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Salem S, Kilgore MD, Anwer M, Maxan A, Child D, Bird TD, Keene CD, Cicchetti F, Latimer C. Evidence of mutant huntingtin and tau-related pathology within neuronal grafts in Huntington's disease cases. Neurobiol Dis 2024; 198:106542. [PMID: 38810948 DOI: 10.1016/j.nbd.2024.106542] [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: 02/26/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 05/31/2024] Open
Abstract
A number of post-mortem studies conducted in transplanted Huntington's disease (HD) patients from various trials have reported the presence of pathological and misfolded proteins, in particular mutant huntingtin (mHtt) and phosphorylated tau neuropil threads, in the healthy grafted tissue. Here, we extended these observations with histological analysis of post-mortem tissue from three additional HD patients who had received similar striatal allografts from the fetal tissue transplantation trial conducted in Los Angeles in 1998. Immunohistochemical staining was performed using anti-mHtt antibodies, EM48 and MW7, as well as anti-hyperphosphorylated tau antibodies, AT8 and CP13. Immunofluorescence was used to assess the colocalization of EM48+ mHtt aggregates with the neuronal marker MAP2 and/or the extracellular matrix protein phosphacan in both the host and grafts. We confirmed the presence of mHtt aggregates within grafts of all three cases as well as tau neuropil threads in the grafts of two of the three transplanted HD patients. Phosphorylated tau was also variably expressed in the host cerebral cortex of all three subjects. While mHtt inclusions were present within neurons (immunofluorescence co-localization of MAP2 and EM48) as well as within the extracellular matrix of the host (immunofluorescence co-localization of phosphacan and EM48), their localization was limited to the extracellular matrix in the grafted tissue. This study corroborates previous findings that both mHtt and tau pathology can be found in the host and grafts of HD patients years post-grafting.
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Affiliation(s)
- Shireen Salem
- Centre de Recherche du CHU de Québec, Axe Neurosciences, T2-07, 2705, Boulevard Laurier, Québec, QC G1V 4G2, Canada; Departement de Médecine Moléculaire, Université Laval, Québec, QC, Canada
| | - Mitchell D Kilgore
- Department of Laboratory Medicine and Pathology, Neuropathology Division, University of Washington, Seattle, WA, USA
| | - Mehwish Anwer
- Centre de Recherche du CHU de Québec, Axe Neurosciences, T2-07, 2705, Boulevard Laurier, Québec, QC G1V 4G2, Canada; Departement de Psychiatrie et Neurosciences, Université Laval, Québec, QC, Canada
| | - Alexander Maxan
- Centre de Recherche du CHU de Québec, Axe Neurosciences, T2-07, 2705, Boulevard Laurier, Québec, QC G1V 4G2, Canada; Departement de Psychiatrie et Neurosciences, Université Laval, Québec, QC, Canada
| | - Dan Child
- Department of Laboratory Medicine and Pathology, Neuropathology Division, University of Washington, Seattle, WA, USA
| | - Thomas D Bird
- Department of Neurology, University of Washington, Seattle, WA, USA; Geriatric Research, Education, and Clinical Center (GRECC), VA Puget Sound Health Care System, Seattle, WA, USA
| | - C Dirk Keene
- Department of Laboratory Medicine and Pathology, Neuropathology Division, University of Washington, Seattle, WA, USA
| | - Francesca Cicchetti
- Centre de Recherche du CHU de Québec, Axe Neurosciences, T2-07, 2705, Boulevard Laurier, Québec, QC G1V 4G2, Canada; Departement de Médecine Moléculaire, Université Laval, Québec, QC, Canada; Departement de Psychiatrie et Neurosciences, Université Laval, Québec, QC, Canada.
| | - Caitlin Latimer
- Department of Laboratory Medicine and Pathology, Neuropathology Division, University of Washington, Seattle, WA, USA.
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2
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Yang J, Shen N, Shen J, Yang Y, Li HL. Complicated Role of Post-translational Modification and Protease-Cleaved Fragments of Tau in Alzheimer's Disease and Other Tauopathies. Mol Neurobiol 2024; 61:4712-4731. [PMID: 38114762 PMCID: PMC11236937 DOI: 10.1007/s12035-023-03867-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 12/07/2023] [Indexed: 12/21/2023]
Abstract
Tau, a microtubule-associated protein predominantly localized in neuronal axons, plays a crucial role in promoting microtubule assembly, stabilizing their structure, and participating in axonal transport. Perturbations in tau's structure and function are implicated in the pathogenesis of neurodegenerative diseases collectively known as tauopathies, the most common disorder of which is Alzheimer's disease (AD). In tauopathies, it has been found that tau has a variety of post-translational modification (PTM) abnormalities and/or tau is cleaved into a variety of fragments by some specific proteolytic enzymes; however, the precise contributions of these abnormal modifications and fragments to disease onset and progression remain incompletely understood. Herein, we provide an overview about the involvement of distinctive abnormal tau PTMs and different tau fragments in the pathogenesis of AD and other tauopathies and discuss the involvement of proteolytic enzymes such as caspases, calpains, and asparagine endopeptidase in mediating tau cleavage while also addressing the intercellular transmission role played by tau. We anticipate that further exploration into PTMs and fragmented forms of tau will yield valuable insights for diagnostic approaches and therapeutic interventions targeting AD and other related disorders.
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Affiliation(s)
- Jie Yang
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Naiting Shen
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jianying Shen
- Department of Histology and Embryology, School of Basic Medicine, Key Laboratory of Education Ministry, Hubei Province of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ying Yang
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry, Hubei Province of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hong-Lian Li
- Department of Histology and Embryology, School of Basic Medicine, Key Laboratory of Education Ministry, Hubei Province of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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3
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Chu D, Yang X, Wang J, Zhou Y, Gu JH, Miao J, Wu F, Liu F. Tau truncation in the pathogenesis of Alzheimer's disease: a narrative review. Neural Regen Res 2024; 19:1221-1232. [PMID: 37905868 DOI: 10.4103/1673-5374.385853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 07/25/2023] [Indexed: 11/02/2023] Open
Abstract
ABSTRACT Alzheimer's disease is characterized by two major neuropathological hallmarks-the extracellular β-amyloid plaques and intracellular neurofibrillary tangles consisting of aggregated and hyperphosphorylated Tau protein. Recent studies suggest that dysregulation of the microtubule-associated protein Tau, especially specific proteolysis, could be a driving force for Alzheimer's disease neurodegeneration. Tau physiologically promotes the assembly and stabilization of microtubules, whereas specific truncated fragments are sufficient to induce abnormal hyperphosphorylation and aggregate into toxic oligomers, resulting in them gaining prion-like characteristics. In addition, Tau truncations cause extensive impairments to neural and glial cell functions and animal cognition and behavior in a fragment-dependent manner. This review summarizes over 60 proteolytic cleavage sites and their corresponding truncated fragments, investigates the role of specific truncations in physiological and pathological states of Alzheimer's disease, and summarizes the latest applications of strategies targeting Tau fragments in the diagnosis and treatment of Alzheimer's disease.
