation in MAPT has been associated with early-onset fast progressive dementia and the presence of seizures. Brains of patients with AD, LBD, FTD and PSP show hyperphosphorylated tau aggregates, amyloid-β plaques and neuropil threads. Increasing evidence suggests the existence of overlapping mechanisms related to the generation of network hyperexcitability and cognitive decline. Neuronal overexpression of tau with various mutations found in FTD with parkinsonism-linked to chromosome 17 (FTDP-17) in mice produces epileptic activity. On the other hand, the use of certain antiepileptic drugs in animal models with AD prevents cognitive impairment. Further efforts should be made to search for plausible common targets for both conditions. Moreover, attempts should also be made to evaluate the use of drugs targeting tau and amyloid-β as suitable pharmacological interventions in epileptic disorders. The diagnosis of dementia and epilepsy in early stages of those diseases may be helpful for the initiation of treatments that could prevent the generation of epileptic activity and cognitive deterioration.
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Affiliation(s)
- Marina P Sánchez
- Laboratory of Neurology, IIS (Instituto Investigación Sanitaria/Health Research Institute)-Jiménez Díaz Foundation, UAM (Universidad Autonoma de Madrid/Autonomous University of Madrid) and Biomedical Research Network Center on Rare Diseases (CIBERER), 28045 Madrid, Spain.
| | - Ana M García-Cabrero
- Laboratory of Neurology, IIS (Instituto Investigación Sanitaria/Health Research Institute)-Jiménez Díaz Foundation, UAM (Universidad Autonoma de Madrid/Autonomous University of Madrid) and Biomedical Research Network Center on Rare Diseases (CIBERER), 28045 Madrid, Spain.
- Department of Immunology and Oncology and Protein Tools Unit, Biotechnology National Center (CNB/CSIC), 28049 Madrid, Spain.
| | - Gentzane Sánchez-Elexpuru
- Laboratory of Neurology, IIS (Instituto Investigación Sanitaria/Health Research Institute)-Jiménez Díaz Foundation, UAM (Universidad Autonoma de Madrid/Autonomous University of Madrid) and Biomedical Research Network Center on Rare Diseases (CIBERER), 28045 Madrid, Spain.
| | - Daniel F Burgos
- Laboratory of Neurology, IIS (Instituto Investigación Sanitaria/Health Research Institute)-Jiménez Díaz Foundation, UAM (Universidad Autonoma de Madrid/Autonomous University of Madrid) and Biomedical Research Network Center on Rare Diseases (CIBERER), 28045 Madrid, Spain.
| | - José M Serratosa
- Laboratory of Neurology, IIS (Instituto Investigación Sanitaria/Health Research Institute)-Jiménez Díaz Foundation, UAM (Universidad Autonoma de Madrid/Autonomous University of Madrid) and Biomedical Research Network Center on Rare Diseases (CIBERER), 28045 Madrid, Spain.
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37
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AD-Related N-Terminal Truncated Tau Is Sufficient to Recapitulate In Vivo the Early Perturbations of Human Neuropathology: Implications for Immunotherapy. Mol Neurobiol 2018; 55:8124-8153. [PMID: 29508283 DOI: 10.1007/s12035-018-0974-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 02/19/2018] [Indexed: 01/08/2023]
Abstract
The NH2tau 26-44 aa (i.e., NH2htau) is the minimal biologically active moiety of longer 20-22-kDa NH2-truncated form of human tau-a neurotoxic fragment mapping between 26 and 230 amino acids of full-length protein (htau40)-which is detectable in presynaptic terminals and peripheral CSF from patients suffering from AD and other non-AD neurodegenerative diseases. Nevertheless, whether its exogenous administration in healthy nontransgenic mice is able to elicit a neuropathological phenotype resembling human tauopathies has not been yet investigated. We explored the in vivo effects evoked by subchronic intracerebroventricular (i.c.v.) infusion of NH2htau or its reverse counterpart into two lines of young (2-month-old) wild-type mice (C57BL/6 and B6SJL). Six days after its accumulation into hippocampal parenchyma, significant impairment in memory/learning performance was detected in NH2htau-treated group in association with reduced synaptic connectivity and neuroinflammatory response. Compromised short-term plasticity in paired-pulse facilitation paradigm (PPF) was detected in the CA3/CA1 synapses from NH2htau-impaired animals along with downregulation in calcineurin (CaN)-stimulated pCREB/c-Fos pathway(s). Importantly, these behavioral, synaptotoxic, and neuropathological effects were independent from the genetic background, occurred prior to frank neuronal loss, and were specific because no alterations were detected in the control group infused with its reverse counterpart. Finally, a 2.0-kDa peptide which biochemically and immunologically resembles the injected NH2htau was endogenously detected in vivo, being present in hippocampal synaptosomal preparations from AD subjects. Given that the identification of the neurotoxic tau species is mandatory to develop a more effective tau-based immunological approach, our evidence can have important translational implications for cure of human tauopathies.
