1
|
Li W, Li HL, Wang JZ, Liu R, Wang X. Abnormal protein post-translational modifications induces aggregation and abnormal deposition of protein, mediating neurodegenerative diseases. Cell Biosci 2024; 14:22. [PMID: 38347638 PMCID: PMC10863199 DOI: 10.1186/s13578-023-01189-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 12/23/2023] [Indexed: 02/15/2024] Open
Abstract
Protein post-translational modifications (PPTMs) refer to a series of chemical modifications that occur after the synthesis of protein. Proteins undergo different modifications such as phosphorylation, acetylation, ubiquitination, and so on. These modifications can alter the protein's structure, function, and interaction, thereby regulating its biological activity. In neurodegenerative diseases, several proteins undergo abnormal post-translational modifications, which leads to aggregation and abnormal deposition of protein, thus resulting in neuronal death and related diseases. For example, the main pathological features of Alzheimer's disease are the aggregation of beta-amyloid protein and abnormal phosphorylation of tau protein. The abnormal ubiquitination and loss of α-synuclein are related to the onset of Parkinson's disease. Other neurodegenerative diseases such as Huntington's disease, amyotrophic lateral sclerosis, and so on are also connected with abnormal PPTMs. Therefore, studying the abnormal PPTMs in neurodegenerative diseases is critical for understanding the mechanism of these diseases and the development of significant therapeutic strategies. This work reviews the implications of PPTMs in neurodegenerative diseases and discusses the relevant therapeutic strategies.
Collapse
Affiliation(s)
- Wei Li
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hong-Lian Li
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jian-Zhi Wang
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, JS, China
| | - Rong Liu
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Shenzhen Huazhong University of Science and Technology Research Institute, Wuhan, China.
| | - Xiaochuan Wang
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, JS, China.
- Shenzhen Huazhong University of Science and Technology Research Institute, Wuhan, China.
| |
Collapse
|
2
|
Yadikar H, Johnson C, Pafundi N, Nguyen L, Kurup M, Torres I, Al-Enezy A, Yang Z, Yost R, Kobeissy FH, Wang KKW. Neurobiochemical, Peptidomic, and Bioinformatic Approaches to Characterize Tauopathy Peptidome Biomarker Candidates in Experimental Mouse Model of Traumatic Brain Injury. Mol Neurobiol 2023; 60:2295-2319. [PMID: 36635478 DOI: 10.1007/s12035-022-03165-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 12/10/2022] [Indexed: 01/14/2023]
Abstract
Traumatic brain injury (TBI) is a multidimensional damage, and currently, no FDA-approved medicine is available. Multiple pathways in the cell are triggered through a head injury (e.g., calpain and caspase activation), which truncate tau and generate variable fragment sizes (MW 400-45,000 K). In this study, we used an open-head TBI mouse model generated by controlled cortical impact (CCI) and collected ipsilateral (IC) and contralateral (CC) mice htau brain cortices at one (D1) three (D3), and seven (D7) days post-injury. We implemented immunological (antibody-based detection) and peptidomic approaches (nano-reversed-phase liquid chromatography/tandem mass spectrometry) to investigate proteolytic tau peptidome (low molecular weight (LMW) < 10 K)) and pathological phosphorylation sites (high-molecular-weight (HMW); > 10 K) derived from CCI-TBI animal models. Our immunoblotting analysis verified tau hyperphosphorylation, HMW, and HMW breakdown products (HMW-BDP) formation of tau (e.g., pSer202, pThr181, pThr231, pSer396, and pSer404), following CCI-TBI. Peptidomic data revealed unique sequences of injury-dependent proteolytic peptides generated from human tau protein. Among the N-terminal tau peptides, EIPEGTTAEEAGIGDTPSLEDEAAGHVTQA (a.a. 96-125) and AQPHTEIPEGTTAEEAGIGDTPSLEDEAAGHVTQARM (a.a. 91-127). Examples of tau C-terminal peptides identified include NVSSTGSIDMVDSPQLATLADEVSASLAKQGL (a.a. 410-441) and QLATLADEVSASLAKQGL (a.a. 424-441). Our peptidomic bioinformatic tools showed the association of proteases, such as CAPN1, CAPN2, and CTSL; CASP1, MMP7, and MMP9; and ELANE, GZMA, and MEP1A, in CCI-TBI tau peptidome. In clinical trials for novel TBI treatments, it might be useful to monitor a subset of tau peptidome as targets for biomarker utility and use them for a "theranostic" approach.