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Affiliation(s)
- Dandan Chu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Xingyue Yang
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Jing Wang
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Yan Zhou
- Department of Biochemistry and Molecular Biology, School of Medicine, Nantong University, Nantong, Jiangsu Province, China
| | - Jin-Hua Gu
- Department of Clinical Pharmacy, Affiliated Maternity and Child Health Care Hospital of Nantong University, Nantong University, Nantong, Jiangsu Province, China
| | - Jin Miao
- Laboratory of Animal Center, Nantong University, Nantong, Jiangsu Province, China
| | - Feng Wu
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Fei Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
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4
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Abyadeh M, Gupta V, Paulo JA, Mahmoudabad AG, Shadfar S, Mirshahvaladi S, Gupta V, Nguyen CTO, Finkelstein DI, You Y, Haynes PA, Salekdeh GH, Graham SL, Mirzaei M. Amyloid-beta and tau protein beyond Alzheimer's disease. Neural Regen Res 2024; 19:1262-1276. [PMID: 37905874 DOI: 10.4103/1673-5374.386406] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 09/07/2023] [Indexed: 11/02/2023] Open
Abstract
ABSTRACT The aggregation of amyloid-beta peptide and tau protein dysregulation are implicated to play key roles in Alzheimer's disease pathogenesis and are considered the main pathological hallmarks of this devastating disease. Physiologically, these two proteins are produced and expressed within the normal human body. However, under pathological conditions, abnormal expression, post-translational modifications, conformational changes, and truncation can make these proteins prone to aggregation, triggering specific disease-related cascades. Recent studies have indicated associations between aberrant behavior of amyloid-beta and tau proteins and various neurological diseases, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis, as well as retinal neurodegenerative diseases like Glaucoma and age-related macular degeneration. Additionally, these proteins have been linked to cardiovascular disease, cancer, traumatic brain injury, and diabetes, which are all leading causes of morbidity and mortality. In this comprehensive review, we provide an overview of the connections between amyloid-beta and tau proteins and a spectrum of disorders.
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Affiliation(s)
| | - Vivek Gupta
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW, Australia
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | | | - Sina Shadfar
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW, Australia
| | - Shahab Mirshahvaladi
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW, Australia
| | - Veer Gupta
- School of Medicine, Deakin University, Geelong, VIC, Australia
| | - Christine T O Nguyen
- Department of Optometry and Vision Sciences, School of Health Sciences, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - David I Finkelstein
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - Yuyi You
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW, Australia
| | - Paul A Haynes
- School of Natural Sciences, Macquarie University, Macquarie Park, NSW, Australia
| | - Ghasem H Salekdeh
- School of Natural Sciences, Macquarie University, Macquarie Park, NSW, Australia
| | - Stuart L Graham
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW, Australia
| | - Mehdi Mirzaei
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW, Australia
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5
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Jellinger KA. Mild cognitive impairment in Huntington's disease: challenges and outlooks. J Neural Transm (Vienna) 2024; 131:289-304. [PMID: 38265518 DOI: 10.1007/s00702-024-02744-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 01/14/2024] [Indexed: 01/25/2024]
Abstract
Although Huntington's disease (HD) has classically been viewed as an autosomal-dominant inherited neurodegenerative motor disorder, cognitive and/or behavioral changes are predominant and often an early manifestation of disease. About 40% of individuals in the presymptomatic period of HD meet the criteria for mild cognitive impairment, later progressing to dementia. The heterogenous spectrum of cognitive decline is characterized by deficits across multiple domains, particularly executive dysfunctions, but the underlying pathogenic mechanisms are still poorly understood. Investigating the pathophysiology of cognitive changes may give insight into important and early neurodegenerative events. Multimodal imaging revealed circuit-wide gray and white matter degenerative processes in several key brain regions, affecting prefronto-striatal/cortico-basal ganglia circuits and many other functional brain networks. Studies in transgenic animal models indicated early synaptic dysfunction, deficient neurotrophic transport and other molecular changes contributing to neuronal death. Synaptopathy within the cerebral cortex, striatum and hippocampus may be particularly important in mediating cognitive and neuropsychiatric manifestations of HD, although many other neuronal systems are involved. The interaction of mutant huntingtin protein (mHTT) with tau and its implication for cognitive impairment in HD is a matter of discussion. Further neuroimaging and neuropathological studies are warranted to better elucidate early pathophysiological mechanisms and to develop validated biomarkers to detect patients' cognitive status during the early stages of the condition significantly to implement effective preventing or management strategies.
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Affiliation(s)
- Kurt A Jellinger
- Institute of Clinical Neurobiology, Alberichgasse 5/13, 1150, Vienna, Austria.
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Rizzi L, Grinberg LT. Exploring the significance of caspase-cleaved tau in tauopathies and as a complementary pathology to phospho-tau in Alzheimer's disease: implications for biomarker development and therapeutic targeting. Acta Neuropathol Commun 2024; 12:36. [PMID: 38419122 PMCID: PMC10900669 DOI: 10.1186/s40478-024-01744-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 02/12/2024] [Indexed: 03/02/2024] Open
Abstract
Tauopathies are neurodegenerative diseases that typically require postmortem examination for a definitive diagnosis. Detecting neurotoxic tau fragments in cerebrospinal fluid (CSF) and serum provides an opportunity for in vivo diagnosis and disease monitoring. Current assays primarily focus on total tau or phospho-tau, overlooking other post-translational modifications (PTMs). Caspase-cleaved tau is a significant component of AD neuropathological lesions, and experimental studies confirm the high neurotoxicity of these tau species. Recent evidence indicates that certain caspase-cleaved tau species, such as D13 and D402, are abundant in AD brain neurons and only show a modest degree of co-occurrence with phospho-tau, meaning caspase-truncated tau pathology is partially distinct and complementary to phospho-tau pathology. Furthermore, these caspase-cleaved tau species are nearly absent in 4-repeat tauopathies. In this review, we will discuss the significance of caspase-cleaved tau in the development of tauopathies, specifically emphasizing its role in AD. In addition, we will explore the potential of caspase-cleaved tau as a biomarker and the advantages for drug development targeting caspase-6. Developing specific and sensitive assays for caspase-cleaved tau in biofluids holds promise for improving the diagnosis and monitoring of tauopathies, providing valuable insights into disease progression and treatment efficacy.
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Affiliation(s)
- Liara Rizzi
- Memory and Aging Center, Department of Neurology, Sandler Neurosciences Center, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
- Department of Neurology, University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Lea T Grinberg
- Memory and Aging Center, Department of Neurology, Sandler Neurosciences Center, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA.
- Department of Pathology, LIM-22, University of São Paulo Medical School, São Paulo, SP, Brazil.
- Department of Pathology, University of California San Francisco, San Francisco, CA, USA.