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38
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Prion protein inhibits fast axonal transport through a mechanism involving casein kinase 2. PLoS One 2017; 12:e0188340. [PMID: 29261664 PMCID: PMC5737884 DOI: 10.1371/journal.pone.0188340] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 11/06/2017] [Indexed: 12/13/2022] Open
Abstract
Prion diseases include a number of progressive neuropathies involving conformational changes in cellular prion protein (PrPc) that may be fatal sporadic, familial or infectious. Pathological evidence indicated that neurons affected in prion diseases follow a dying-back pattern of degeneration. However, specific cellular processes affected by PrPc that explain such a pattern have not yet been identified. Results from cell biological and pharmacological experiments in isolated squid axoplasm and primary cultured neurons reveal inhibition of fast axonal transport (FAT) as a novel toxic effect elicited by PrPc. Pharmacological, biochemical and cell biological experiments further indicate this toxic effect involves casein kinase 2 (CK2) activation, providing a molecular basis for the toxic effect of PrPc on FAT. CK2 was found to phosphorylate and inhibit light chain subunits of the major motor protein conventional kinesin. Collectively, these findings suggest CK2 as a novel therapeutic target to prevent the gradual loss of neuronal connectivity that characterizes prion diseases.
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39
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Kneynsberg A, Combs B, Christensen K, Morfini G, Kanaan NM. Axonal Degeneration in Tauopathies: Disease Relevance and Underlying Mechanisms. Front Neurosci 2017; 11:572. [PMID: 29089864 PMCID: PMC5651019 DOI: 10.3389/fnins.2017.00572] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 09/29/2017] [Indexed: 12/14/2022] Open
Abstract
Tauopathies are a diverse group of diseases featuring progressive dying-back neurodegeneration of specific neuronal populations in association with accumulation of abnormal forms of the microtubule-associated protein tau. It is well-established that the clinical symptoms characteristic of tauopathies correlate with deficits in synaptic function and neuritic connectivity early in the course of disease, but mechanisms underlying these critical pathogenic events are not fully understood. Biochemical in vitro evidence fueled the widespread notion that microtubule stabilization represents tau's primary biological role and that the marked atrophy of neurites observed in tauopathies results from loss of microtubule stability. However, this notion contrasts with the mild phenotype associated with tau deletion. Instead, an analysis of cellular hallmarks common to different tauopathies, including aberrant patterns of protein phosphorylation and early degeneration of axons, suggests that alterations in kinase-based signaling pathways and deficits in axonal transport (AT) associated with such alterations contribute to the loss of neuronal connectivity triggered by pathogenic forms of tau. Here, we review a body of literature providing evidence that axonal pathology represents an early and common pathogenic event among human tauopathies. Observations of axonal degeneration in animal models of specific tauopathies are discussed and similarities to human disease highlighted. Finally, we discuss potential mechanistic pathways other than microtubule destabilization by which disease-related forms of tau may promote axonopathy.