Collapse
Affiliation(s)
- Hamad Yadikar
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait.
| | - Connor Johnson
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Niko Pafundi
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Lynn Nguyen
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Milin Kurup
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Isabel Torres
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Albandery Al-Enezy
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Zhihui Yang
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Richard Yost
- Department of Chemistry, Chemistry Laboratory Building, University of Florida, Gainesville, FL, 32611, USA
| | - Firas H Kobeissy
- Program for Neurotrauma, Neuroproteomics & Biomarkers Research, Departments of Emergency Medicine, Psychiatry, Neuroscience and Chemistry, University of Florida, Gainesville, FL, USA. .,Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon. .,Morehouse School of Medicine, Department of Neurobiology, Center for Neurotrauma, Multiomics & Biomarkers (CNMB), 720 Westview Dr. SW, Atlanta, GA, 30310, USA.
| | - Kevin K W Wang
- Program for Neurotrauma, Neuroproteomics & Biomarkers Research, Departments of Emergency Medicine, Psychiatry, Neuroscience and Chemistry, University of Florida, Gainesville, FL, USA. .,Morehouse School of Medicine, Department of Neurobiology, Center for Neurotrauma, Multiomics & Biomarkers (CNMB), 720 Westview Dr. SW, Atlanta, GA, 30310, USA. .,Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, 32608, USA.
| |
Collapse
|
3
|
Lynch M, Pham W, Sinclair B, O’Brien TJ, Law M, Vivash L. Perivascular spaces as a potential biomarker of Alzheimer's disease. Front Neurosci 2022; 16:1021131. [PMID: 36330347 PMCID: PMC9623161 DOI: 10.3389/fnins.2022.1021131] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/23/2022] [Indexed: 07/20/2023] Open
Abstract
Alzheimer's disease (AD) is a highly damaging disease that affects one's cognition and memory and presents an increasing societal and economic burden globally. Considerable research has gone into understanding AD; however, there is still a lack of effective biomarkers that aid in early diagnosis and intervention. The recent discovery of the glymphatic system and associated Perivascular Spaces (PVS) has led to the theory that enlarged PVS (ePVS) may be an indicator of AD progression and act as an early diagnostic marker. Visible on Magnetic Resonance Imaging (MRI), PVS appear to enlarge when known biomarkers of AD, amyloid-β and tau, accumulate. The central goal of ePVS and AD research is to determine when ePVS occurs in AD progression and if ePVS are causal or epiphenomena. Furthermore, if ePVS are indeed causative, interventions promoting glymphatic clearance are an attractive target for research. However, it is necessary first to ascertain where on the pathological progression of AD ePVS occurs. This review aims to examine the knowledge gap that exists in understanding the contribution of ePVS to AD. It is essential to understand whether ePVS in the brain correlate with increased regional tau distribution and global or regional Amyloid-β distribution and to determine if these spaces increase proportionally over time as individuals experience neurodegeneration. This review demonstrates that ePVS are associated with reduced glymphatic clearance and that this reduced clearance is associated with an increase in amyloid-β. However, it is not yet understood if ePVS are the outcome or driver of protein accumulation. Further, it is not yet clear if ePVS volume and number change longitudinally. Ultimately, it is vital to determine early diagnostic criteria and early interventions for AD to ease the burden it presents to the world; ePVS may be able to fulfill this role and therefore merit further research.