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7
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Volik PI, Kopeina GS, Zhivotovsky B, Zamaraev AV. Total recall: the role of PIDDosome components in neurodegeneration. Trends Mol Med 2023; 29:996-1013. [PMID: 37716905 DOI: 10.1016/j.molmed.2023.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/23/2023] [Accepted: 08/25/2023] [Indexed: 09/18/2023]
Abstract
The PIDDosome is a multiprotein complex that includes p53-induced protein with a death domain 1 (PIDD1), receptor-interacting protein-associated ICH-1/CED-3 homologous protein with a death domain (RAIDD), and caspase-2, the activation of which is driven by PIDDosome assembly. In addition to the key role of the PIDDosome in the regulation of cell differentiation, tissue homeostasis, and organogenesis and regeneration, caspase-2, RAIDD and PIDD1 engagement in neuronal development was shown. Here, we focus on the involvement of PIDDosome components in neurodegenerative disorders, including retinal neuropathies, different types of brain damage, and Alzheimer's disease (AD), Huntington's disease (HD), and Lewy body disease. We also discuss pathogenic variants of PIDD1, RAIDD, and caspase-2 that are associated with intellectual, behavioral, and psychological abnormalities, together with prospective PIDDosome inhibition strategies and their potential clinical application.
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Affiliation(s)
- Pavel I Volik
- Facuty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; Engelhardt Institute of Molecular Biology, RAS, 119991 Moscow, Russia
| | - Gelina S Kopeina
- Facuty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; Engelhardt Institute of Molecular Biology, RAS, 119991 Moscow, Russia
| | - Boris Zhivotovsky
- Facuty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; Engelhardt Institute of Molecular Biology, RAS, 119991 Moscow, Russia; Division of Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Box 210, 17177 Stockholm, Sweden.
| | - Alexey V Zamaraev
- Facuty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; Engelhardt Institute of Molecular Biology, RAS, 119991 Moscow, Russia.
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8
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Cuellar ME, Yang M, Karavadhi S, Zhang YQ, Zhu H, Sun H, Shen M, Hall MD, Patnaik S, Ashe KH, Walters MA, Pockes S. An electrophilic fragment screening for the development of small molecules targeting caspase-2. Eur J Med Chem 2023; 259:115632. [PMID: 37453329 PMCID: PMC10529632 DOI: 10.1016/j.ejmech.2023.115632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 07/04/2023] [Accepted: 07/09/2023] [Indexed: 07/18/2023]
Abstract
Recent Alzheimer's research has shown increasing interest in the caspase-2 (Casp2) enzyme. However, the available Casp2 inhibitors, which have been pentapeptides or peptidomimetics, face challenges for use as CNS drugs. In this study, we successfully screened a 1920-compound chloroacetamide-based, electrophilic fragment library from Enamine. Our two-point dose screen identified 64 Casp2 hits, which were further evaluated in a ten-point dose-response study to assess selectivity over Casp3. We discovered compounds with inhibition values in the single-digit micromolar and sub-micromolar range, as well as up to 32-fold selectivity for Casp2 over Casp3. Target engagement analysis confirmed the covalent-irreversible binding of the selected fragments to Cys320 at the active site of Casp2. Overall, our findings lay a strong foundation for the future development of small-molecule Casp2 inhibitors.
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Affiliation(s)
- Matthew E Cuellar
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN, 55414, USA
| | - Mu Yang
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN, 55414, USA
| | - Surendra Karavadhi
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Ya-Qin Zhang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Hu Zhu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Hongmao Sun
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Matthew D Hall
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Samarjit Patnaik
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Karen H Ashe
- Department of Neurology, University of Minnesota, 2101 6th Street SE, Minneapolis, MN, 55455, USA
| | - Michael A Walters
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN, 55414, USA.
| | - Steffen Pockes
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN, 55414, USA; Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
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9
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Lepinay E, Cicchetti F. Tau: a biomarker of Huntington's disease. Mol Psychiatry 2023; 28:4070-4083. [PMID: 37749233 DOI: 10.1038/s41380-023-02230-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 07/31/2023] [Accepted: 08/11/2023] [Indexed: 09/27/2023]
Abstract
Developing effective treatments for patients with Huntington's disease (HD)-a neurodegenerative disorder characterized by severe cognitive, motor and psychiatric impairments-is proving extremely challenging. While the monogenic nature of this condition enables to identify individuals at risk, robust biomarkers would still be extremely valuable to help diagnose disease onset and progression, and especially to confirm treatment efficacy. If measurements of cerebrospinal fluid neurofilament levels, for example, have demonstrated use in recent clinical trials, other proteins may prove equal, if not greater, relevance as biomarkers. In fact, proteins such as tau could specifically be used to detect/predict cognitive affectations. We have herein reviewed the literature pertaining to the association between tau levels and cognitive states, zooming in on Alzheimer's disease, Parkinson's disease and traumatic brain injury in which imaging, cerebrospinal fluid, and blood samples have been interrogated or used to unveil a strong association between tau and cognition. Collectively, these areas of research have accrued compelling evidence to suggest tau-related measurements as both diagnostic and prognostic tools for clinical practice. The abundance of information retrieved in this niche of study has laid the groundwork for further understanding whether tau-related biomarkers may be applied to HD and guide future investigations to better understand and treat this disease.
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Affiliation(s)
- Eva Lepinay
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada
- Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada
| | - Francesca Cicchetti
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.
- Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada.
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10
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Opland CK, Bryan MR, Harris B, McGillion-Moore J, Tian X, Chen Y, Itano MS, Diering GH, Meeker RB, Cohen TJ. Activity-dependent tau cleavage by caspase-3 promotes neuronal dysfunction and synaptotoxicity. iScience 2023; 26:106905. [PMID: 37305696 PMCID: PMC10251131 DOI: 10.1016/j.isci.2023.106905] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/08/2023] [Accepted: 05/12/2023] [Indexed: 06/13/2023] Open
Abstract
Tau-mediated toxicity is associated with cognitive decline and Alzheimer's disease (AD) progression. In particular, tau post-translational modifications (PTMs) are thought to generate aberrant tau species resulting in neuronal dysfunction. Despite being well characterized in postmortem AD brain, it is unclear how caspase-mediated C-terminal tau cleavage promotes neurodegeneration, as few studies have developed the models to dissect this pathogenic mechanism. Here, we show that proteasome impairment results in cleaved tau accumulation at the post-synaptic density (PSD), a process that is modulated by neuronal activity. Cleaved tau (at residue D421) impairs neuronal firing and causes inefficient initiation of network bursts, consistent with reduced excitatory drive. We propose that reduced neuronal activity, or silencing, is coupled to proteasome dysfunction, which drives cleaved tau accumulation at the PSD and subsequent synaptotoxicity. Our study connects three common themes in the progression of AD: impaired proteostasis, caspase-mediated tau cleavage, and synapse degeneration.