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Affiliation(s)
- Andrew Kneynsberg
- Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Benjamin Combs
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Kyle Christensen
- Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Gerardo Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Nicholas M Kanaan
- Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States.,Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, MI, United States
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40
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Florenzano F, Veronica C, Ciasca G, Ciotti MT, Pittaluga A, Olivero G, Feligioni M, Iannuzzi F, Latina V, Maria Sciacca MF, Sinopoli A, Milardi D, Pappalardo G, Marco DS, Papi M, Atlante A, Bobba A, Borreca A, Calissano P, Amadoro G. Extracellular truncated tau causes early presynaptic dysfunction associated with Alzheimer's disease and other tauopathies. Oncotarget 2017; 8:64745-64778. [PMID: 29029390 PMCID: PMC5630290 DOI: 10.18632/oncotarget.17371] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/11/2017] [Indexed: 12/14/2022] Open
Abstract
The largest part of tau secreted from AD nerve terminals and released in cerebral spinal fluid (CSF) is C-terminally truncated, soluble and unaggregated supporting potential extracellular role(s) of NH2 -derived fragments of protein on synaptic dysfunction underlying neurodegenerative tauopathies, including Alzheimer's disease (AD). Here we show that sub-toxic doses of extracellular-applied human NH2 tau 26-44 (aka NH 2 htau) -which is the minimal active moiety of neurotoxic 20-22kDa peptide accumulating in vivo at AD synapses and secreted into parenchyma- acutely provokes presynaptic deficit in K+ -evoked glutamate release on hippocampal synaptosomes along with alteration in local Ca2+ dynamics. Neuritic dystrophy, microtubules breakdown, deregulation in presynaptic proteins and loss of mitochondria located at nerve endings are detected in hippocampal cultures only after prolonged exposure to NH 2 htau. The specificity of these biological effects is supported by the lack of any significant change, either on neuronal activity or on cellular integrity, shown by administration of its reverse sequence counterpart which behaves as an inactive control, likely due to a poor conformational flexibility which makes it unable to dynamically perturb biomembrane-like environments. Our results demonstrate that one of the AD-relevant, soluble and secreted N-terminally truncated tau forms can early contribute to pathology outside of neurons causing alterations in synaptic activity at presynaptic level, independently of overt neurodegeneration.
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Affiliation(s)
| | | | - Gabriele Ciasca
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Maria Teresa Ciotti
- Institute of Cellular Biology and Neuroscience, CNR, IRCSS Santa Lucia Foundation, Rome, Italy
| | - Anna Pittaluga
- Department of Pharmacy, Pharmacology and Toxicology Section, University of Genoa, Genoa, Viale Cembrano, Italy
| | - Gunedalina Olivero
- Department of Pharmacy, Pharmacology and Toxicology Section, University of Genoa, Genoa, Viale Cembrano, Italy
| | - Marco Feligioni
- European Brain Research Institute, Rome, Italy
- Department of Neurorehabilitation Sciences, Casa Cura Policlinico, Milan, Italy
| | | | | | | | | | - Danilo Milardi
- Institute of Biostructures and Bioimaging, CNR, Catania, Italy
| | | | - De Spirito Marco
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Massimiliano Papi
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Anna Atlante
- Institute of Biomembranes and Bioenergetics, CNR, Bari, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Viale Benedetto XV, Italy
| | - Antonella Bobba
- Institute of Biomembranes and Bioenergetics, CNR, Bari, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Viale Benedetto XV, Italy
| | - Antonella Borreca
- Institute of Cellular Biology and Neuroscience, CNR, IRCSS Santa Lucia Foundation, Rome, Italy
| | | | - Giuseppina Amadoro
- European Brain Research Institute, Rome, Italy
- Institute of Translational Pharmacology, CNR, Rome, Italy
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41
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Forner S, Baglietto-Vargas D, Martini AC, Trujillo-Estrada L, LaFerla FM. Synaptic Impairment in Alzheimer's Disease: A Dysregulated Symphony. Trends Neurosci 2017; 40:347-357. [PMID: 28494972 DOI: 10.1016/j.tins.2017.04.002] [Citation(s) in RCA: 278] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/13/2017] [Accepted: 04/14/2017] [Indexed: 11/30/2022]
Abstract
Alzheimer's disease (AD) is characterized by memory loss, cognitive decline, and devastating neurodegeneration, not only as a result of the extracellular accumulation of beta-amyloid peptide (Aβ) and intracellular accumulation of tau, but also as a consequence of the dysfunction and loss of synapses. Although significant advances have been made in our understanding of the relationship of the pathological role of Aβ and tau in synapse dysfunction, several questions remain as to how Aβ and tau interdependently cause impairments in synaptic function in AD. Overall, more insight into these questions should enable researchers in this field to develop novel therapeutic targets to mitigate or delay the cognitive deficits associated with this devastating disease.