Collapse
Affiliation(s)
- Miranda Lynch
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - William Pham
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Benjamin Sinclair
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurology, Alfred Hospital, Melbourne, VIC, Australia
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
| | - Terence J. O’Brien
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurology, Alfred Hospital, Melbourne, VIC, Australia
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
- Department of Neurology, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
| | - Meng Law
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Radiology, Alfred Health, Melbourne, VIC, Australia
- Department of Electrical and Computer Systems Engineering, Monash University, Melbourne, VIC, Australia
| | - Lucy Vivash
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurology, Alfred Hospital, Melbourne, VIC, Australia
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
- Department of Neurology, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
4
|
La Barbera L, Mauri E, D’Amelio M, Gori M. Functionalization strategies of polymeric nanoparticles for drug delivery in Alzheimer’s disease: Current trends and future perspectives. Front Neurosci 2022; 16:939855. [PMID: 35992936 PMCID: PMC9387393 DOI: 10.3389/fnins.2022.939855] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/11/2022] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD), the most common form of dementia, is a progressive and multifactorial neurodegenerative disorder whose primary causes are mostly unknown. Due to the increase in life expectancy of world population, including developing countries, AD, whose incidence rises dramatically with age, is at the forefront among neurodegenerative diseases. Moreover, a definitive cure is not yet within reach, imposing substantial medical and public health burdens at every latitude. Therefore, the effort to devise novel and effective therapeutic strategies is still of paramount importance. Genetic, functional, structural and biochemical studies all indicate that new and efficacious drug delivery strategies interfere at different levels with various cellular and molecular targets. Over the last few decades, therapeutic development of nanomedicine at preclinical stage has shown to progress at a fast pace, thus paving the way for its potential impact on human health in improving prevention, diagnosis, and treatment of age-related neurodegenerative disorders, including AD. Clinical translation of nano-based therapeutics, despite current limitations, may present important advantages and innovation to be exploited in the neuroscience field as well. In this state-of-the-art review article, we present the most promising applications of polymeric nanoparticle-mediated drug delivery for bypassing the blood-brain barrier of AD preclinical models and boost pharmacological safety and efficacy. In particular, novel strategic chemical functionalization of polymeric nanocarriers that could be successfully employed for treating AD are thoroughly described. Emphasis is also placed on nanotheranostics as both potential therapeutic and diagnostic tool for targeted treatments. Our review highlights the emerging role of nanomedicine in the management of AD, providing the readers with an overview of the nanostrategies currently available to develop future therapeutic applications against this chronic neurodegenerative disease.
Collapse
Affiliation(s)
- Livia La Barbera
- Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
- Santa Lucia Foundation, IRCSS, Rome, Italy
| | - Emanuele Mauri
- Department of Engineering, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Marcello D’Amelio
- Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
- Santa Lucia Foundation, IRCSS, Rome, Italy
| | - Manuele Gori
- Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
- Institute of Biochemistry and Cell Biology (IBBC) - National Research Council (CNR), Rome, Italy
- *Correspondence: Manuele Gori,
| |
Collapse
|
5
|
Mittal A, Sharma R, Sardana S, Goyal PK, Piplani M, Pandey A. A Systematic Review of updated mechanistic insights towards Alzheimer's disease. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2022; 22:CNSNDDT-EPUB-123335. [PMID: 35538829 DOI: 10.2174/1871527321666220510144127] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/19/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND PURPOSE Alzheimer's disease (AD) is a degenerative neurological disorder that impairs memory, cognitive abilities, and the ability to do even most everyday activities. This neurodegenerative disease is growing increasingly common as the world's population ages. Here we reviewed some of the key findings that have shown the function of Aβ peptide, oxidative stress, free radical damage Triggering Receptors Expressed on Myeloid Cells 2 (TREM2), Nitric Oxide (NO), and gut microbiota in the aetiology of AD. METHODOLOGY The potentially relevant online medical databases, namely, PubMed, Scopus, Google Scholar, Cochrane Library, and JSTOR were exhaustively researched. In addition, the data reported in the present study were primarily intervened on the basis of the timeline selected from 1 January 2000 to 31 October 2021. The whole framework was designed substantially based on key terms and studies selected by virtue of their relevance to our investigations. RESULTS Findings suggested that channels of free radicals, such as transition metal accumulation, and genetic factors are mainly accountable for the redox imbalance that assist to understand better the pathogenesis of AD and incorporate new therapeutic approaches. Moreover, TREM2 might elicit a protective function for microglia in AD. NO causes an increase in oxidative stress and mitochondrial damage, compromising cellular integrity and viability. The study also explored that the gut and CNS communicate with one another and that regulating gut commensal flora might be a viable therapeutic for neurodegenerative illnesses like AD. CONCLUSION There are presently no viable therapies for Alzheimer's disease, but recent breakthroughs in our knowledge of the disease's pathophysiology may aid in the discovery of prospective therapeutic targets.