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Affiliation(s)
- Carli K. Opland
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Miles R. Bryan
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Braxton Harris
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jake McGillion-Moore
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Xu Tian
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Youjun Chen
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Michelle S. Itano
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Graham H. Diering
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Rick B. Meeker
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Todd J. Cohen
- UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599-7260, USA
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11
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Reinhardt L, Musacchio F, Bichmann M, Behrendt A, Ercan-Herbst E, Stein J, Becher I, Haberkant P, Mader J, Schöndorf DC, Schmitt M, Korffmann J, Reinhardt P, Pohl C, Savitski M, Klein C, Gasparini L, Fuhrmann M, Ehrnhoefer DE. Dual truncation of tau by caspase-2 accelerates its CHIP-mediated degradation. Neurobiol Dis 2023; 182:106126. [PMID: 37086756 DOI: 10.1016/j.nbd.2023.106126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/30/2023] [Accepted: 04/12/2023] [Indexed: 04/24/2023] Open
Abstract
Intraneuronal aggregates of the microtubule binding protein Tau are a hallmark of different neurodegenerative diseases including Alzheimer's disease (AD). In these aggregates, Tau is modified by posttranslational modifications such as phosphorylation as well as by proteolytic cleavage. Here we identify a novel Tau cleavage site at aspartate 65 (D65) that is specific for caspase-2. In addition, we show that the previously described cleavage site at D421 is also efficiently processed by caspase-2, and both sites are cleaved in human brain samples. Caspase-2-generated Tau fragments show increased aggregation potential in vitro, but do not accumulate in vivo after AAV-mediated overexpression in mouse hippocampus. Interestingly, we observe that steady-state protein levels of caspase-2 generated Tau fragments are low in our in vivo model despite strong RNA expression, suggesting efficient clearance. Consistent with this hypothesis, we find that caspase-2 cleavage significantly improves the recognition of Tau by the ubiquitin E3 ligase CHIP, leading to increased ubiquitination and faster degradation of Tau fragments. Taken together our data thus suggest that CHIP-induced ubiquitination is of particular importance for the clearance of caspase-2 generated Tau fragments in vitro and in vivo.
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Affiliation(s)
- Lydia Reinhardt
- BioMed X Institute, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany; AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Fabrizio Musacchio
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative Diseases (DZNE), Venusberg-Campus 1, Building 99, 53127 Bonn, Germany
| | - Maria Bichmann
- BioMed X Institute, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany
| | - Annika Behrendt
- BioMed X Institute, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany
| | - Ebru Ercan-Herbst
- BioMed X Institute, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany
| | - Juliane Stein
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Isabelle Becher
- European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Per Haberkant
- European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Julia Mader
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - David C Schöndorf
- BioMed X Institute, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany; AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Melanie Schmitt
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Jürgen Korffmann
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Peter Reinhardt
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Christian Pohl
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Mikhail Savitski
- European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Corinna Klein
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Laura Gasparini
- AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany
| | - Martin Fuhrmann
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative Diseases (DZNE), Venusberg-Campus 1, Building 99, 53127 Bonn, Germany
| | - Dagmar E Ehrnhoefer
- BioMed X Institute, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany; AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen am Rhein, Germany.
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12
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Mees I, Nisbet R, Hannan A, Renoir T. Implications of Tau Dysregulation in Huntington's Disease and Potential for New Therapeutics. J Huntingtons Dis 2023; 12:1-13. [PMID: 37092231 DOI: 10.3233/jhd-230569] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder. The disease, characterized by motor, cognitive, and psychiatric impairments, is caused by the expansion of a CAG repeat in the huntingtin gene. Despite the discovery of the mutation in 1993, no disease-modifying treatments are yet available. Understanding the molecular and cellular mechanisms involved in HD is therefore crucial for the development of novel treatments. Emerging research has found that HD might be classified as a secondary tauopathy, with the presence of tau insoluble aggregates in late HD. Increased total tau protein levels have been observed in both HD patients and animal models of HD. Tau hyperphosphorylation, the main feature of tau pathology, has also been investigated and our own published results suggest that the protein phosphorylation machinery is dysregulated in the early stages of HD in R6/1 transgenic mice, primarily in the cortex and striatum. Protein phosphorylation, catalysed by kinases, regulates numerous cellular mechanisms and has been shown to be dysregulated in other neurodegenerative disorders, including Alzheimer's disease. While it is still unclear how the mutation in the huntingtin gene leads to tau dysregulation in HD, several hypotheses have been explored. Evidence suggests that the mutant huntingtin does not directly interact with tau, but instead interacts with tau kinases, phosphatases, and proteins involved in tau alternative splicing, which could result in tau dysregulation as observed in HD. Altogether, there is increasing evidence that tau is undergoing pathological changes in HD and may be a good therapeutic target.
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Affiliation(s)
- Isaline Mees
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Rebecca Nisbet
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Anthony Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
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13
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Pockes S, Walters MA, Ashe KH. Targeting caspase-2 interactions with tau in Alzheimer's disease and related dementias. Transl Res 2023; 254:34-40. [PMID: 36343883 PMCID: PMC9991976 DOI: 10.1016/j.trsl.2022.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 10/26/2022] [Accepted: 10/30/2022] [Indexed: 11/06/2022]
Abstract
Targeting amyloid-β plaques and tau tangles has failed to provide effective treatments for Alzheimer's disease and related dementias (ADRD). A more fruitful pathway to ADRD therapeutics may be the development of therapies that target common signaling pathways that disrupt synaptic connections and impede communication between neurons. In this review, we present our characterization of a signaling pathway common to several neurological diseases featuring dementia including Alzheimer's disease, frontotemporal dementia, Lewy body dementia, and Huntington's disease. This signaling pathway features the cleavage of tau by caspase-2 (Casp2) yielding Δtau314 (Casp2/tau/Δtau314). Through a not yet fully delineated mechanism, Δtau314 catalyzes the mislocalization and accumulation of tau to dendritic spines leading to the internalization of AMPA receptors and the concomitant weakening of synaptic transmission. Here, we review the accumulated evidence supporting Casp2 as a druggable target and its importance in ADRD. Additionally, we provide a brief overview of our initial medicinal chemistry explorations aimed at the preparation of novel, brain penetrant Casp2 inhibitors. We anticipate that this review will spark broader interest in Casp2 as a target for restoring synaptic dysfunction in ADRD.
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Affiliation(s)
- Steffen Pockes
- Institute of Pharmacy, University of Regensburg, Regensburg, Germany; Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota; Department of Neurology, University of Minnesota, Minneapolis, Minnesota.
| | - Michael A Walters
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota.
| | - Karen H Ashe
- Department of Neurology, University of Minnesota, Minneapolis, Minnesota.
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14
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Salem S, Cicchetti F. Untangling the Role of Tau in Huntington's Disease Pathology. J Huntingtons Dis 2023; 12:15-29. [PMID: 36806513 DOI: 10.3233/jhd-220557] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
There is increasing evidence for the presence of pathological forms of tau in tissues of both Huntington's disease (HD) patients and animal models of this condition. While cumulative studies of the past decade have led to the proposition that this disorder could also be considered a tauopathy, the implications of tau in cellular toxicity and consequent behavioral impairments are largely unknown. In fact, recent animal work has challenged the contributory role of tau in HD pathogenesis/pathophysiology. This review presents the supporting and opposing arguments for the involvement of tau in HD, highlighting the discrepancies that have emerged. Reflecting on what is known in other tauopathies, the putative mechanisms through which tau could initiate and/or contribute to pathology are discussed, shedding light on the future research directions that could be considered to confirm, or rule out, the clinical relevance of tau in HD.