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Affiliation(s)
- Stefania Forner
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697, USA
| | - David Baglietto-Vargas
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697, USA
| | - Alessandra C Martini
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697, USA
| | - Laura Trujillo-Estrada
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697, USA
| | - Frank M LaFerla
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697, USA; Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA.
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42
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Kuznetsov IA, Kuznetsov AV. Simulating tubulin-associated unit transport in an axon: using bootstrapping for estimating confidence intervals of best-fit parameter values obtained from indirect experimental data. Proc Math Phys Eng Sci 2017; 473:20170045. [PMID: 28588409 DOI: 10.1098/rspa.2017.0045] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 04/03/2017] [Indexed: 02/06/2023] Open
Abstract
In this paper, we first develop a model of axonal transport of tubulin-associated unit (tau) protein. We determine the minimum number of parameters necessary to reproduce published experimental results, reducing the number of parameters from 18 in the full model to eight in the simplified model. We then address the following questions: Is it possible to estimate parameter values for this model using the very limited amount of published experimental data? Furthermore, is it possible to estimate confidence intervals for the determined parameters? The idea that is explored in this paper is based on using bootstrapping. Model parameters were estimated by minimizing the objective function that simulates the discrepancy between the model predictions and experimental data. Residuals were then identified by calculating the differences between the experimental data and model predictions. New, surrogate 'experimental' data were generated by randomly resampling residuals. By finding sets of best-fit parameters for a large number of surrogate data the histograms for the model parameters were produced. These histograms were then used to estimate confidence intervals for the model parameters, by using the percentile bootstrap. Once the model was calibrated, we applied it to analysing some features of tau transport that are not accessible to current experimental techniques.
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Affiliation(s)
- I A Kuznetsov
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - A V Kuznetsov
- Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC 27695-7910, USA
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43
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Guo T, Noble W, Hanger DP. Roles of tau protein in health and disease. Acta Neuropathol 2017; 133:665-704. [PMID: 28386764 PMCID: PMC5390006 DOI: 10.1007/s00401-017-1707-9] [Citation(s) in RCA: 546] [Impact Index Per Article: 78.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/26/2017] [Accepted: 03/26/2017] [Indexed: 01/18/2023]
Abstract
Tau is well established as a microtubule-associated protein in neurons. However, under pathological conditions, aberrant assembly of tau into insoluble aggregates is accompanied by synaptic dysfunction and neural cell death in a range of neurodegenerative disorders, collectively referred to as tauopathies. Recent advances in our understanding of the multiple functions and different locations of tau inside and outside neurons have revealed novel insights into its importance in a diverse range of molecular pathways including cell signalling, synaptic plasticity, and regulation of genomic stability. The present review describes the physiological and pathophysiological properties of tau and how these relate to its distribution and functions in neurons. We highlight the post-translational modifications of tau, which are pivotal in defining and modulating tau localisation and its roles in health and disease. We include discussion of other pathologically relevant changes in tau, including mutation and aggregation, and how these aspects impinge on the propensity of tau to propagate, and potentially drive neuronal loss, in diseased brain. Finally, we describe the cascade of pathological events that may be driven by tau dysfunction, including impaired axonal transport, alterations in synapse and mitochondrial function, activation of the unfolded protein response and defective protein degradation. It is important to fully understand the range of neuronal functions attributed to tau, since this will provide vital information on its involvement in the development and pathogenesis of disease. Such knowledge will enable determination of which critical molecular pathways should be targeted by potential therapeutic agents developed for the treatment of tauopathies.