Collapse
Affiliation(s)
- Arun Mittal
- Amity University Haryana, Manesar, Gurgaon, Haryana
| | | | | | | | - Mona Piplani
- Maharaja Agarsen University, Solan, Himachal Pardesh
| | - Anima Pandey
- Birla Institute of Technology, Mesra, Ranchi, Jharkhand
| |
Collapse
|
6
|
Theofilas P, Piergies AMH, Oh I, Lee YB, Li SH, Pereira FL, Petersen C, Ehrenberg AJ, Eser RA, Ambrose AJ, Chin B, Yang T, Khan S, Ng R, Spina S, Seeley WW, Miller BL, Arkin MR, Grinberg LT. Caspase-6-cleaved tau is relevant in Alzheimer's disease and marginal in four-repeat tauopathies: diagnostic and therapeutic implications. Neuropathol Appl Neurobiol 2022; 48:e12819. [PMID: 35508761 PMCID: PMC9472770 DOI: 10.1111/nan.12819] [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: 01/22/2021] [Revised: 03/22/2022] [Accepted: 03/26/2022] [Indexed: 11/27/2022]
Abstract
AIM Tau truncation (tr-tau) by active caspase-6 (aCasp-6) generates tau fragments that may be toxic. Yet, the relationship between aCasp-6, different forms of tr-tau, and hyperphosphorylated tau (p-tau) accumulation in human brains with Alzheimer's disease (AD) and other tauopathies remains unclear. METHODS We generated two neoepitope monoclonal antibodies against tr-tau sites (D402 and D13) targeted by aCasp-6. Then, we used 5-plex immunofluorescence to quantify the neuronal and astroglial burden of aCasp-6, tr-tau, p-tau, and their co-occurrence in healthy controls, AD, and primary tauopathies. RESULTS Casp-6 activation was strongest in AD and Pick's disease (PiD), but almost absent in 4-repeat (4R) tauopathies. In neurons, the tr-tau burden was much more abundant in AD and PiD than in 4R tauopathies and disproportionally higher when normalizing by p-tau pathology. Tr-tau astrogliopathy was detected in low numbers in 4R tauopathies. Unexpectedly, about half of tr-tau positive neurons in AD and PiD lacked p-tau aggregates, a finding we confirmed using several p-tau antibodies. CONCLUSIONS Early modulation of aCasp-6 to reduce tr-tau pathology is a promising therapeutic strategy for AD and PiD, but is unlikely to benefit 4R tauopathies. The large percentage of tr-tau-positive neurons lacking p-tau suggests that many vulnerable neurons to tau pathology go undetected when using conventional p-tau antibodies. Therapeutic strategies against tr-tau pathology could be necessary to modulate the extent of tau abnormalities in AD. The disproportionally higher burden of tr-tau in AD and PiD supports the development of biofluid biomarkers against tr-tau to detect AD and PiD and differentiate them from 4R tauopathies at a patient level.