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Affiliation(s)
- Shireen Salem
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada
| | - Francesca Cicchetti
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada.,Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada
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15
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Hlynialuk C, Kemper L, Leinonen-Wright K, Petersen RC, Ashe K, Smith B. Caspase-2 mRNA levels are not elevated in mild cognitive impairment, Alzheimer's disease, Huntington's disease, or Lewy Body dementia. PLoS One 2022; 17:e0274784. [PMID: 36129947 PMCID: PMC9491574 DOI: 10.1371/journal.pone.0274784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 09/05/2022] [Indexed: 11/28/2022] Open
Abstract
Caspase-2 is a member of the caspase family that exhibits both apoptotic and non-apoptotic properties, and has been shown to mediate synaptic deficits in models of several neurological conditions, including Alzheimer's disease (AD), Huntington's disease (HD), and Lewy Body dementia (LBD). Our lab previously reported that caspase-2 protein levels are elevated in these diseases, leading us to hypothesize that elevated caspase-2 protein levels are due to increased transcription of caspase-2 mRNA. There are two major isoforms of caspase-2 mRNA, caspase-2L and caspase-2S. We tested our hypothesis by measuring the levels of these mRNA isoforms normalized to levels of RPL13 mRNA, a reference gene that showed no disease-associated changes. Here, we report no increases in caspase-2L mRNA levels in any of the three diseases studied, AD (with mild cognitive impairment (MCI)), HD and LBD, disproving our hypothesis. Caspase-2S mRNA showed a non-significant downward trend in AD. We also analyzed expression levels of SNAP25 and βIII-tubulin mRNA. SNAP25 mRNA was significantly lower in AD and there were downward trends in MCI, LBD, and HD. βIII-tubulin mRNA expression remained unchanged between disease groups and controls. These findings indicate that factors besides transcriptional regulation cause increases in caspase-2 protein levels. The reduction of SNAP25 mRNA expression suggests that presynaptic dysfunction contributes to cognitive deficits in neurodegeneration.
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Affiliation(s)
- Chris Hlynialuk
- N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, United States of America
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States of America
| | - Lisa Kemper
- N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, United States of America
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States of America
| | - Kailee Leinonen-Wright
- N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, United States of America
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States of America
| | - Ronald C. Petersen
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - Karen Ashe
- N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, United States of America
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States of America
- Minneapolis VA Medical Center, Minneapolis, MN, United States of America
| | - Benjamin Smith
- N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, United States of America
- Department of Neurology, University of Minnesota, Minneapolis, MN, United States of America
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16
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White A, McGlone A, Gomez-Pastor R. Protein Kinase CK2 and Its Potential Role as a Therapeutic Target in Huntington's Disease. Biomedicines 2022; 10:1979. [PMID: 36009526 PMCID: PMC9406209 DOI: 10.3390/biomedicines10081979] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/10/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
Huntington's Disease (HD) is a devastating neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the HTT gene, for which no disease modifying therapies are currently available. Much of the recent research has focused on developing therapies to directly lower HTT expression, and while promising, these therapies have presented several challenges regarding administration and efficacy. Another promising therapeutic approach is the modulation of HTT post-translational modifications (PTMs) that are dysregulated in disease and have shown to play a key role in HTT toxicity. Among all PTMs, modulation of HTT phosphorylation has been proposed as an attractive therapeutic option due to the possibility of orally administering specific kinase effectors. One of the kinases described to participate in HTT phosphorylation is Protein Kinase CK2. CK2 has recently emerged as a target for the treatment of several neurological and psychiatric disorders, although its role in HD remains controversial. While pharmacological studies in vitro inhibiting CK2 resulted in reduced HTT phosphorylation and increased toxicity, genetic approaches in mouse models of HD have provided beneficial effects. In this review we discuss potential therapeutic approaches related to the manipulation of HTT-PTMs with special emphasis on the role of CK2 as a therapeutic target in HD.
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Affiliation(s)
| | | | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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17
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Steuer EL, Kemper LJ, Hlynialuk CJW, Leinonen-Wright K, Montonye ML, Lapcinski IP, Forster CL, Ashe KH, Liu P. Blocking Site-Specific Cleavage of Human Tau Delays Progression of Disease-Related Phenotypes in Genetically Matched Tau-Transgenic Mice Modeling Frontotemporal Dementia. J Neurosci 2022; 42:4737-4754. [PMID: 35508385 PMCID: PMC9186797 DOI: 10.1523/jneurosci.0543-22.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/22/2022] [Accepted: 04/28/2022] [Indexed: 11/21/2022] Open
Abstract
Studies have recently demonstrated that a caspase-2-mediated cleavage of human tau (htau) at asparate-314 (D314) is responsible for cognitive deficits and neurodegeneration in mice modeling frontotemporal dementia (FTD). However, these animal studies may be confounded by flaws in their model systems, such as endogenous functional gene disruption and inequivalent transgene expression. To avoid these weaknesses, we examined the pathogenic role of this site-specific htau cleavage in FTD using genetically matched htau targeted-insertion mouse lines: rT2 and rT3. Both male and female mice were included in this study. rT2 mice contain a single copy of the FTD-linked htau proline-to-leucine mutation at amino acid 301 (htau P301L), inserted into a neutral site to avoid dysregulation of host gene expression. The similarly constructed rT3 mice harbor an additional D314-to-glutamate (D314E) mutation that blocks htau cleavage. We demonstrate that htau transgene expression occurs primarily in the forebrain at similar levels in rT2 and rT3 mice. Importantly, expression of the cleavage-resistant D314E mutant delays transgene-induced tau accumulation in the postsynaptic density, brain atrophy, hippocampal neurodegeneration, and spatial memory impairment, without altering age-related progression of pathologic tau conformation and phosphorylation. Our comprehensive investigation of age-dependent disease phenotypes associated with the htau P301L variant in precisely engineered FTD-modeling mice unveils a transiently protective effect of blocking htau cleavage at D314. Findings of this study advance our understanding of the contribution of this tau cleavage to the pathogenesis of FTD, and aid the development of effective dementia-targeting therapies.SIGNIFICANCE STATEMENT A site-specific and caspase-2-mediated cleavage of human tau plays a pathologic role in dementia. In this study, we investigate the contribution of this cleavage to the pathogenesis of frontotemporal dementia (FTD) using two genetically matched, tau-transgene targeted-insertion mouse lines that differ only by a cleavage-resistant mutation. The use of these mice avoids confounding effects associated with the random integration of tau transgenes to the mouse genome and allows us to comprehensively evaluate the impact of the tau cleavage on FTD phenotypes. Our data reveal that blocking this tau cleavage delays memory impairment and neurodegeneration of FTD-modeling mice. These findings improve our understanding of the pathogenic mechanisms underlying FTD and will facilitate the development of effective therapeutics.