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Affiliation(s)
- Tong Guo
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE5 9NU, UK
| | - Wendy Noble
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE5 9NU, UK
| | - Diane P Hanger
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE5 9NU, UK.
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44
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Brady ST, Morfini GA. Regulation of motor proteins, axonal transport deficits and adult-onset neurodegenerative diseases. Neurobiol Dis 2017; 105:273-282. [PMID: 28411118 DOI: 10.1016/j.nbd.2017.04.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/17/2017] [Accepted: 04/10/2017] [Indexed: 01/07/2023] Open
Abstract
Neurons affected in a wide variety of unrelated adult-onset neurodegenerative diseases (AONDs) typically exhibit a "dying back" pattern of degeneration, which is characterized by early deficits in synaptic function and neuritic pathology long before neuronal cell death. Consistent with this observation, multiple unrelated AONDs including Alzheimer's disease, Parkinson's disease, Huntington's disease, and several motor neuron diseases feature early alterations in kinase-based signaling pathways associated with deficits in axonal transport (AT), a complex cellular process involving multiple intracellular trafficking events powered by microtubule-based motor proteins. These pathogenic events have important therapeutic implications, suggesting that a focus on preservation of neuronal connections may be more effective to treat AONDs than addressing neuronal cell death. While the molecular mechanisms underlying AT abnormalities in AONDs are still being analyzed, evidence has accumulated linking those to a well-established pathological hallmark of multiple AONDs: altered patterns of neuronal protein phosphorylation. Here, we present a short overview on the biochemical heterogeneity of major motor proteins for AT, their regulation by protein kinases, and evidence revealing cell type-specific AT specializations. When considered together, these findings may help explain how independent pathogenic pathways can affect AT differentially in the context of each AOND.
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Affiliation(s)
- Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA 02543, USA.
| | - Gerardo A Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA 02543, USA.
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45
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46
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Yao ES, Tang Y, Liu XH, Wang MH. TPPU protects tau from H 2O 2-induced hyperphosphorylation in HEK293/tau cells by regulating PI3K/AKT/GSK-3β pathway. ACTA ACUST UNITED AC 2016; 36:785-790. [PMID: 27924507 DOI: 10.1007/s11596-016-1662-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/17/2016] [Indexed: 12/12/2022]
Abstract
Neurofibrillary pathology of abnormally hyperphosphorylated tau is a hallmark of Alzheimer's disease (AD) and other tauopathies. Phosphatidylinositol 3-kinase (PI3K)/Akt/glycogen synthase kinase-3 beta (GSK-3β) signaling pathway is pivotal for tau phosphorylation. Inhibition of soluble epoxide hydrolase (sEH) metabolism has been shown to effectively increase the accumulation of epoxyeicosatrienoic acids (EETs), which are cytochrome P450 metabolites of arachidonic acid and have been demonstrated to have neuroprotective effects. However, little is known about the role of sEH in tau phosphorylation. The present study investigated the role of a sEH inhibitor, 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl] urea (TPPU), on H2O2-induced tau phosphorylation and the underlying signaling pathway in human embryonic kidney 293 (HEK293)/Tau cells. We found that the cell viability was increased after TPPU treatment compared to control in oxidative stress. Western blotting and immunofluorescence results showed that the levels of phosphorylated tau at Thr231 and Ser396 sites were increased in H2O2-treated cells but dropped to normal levels after TPPU administration. H2O2 induced an obvious decreased phosphorylation of GSK-3β at Ser9, an inactive form of GSK-3β, while there were no changes of phosphorylation of GSK-3β at Tyr216. TPPU pretreatment maintained GSK-3β Ser 9 phosphorylation. Moreover, Western blotting results showed that TPPU upregulated the expression of p-Akt. The protective effects of TPPU were found to be inhibited by wortmannin (WT, a specific PI3K inhibitor). In conclusion, these results suggested that the protective effect of TPPU on H2O2-induced oxidative stress is associated with PI3K/Akt/GSK-3β pathway.