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Affiliation(s)
- Elizabeth L Steuer
- N. Bud Grossman Center for Memory Research and Care
- Department of Neurology
| | - Lisa J Kemper
- N. Bud Grossman Center for Memory Research and Care
- Department of Neurology
| | | | | | | | - Ian P Lapcinski
- N. Bud Grossman Center for Memory Research and Care
- Department of Neurology
| | - Colleen L Forster
- N. Bud Grossman Center for Memory Research and Care
- UMN Academic Health Center Biological Materials Procurement Network, University of Minnesota, Minneapolis, Minnesota 55455
| | - Karen H Ashe
- N. Bud Grossman Center for Memory Research and Care
- Department of Neurology
- Geriatric Research, Education, and Clinical Centers, Veterans Affairs Medical Center, Minneapolis, Minnesota 55417
| | - Peng Liu
- N. Bud Grossman Center for Memory Research and Care
- Department of Neurology
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18
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Singh G, Liu P, Yao KR, Strasser JM, Hlynialuk C, Leinonen-Wright K, Teravskis PJ, Choquette JM, Ikramuddin J, Bresinsky M, Nelson KM, Liao D, Ashe KH, Walters MA, Pockes S. Caspase-2 Inhibitor Blocks Tau Truncation and Restores Excitatory Neurotransmission in Neurons Modeling FTDP-17 Tauopathy. ACS Chem Neurosci 2022; 13:1549-1557. [PMID: 35522720 DOI: 10.1021/acschemneuro.2c00100] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Synaptic and cognitive deficits mediated by a severe reduction in excitatory neurotransmission caused by a disproportionate accumulation of the neuronal protein tau in dendritic spines is a fundamental mechanism that has been found repeatedly in models of tauopathies, including Alzheimer's disease, Lewy body dementia, frontotemporal dementia, and traumatic brain injury. Synapses thus damaged may contribute to dementia, among the most feared cause of debilitation in the elderly, and currently there are no treatments to repair them. Caspase-2 (Casp2) is an essential component of this pathological cascade. Although it is believed that Casp2 exerts its effects by hydrolyzing tau at aspartate-314, forming Δtau314, it is also possible that a noncatalytic mechanism is involved because catalytically dead Casp2 is biologically active in at least one relevant cellular pathway, that is, autophagy. To decipher whether the pathological effects of Casp2 on synaptic function are due to its catalytic or noncatalytic properties, we discovered and characterized a new Casp2 inhibitor, compound 1 [pKi (Casp2) = 8.12], which is 123-fold selective versus Casp3 and >2000-fold selective versus Casp1, Casp6, Casp7, and Casp9. In an in vitro assay based on Casp2-mediated cleavage of tau, compound 1 blocked the production of Δtau314. Importantly, compound 1 prevented tau from accumulating excessively in dendritic spines and rescued excitatory neurotransmission in cultured primary rat hippocampal neurons expressing the P301S tau variant linked to FTDP-17, a familial tauopathy. These results support the further development of small-molecule Casp2 inhibitors to treat synaptic deficits in tauopathies.
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Affiliation(s)
- Gurpreet Singh
- Department of Medicinal Chemistry, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Peng Liu
- Department of Neurology, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katherine R. Yao
- Department of Neuroscience, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jessica M. Strasser
- Department of Medicinal Chemistry, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Chris Hlynialuk
- Department of Neurology, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kailee Leinonen-Wright
- Department of Neurology, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Peter J. Teravskis
- Department of Neuroscience, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jessica M. Choquette
- Department of Neuroscience, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Junaid Ikramuddin
- Department of Neuroscience, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Merlin Bresinsky
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Kathryn M. Nelson
- Department of Medicinal Chemistry, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Dezhi Liao
- Department of Neuroscience, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Karen H. Ashe
- Department of Neurology, The University of Minnesota, Minneapolis, Minnesota 55455, United States
- Veterans Administration Medical Center, GRECC, Minneapolis, Minnesota 55417, United States
| | - Michael A. Walters
- Department of Medicinal Chemistry, The University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Steffen Pockes
- Department of Medicinal Chemistry, The University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department of Neurology, The University of Minnesota, Minneapolis, Minnesota 55455, United States
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
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19
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Mees I, Li S, Beauchamp LC, Barnham KJ, Dutschmann M, Hannan AJ, Renoir T. Loss-of-function and gain-of-function studies refute the hypothesis that tau protein is causally involved in the pathogenesis of Huntington's disease. Hum Mol Genet 2022; 31:1997-2009. [PMID: 34999772 DOI: 10.1093/hmg/ddac001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/17/2021] [Accepted: 01/04/2022] [Indexed: 11/15/2022] Open
Abstract
Tau is a microtubule-associated protein, whose abnormal phosphorylation and deposition in the brain characterizes a range of neurodegenerative diseases called tauopathies. Recent clinical (post-mortem) and pre-clinical evidence suggests that Huntington's disease (HD), an autosomal dominant neurodegenerative disorder, could be considered as a tauopathy. Studies have found the presence of hyperphosphorylated tau, altered tau isoform ratio and aggregated tau in HD brains. However, little is known about the implication of tau in the development of HD pathophysiology, which includes motor, cognitive and affective symptoms. To shine a light on the involvement of tau in HD, our present study aimed at (i) knocking out tau expression and (ii) expressing a transgene encoding mutant human tau in the R6/1 mouse model of HD. We hypothesized that expression of the mutant human tau transgene in HD mice would worsen the HD phenotype, while knocking out endogenous mouse tau in HD mice would improve some behavioural deficits display by HD mice. Our data suggests that neither the expression of a tau transgene nor the ablation of tau expression impacted the progression of the HD motor, cognitive and affective phenotypes. Supporting these behavioural findings, we also found that modulating tau expression had no effect on brain weights in HD mice. We also report that expression of the tau transgene increased the weight of WT and HD male mice, whereas tau ablation increased the weight of HD females only. Together, our results indicate that tau might not be as important in regulating the progression of HD symptomatology.
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Affiliation(s)
- Isaline Mees
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia
| | - Shanshan Li
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia
| | - Leah C Beauchamp
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia.,Melbourne Dementia Research Centre, University of Melbourne, Australia.,Department of Pharmacology and Therapeutics, University of Melbourne, Australia
| | - Kevin J Barnham
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia.,Melbourne Dementia Research Centre, University of Melbourne, Australia.,Department of Pharmacology and Therapeutics, University of Melbourne, Australia
| | - Mathias Dutschmann
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
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20
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Vogels T, Vargová G, Brezováková V, Quint WH, Hromádka T. Viral Delivery of Non-Mutated Human Truncated Tau to Neurons Recapitulates Key Features of Human Tauopathy in Wild-Type Mice. J Alzheimers Dis 2021; 77:551-568. [PMID: 32675411 DOI: 10.3233/jad-200047] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Neuronal accumulation of hyperphosphorylated and truncated tau aggregates is one of the major defining factors and key drivers of neurodegeneration in Alzheimer's disease and other tauopathies. OBJECTIVE We developed an AAV-induced model of tauopathy mediated by human truncated tau protein without familial frontotemporal dementia-related mutations to study tau propagation and the functional consequences of tau pathology. METHODS We performed targeted transductions of the hippocampus or entorhinal cortex in adult mice followed by histological analysis to study the progression of hippocampal tau pathology and tau spreading. We performed behavioral analysis of mice with AAV-induced hippocampal tau pathology. RESULTS AAV-induced hippocampal tau pathology was characterized by tau hyperphosphorylation (AT8 positivity), sarkosyl insolubility, and the presence of neurofibrillary tangles. AAV-induced tau pathology was associated with microgliosis and hypertrophic astrocytes in the absence of cognitive deficits. Additionally, the co-expression of mCherry fluorescent protein and human truncated tau enabled us to detect both local spreading of human tau and spreading from the entorhinal cortex to the synaptically connected dentate gyrus. CONCLUSION Targeted delivery of AAV with truncated tau protein into subcortical and cortical structures of mammalian brains represents an efficient approach for creating temporally and spatially well-defined tau pathology suitable for in vivo studies of tau propagation and neuronal circuit deficits in Alzheimer's disease.
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Affiliation(s)
- Thomas Vogels
- Axon Neuroscience R & D Services SE, Bratislava, Slovakia
| | - Gréta Vargová
- Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia
| | | | | | - Tomáš Hromádka
- Axon Neuroscience R & D Services SE, Bratislava, Slovakia.,Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia
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21
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Liu P, Ashe KH. The molecular implications of a caspase-2-mediated site-specific tau cleavage in tauopathies. Neural Regen Res 2021; 16:1774-1775. [PMID: 33510072 PMCID: PMC8328769 DOI: 10.4103/1673-5374.306073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Peng Liu
- Department of Neurology; N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, USA
| | - Karen H Ashe
- Department of Neurology; Department of Neuroscience; N. Bud Grossman Center for Memory Research and Care, University of Minnesota; Geriatric Research, Education, and Clinical Centers, Veterans Affairs Medical Center, Minneapolis, MN, USA
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22
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Masnata M, Salem S, de Rus Jacquet A, Anwer M, Cicchetti F. Targeting Tau to Treat Clinical Features of Huntington's Disease. Front Neurol 2020; 11:580732. [PMID: 33329322 PMCID: PMC7710872 DOI: 10.3389/fneur.2020.580732] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/17/2020] [Indexed: 12/16/2022] Open
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder characterized by severe motor, cognitive and psychiatric impairments. While motor deficits often confirm diagnosis, cognitive dysfunctions usually manifest early in the disease process and are consistently ranked among the leading factors that impact the patients' quality of life. The genetic component of HD, a mutation in the huntingtin (HTT) gene, is traditionally presented as the main contributor to disease pathology. However, accumulating evidence suggests the implication of the microtubule-associated tau protein to the pathogenesis and therefore, proposes an alternative conceptual framework where tau and mutant huntingtin (mHTT) act conjointly to drive neurodegeneration and cognitive dysfunction. This perspective on disease etiology offers new avenues to design therapeutic interventions and could leverage decades of research on Alzheimer's disease (AD) and other tauopathies to rapidly advance drug discovery. In this mini review, we examine the breadth of tau-targeting treatments currently tested in the preclinical and clinical settings for AD and other tauopathies, and discuss the potential application of these strategies to HD.
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Affiliation(s)
- Maria Masnata
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada
| | - Shireen Salem
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada
| | - Aurelie de Rus Jacquet
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada
| | - Mehwish Anwer
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada
| | - Francesca Cicchetti
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Québec, QC, Canada.,Département de Psychiatrie & Neurosciences, Université Laval, Québec, QC, Canada.,Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada
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23
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Lontay B, Kiss A, Virág L, Tar K. How Do Post-Translational Modifications Influence the Pathomechanistic Landscape of Huntington's Disease? A Comprehensive Review. Int J Mol Sci 2020; 21:ijms21124282. [PMID: 32560122 PMCID: PMC7349273 DOI: 10.3390/ijms21124282] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/11/2020] [Accepted: 06/13/2020] [Indexed: 12/15/2022] Open
Abstract
Huntington’s disease (HD) is an autosomal dominant inherited neurodegenerative disorder characterized by the loss of motor control and cognitive ability, which eventually leads to death. The mutant huntingtin protein (HTT) exhibits an expansion of a polyglutamine repeat. The mechanism of pathogenesis is still not fully characterized; however, evidence suggests that post-translational modifications (PTMs) of HTT and upstream and downstream proteins of neuronal signaling pathways are involved. The determination and characterization of PTMs are essential to understand the mechanisms at work in HD, to define possible therapeutic targets better, and to challenge the scientific community to develop new approaches and methods. The discovery and characterization of a panoply of PTMs in HTT aggregation and cellular events in HD will bring us closer to understanding how the expression of mutant polyglutamine-containing HTT affects cellular homeostasis that leads to the perturbation of cell functions, neurotoxicity, and finally, cell death. Hence, here we review the current knowledge on recently identified PTMs of HD-related proteins and their pathophysiological relevance in the formation of abnormal protein aggregates, proteolytic dysfunction, and alterations of mitochondrial and metabolic pathways, neuroinflammatory regulation, excitotoxicity, and abnormal regulation of gene expression.
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Affiliation(s)
- Beata Lontay
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (B.L.); (A.K.); (L.V.)
| | - Andrea Kiss
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (B.L.); (A.K.); (L.V.)
| | - László Virág
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (B.L.); (A.K.); (L.V.)
- MTA-DE Cell Biology and Signaling Research Group, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Krisztina Tar
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (B.L.); (A.K.); (L.V.)
- Correspondence: ; Tel.: +36-52-412345
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24
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Sladky VC, Villunger A. Uncovering the PIDDosome and caspase-2 as regulators of organogenesis and cellular differentiation. Cell Death Differ 2020; 27:2037-2047. [PMID: 32415279 PMCID: PMC7308375 DOI: 10.1038/s41418-020-0556-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/24/2020] [Accepted: 04/28/2020] [Indexed: 02/08/2023] Open
Abstract
The PIDDosome is a multiprotein complex that drives activation of caspase-2, an endopeptidase originally implicated in apoptosis. Yet, unlike other caspases involved in cell death and inflammation, caspase-2 seems to exert additional versatile functions unrelated to cell death. These emerging roles range from control of transcription factor activity to ploidy surveillance. Thus, caspase-2 and the PIDDosome act as a critical regulatory unit controlling cellular differentiation processes during organogenesis and regeneration. These newly established functions of the PIDDosome and its downstream effector render its components attractive targets for drug-development aiming to prevent fatty liver diseases, neurodegenerative disorders or osteoporosis. ![]()
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Affiliation(s)
- Valentina C Sladky
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Andreas Villunger
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria. .,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, 1090, Vienna, Austria. .,CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090, Vienna, Austria.
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25
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Teravskis PJ, Ashe KH, Liao D. The Accumulation of Tau in Postsynaptic Structures: A Common Feature in Multiple Neurodegenerative Diseases? Neuroscientist 2020; 26:503-520. [PMID: 32389059 DOI: 10.1177/1073858420916696] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Increasingly, research suggests that neurodegenerative diseases and dementias are caused not by unique, solitary cellular mechanisms, but by multiple contributory mechanisms manifesting as heterogeneous clinical presentations. However, diverse neurodegenerative diseases also share common pathological hallmarks and cellular mechanisms. One such mechanism involves the redistribution of the microtubule associated protein tau from the axon into the somatodendritic compartment of neurons, followed by the mislocalization of tau into dendritic spines, resulting in postsynaptic functional deficits. Here we review various signaling pathways that trigger the redistribution of tau to the cell body and dendritic tree, and its mislocalization to dendritic spines. The convergence of multiple pathways in different disease models onto this final common pathway suggests that it may be an attractive pathway to target for developing new treatments for neurodegenerative diseases.