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Affiliation(s)
- En-Sheng Yao
- Department of Neurology, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Neurology, Shihezi University, Shihezi, 832008, China
| | - Yan Tang
- Department of Geriatrics, The First Affiliated Hospital, School of Medicine, Shihezi University, Shihezi, 832008, China
| | - Xing-Hua Liu
- Department of Neurology, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Ming-Huan Wang
- Department of Neurology, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, 430030, China
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47
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Tiernan CT, Combs B, Cox K, Morfini G, Brady ST, Counts SE, Kanaan NM. Pseudophosphorylation of tau at S422 enhances SDS-stable dimer formation and impairs both anterograde and retrograde fast axonal transport. Exp Neurol 2016; 283:318-29. [PMID: 27373205 PMCID: PMC4992631 DOI: 10.1016/j.expneurol.2016.06.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/22/2016] [Accepted: 06/28/2016] [Indexed: 12/17/2022]
Abstract
In Alzheimer's disease (AD), tau undergoes numerous modifications, including increased phosphorylation at serine-422 (pS422). In the human brain, pS422 tau protein is found in prodromal AD, correlates well with cognitive decline and neuropil thread pathology, and appears associated with increased oligomer formation and exposure of the N-terminal phosphatase-activating domain (PAD). However, whether S422 phosphorylation contributes to toxic mechanisms associated with disease-related forms of tau remains unknown. Here, we report that S422-pseudophosphorylated tau (S422E) lengthens the nucleation phase of aggregation without altering the extent of aggregation or the types of aggregates formed. When compared to unmodified tau aggregates, the S422E modification significantly increased the amount of SDS-stable tau dimers, despite similar levels of immunoreactivity with an oligomer-selective antibody (TOC1) and another antibody that reports PAD exposure (TNT1). Vesicle motility assays in isolated squid axoplasm further revealed that S422E tau monomers inhibited anterograde, kinesin-1 dependent fast axonal transport (FAT). Unexpectedly, and unlike unmodified tau aggregates, which selectively inhibit anterograde FAT, aggregates composed of S422E tau were found to inhibit both anterograde and retrograde FAT. Highlighting the relevance of these findings to human disease, pS422 tau was found to colocalize with tau oligomers and with a fraction of tau showing increased PAD exposure in the human AD brain. This study identifies novel effects of pS422 on tau biochemical properties, including prolonged nucleation and enhanced dimer formation, which correlate with a distinct inhibitory effect on FAT. Taken together, these findings identify a novel mechanistic basis by which pS422 confers upon tau a toxic effect that may directly contribute to axonal dysfunction in AD and other tauopathies.
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Affiliation(s)
- Chelsea T Tiernan
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Benjamin Combs
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Kristine Cox
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Gerardo Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, IL 60612, USA
| | - Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, IL 60612, USA
| | - Scott E Counts
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI 49503, USA; Department of Family Medicine, Michigan State University, Grand Rapids, MI 49503, USA; Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA; Hauenstein Neuroscience Center, Mercy Health Saint Mary's Hospital, Grand Rapids, MI 49503, USA
| | - Nicholas M Kanaan
- Department of Translational Science and Molecular Medicine, Michigan State University, Grand Rapids, MI 49503, USA; Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA; Hauenstein Neuroscience Center, Mercy Health Saint Mary's Hospital, Grand Rapids, MI 49503, USA.
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