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Affiliation(s)
- Peter J Teravskis
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA.,University of Minnesota Medical School, Minneapolis, MN, USA
| | - Karen H Ashe
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA.,N. Budd Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, USA.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA.,Geriatric Research Education and Clinical Center, Veterans Affairs Medical Center, Minneapolis, MN, USA
| | - Dezhi Liao
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
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26
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A soluble truncated tau species related to cognitive dysfunction is elevated in the brain of cognitively impaired human individuals. Sci Rep 2020; 10:3869. [PMID: 32123248 PMCID: PMC7052165 DOI: 10.1038/s41598-020-60777-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 02/12/2020] [Indexed: 11/13/2022] Open
Abstract
Neurofibrillary tangles are a pathological hallmark of Alzheimer’s disease, and their levels correlate with the severity of cognitive dysfunction in humans. However, experimental evidence suggests that soluble tau species cause cognitive deficits and memory impairment. Our recent study suggests that caspase-2 (Casp2)-catalyzed tau cleavage at aspartate 314 mediates synaptic dysfunction and memory impairment in mouse and cellular models of neurodegenerative disorders. Δtau314, the C-terminally-truncated cleavage products, are soluble and present in human brain. In addition, levels of Δtau314 proteins are elevated in the brain of the cognitively impaired individuals compared to the cognitively normal individuals, indicating a possible role for Δtau314 proteins in cognitive deterioration. Here we show that (1) Δtau314 proteins are present in the inferior temporal gyrus of human brains; (2) Δtau314 proteins are generated from all six tau splicing isoforms, (3) levels of both Casp2 and Δtau314 proteins are elevated in cognitively impaired individuals compared to cognitively normal individuals, and (4) levels of Δtau314 proteins show a modest predictive value for dementia. These findings advance our understanding of the characteristics of Δtau314 proteins and their relevance to cognitive dysfunction and shed light on the contribution of Casp2-mediated Δtau314 production to cognitive deterioration.
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27
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Kalabova D, Filandr F, Alblova M, Petrvalska O, Horvath M, Man P, Obsil T, Obsilova V. 14-3-3 protein binding blocks the dimerization interface of caspase-2. FEBS J 2020; 287:3494-3510. [PMID: 31961068 DOI: 10.1111/febs.15215] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 12/19/2019] [Accepted: 01/15/2020] [Indexed: 11/30/2022]
Abstract
Among all species, caspase-2 (C2) is the most evolutionarily conserved caspase required for effective initiation of apoptosis following death stimuli. C2 is activated through dimerization and autoproteolytic cleavage and inhibited through phosphorylation at Ser139 and Ser164 , within the linker between the caspase recruitment and p19 domains of the zymogen, followed by association with the adaptor protein 14-3-3, which maintains C2 in its immature form procaspase (proC2). However, the mechanism of 14-3-3-dependent inhibition of C2 activation remains unclear. Here, we report the structural characterization of the complex between proC2 and 14-3-3 by hydrogen/deuterium mass spectrometry and protein crystallography to determine the molecular basis for 14-3-3-mediated inhibition of C2 activation. Our data reveal that the 14-3-3 dimer interacts with proC2 not only through ligand-binding grooves but also through other regions outside the central channel, thus explaining the isoform-dependent specificity of 14-3-3 protein binding to proC2 and the substantially higher binding affinity of 14-3-3 protein to proC2 than to the doubly phosphorylated peptide. The formation of the complex between 14-3-3 protein and proC2 does not induce any large conformational change in proC2. Furthermore, 14-3-3 protein interacts with and masks both the nuclear localization sequence and the C-terminal region of the p12 domain of proC2 through transient interactions in which both the p19 and p12 domains of proC2 are not firmly docked onto the surface of 14-3-3. This masked region of p12 domain is involved in C2 dimerization. Therefore, 14-3-3 protein likely inhibits proC2 activation by blocking its dimerization surface. DATABASES: Structural data are available in the Protein Data Bank under the accession numbers 6SAD and 6S9K.
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Affiliation(s)
- Dana Kalabova
- Division BIOCEV, Department of Structural Biology of Signaling Proteins, Institute of Physiology of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Frantisek Filandr
- Division BIOCEV, Institute of Microbiology of the Czech Academy of Sciences, Vestec, Czech Republic.,Department of Biochemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Miroslava Alblova
- Division BIOCEV, Department of Structural Biology of Signaling Proteins, Institute of Physiology of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Olivia Petrvalska
- Division BIOCEV, Department of Structural Biology of Signaling Proteins, Institute of Physiology of the Czech Academy of Sciences, Vestec, Czech Republic.,Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Matej Horvath
- Division BIOCEV, Department of Structural Biology of Signaling Proteins, Institute of Physiology of the Czech Academy of Sciences, Vestec, Czech Republic.,Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Petr Man
- Division BIOCEV, Institute of Microbiology of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Tomas Obsil
- Division BIOCEV, Department of Structural Biology of Signaling Proteins, Institute of Physiology of the Czech Academy of Sciences, Vestec, Czech Republic.,Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Veronika Obsilova
- Division BIOCEV, Department of Structural Biology of Signaling Proteins, Institute of Physiology of the Czech Academy of Sciences, Vestec, Czech Republic
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28
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Fernández-Nogales M, Lucas JJ. Altered Levels and Isoforms of Tau and Nuclear Membrane Invaginations in Huntington's Disease. Front Cell Neurosci 2020; 13:574. [PMID: 32009905 PMCID: PMC6978886 DOI: 10.3389/fncel.2019.00574] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/12/2019] [Indexed: 12/13/2022] Open
Abstract
Since the early reports of neurofibrillary Tau pathology in brains of some Huntington’s disease (HD) patients, mounting evidence of multiple alterations of Tau in HD brain tissue has emerged in recent years. Such Tau alterations range from increased total levels, imbalance of isoforms generated by alternative splicing (increased 4R-/3R-Tau ratio) or by post-translational modifications such as hyperphosphorylation or truncation. Besides, the detection in HD brains of a new Tau histopathological hallmark known as Tau nuclear rods (TNRs) or Tau-positive nuclear indentations (TNIs) led to propose HD as a secondary Tauopathy. After their discovery in HD brains, TNIs have also been reported in hippocampal neurons of early Braak stage AD cases and in frontal and temporal cortical neurons of FTD-MAPT cases due to the intronic IVS10+16 mutation in the Tau gene (MAPT) which results in an increased 4R-/3R-Tau ratio similar to that observed in HD. TNIs are likely pathogenic for contributing to the disturbed nucleocytoplasmic transport observed in HD. A key question is whether correction of any of the mentioned Tau alterations might have positive therapeutic implications for HD. The beneficial effect of decreasing Tau expression in HD mouse models clearly implicates Tau in HD pathogenesis. Such beneficial effect might be exerted by diminishing the excess total levels of Tau or specifically by diminishing the excess 4R-Tau, as well as any of their downstream effects. In any case, since gene silencing drugs are under development to attenuate both Huntingtin (HTT) expression for HD and MAPT expression for FTD-MAPT, it is conceivable that the combined therapy in HD patients might be more effective than HTT silencing alone.
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Affiliation(s)
| | - José J Lucas
- Centro de Biología Molecular Severo Ochoa (CBMSO)(CSIC-UAM), Madrid, Spain.,Networking Research Center on Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
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