Collapse
Affiliation(s)
- Panos Theofilas
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Antonia M H Piergies
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Ian Oh
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Yoo Bin Lee
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Song Hua Li
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Felipe L Pereira
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Cathrine Petersen
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Alexander J Ehrenberg
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Rana A Eser
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Andrew J Ambrose
- Department of Pharmaceutical Chemistry and Small Molecule Discovery Center, UCSF, San Francisco, CA, USA
| | | | | | - Shireen Khan
- ChemPartner San Francisco, South San Francisco, CA, USA
| | - Raymond Ng
- ChemPartner San Francisco, South San Francisco, CA, USA
| | - Salvatore Spina
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA
| | - Willian W Seeley
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA.,Department of Pathology, University of California, San Francisco, San Francisco, CA, USA
| | - Bruce L Miller
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA.,Global Brain Health Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Michelle R Arkin
- Department of Pharmaceutical Chemistry and Small Molecule Discovery Center, UCSF, San Francisco, CA, USA
| | - Lea T Grinberg
- Memory and Aging Center, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA, USA.,Department of Pathology, University of California, San Francisco, San Francisco, CA, USA.,Global Brain Health Institute, University of California, San Francisco, San Francisco, CA, USA.,Department of Pathology, University of Sao Paulo Medical School, Sao Paulo, Brazil
| |
Collapse
|
7
|
Amro Z, Yool AJ, Collins-Praino LE. The potential role of glial cells in driving the prion-like transcellular propagation of tau in tauopathies. Brain Behav Immun Health 2021; 14:100242. [PMID: 34589757 PMCID: PMC8474563 DOI: 10.1016/j.bbih.2021.100242] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 03/11/2021] [Indexed: 02/08/2023] Open
Abstract
Dementia is one of the leading causes of death worldwide, with tauopathies, a class of diseases defined by pathology associated with the microtubule-enriched protein, tau, as the major contributor. Although tauopathies, such as Alzheimer's disease and Frontotemporal dementia, are common amongst the ageing population, current effective treatment options are scarce, primarily due to the incomplete understanding of disease pathogenesis. The mechanisms via which aggregated forms of tau are able to propagate from one anatomical area to another to cause disease spread and progression is yet unknown. The prion-like hypothesis of tau propagation proposes that tau can propagate along neighbouring anatomical areas in a similar manner to prion proteins in prion diseases, such as Creutzfeldt-Jacob disease. This hypothesis has been supported by a plethora of studies that note the ability of tau to be actively secreted by neurons, propagated and internalised by neighbouring neuronal cells, causing disease spread. Surfacing research suggests a role of reactive astrocytes and microglia in early pre-clinical stages of tauopathy through their inflammatory actions. Furthermore, both glial types are able to internalise and secrete tau from the extracellular space, suggesting a potential role in tau propagation; although understanding the physiological mechanisms by which this can occur remains poorly understood. This review will discuss the current literature around the prion-like propagation of tau, with particular emphasis on glial-mediated neuroinflammation and the contribution it may play in this propagation process.
Collapse
Affiliation(s)
- Zein Amro
- Adelaide Medical School, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Andrea J Yool
- Adelaide Medical School, University of Adelaide, Adelaide, SA, 5005, Australia
| | | |
Collapse
|
8
|
Syntaxins 6 and 8 facilitate tau into secretory pathways. Biochem J 2021; 478:1471-1484. [PMID: 33769438 PMCID: PMC8057678 DOI: 10.1042/bcj20200664] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 03/17/2021] [Accepted: 03/26/2021] [Indexed: 12/04/2022]
Abstract
Tau pathology initiates in defined brain regions and is known to spread along neuronal connections as symptoms progress in Alzheimer's disease (AD) and other tauopathies. This spread requires the release of tau from donor cells, but the underlying molecular mechanisms remained unknown. Here, we established the interactome of the C-terminal tail region of tau and identified syntaxin 8 (STX8) as a mediator of tau release from cells. Similarly, we showed the syntaxin 6 (STX6), part of the same SNARE family as STX8 also facilitated tau release. STX6 was previously genetically linked to progressive supranuclear palsy (PSP), a tauopathy. Finally, we demonstrated that the transmembrane domain of STX6 is required and sufficient to mediate tau secretion. The differential role of STX6 and STX8 in alternative secretory pathways suggests the association of tau with different secretory processes. Taken together, both syntaxins, STX6 and STX8, may contribute to AD and PSP pathogenesis by mediating release of tau from cells and facilitating pathology spreading.
Collapse
|
9
|
Martínez-Maldonado A, Ontiveros-Torres MÁ, Harrington CR, Montiel-Sosa JF, Prandiz RGT, Bocanegra-López P, Sorsby-Vargas AM, Bravo-Muñoz M, Florán-Garduño B, Villanueva-Fierro I, Perry G, Garcés-Ramírez L, de la Cruz F, Martínez-Robles S, Pacheco-Herrero M, Luna-Muñoz J. Molecular Processing of Tau Protein in Progressive Supranuclear Palsy: Neuronal and Glial Degeneration. J Alzheimers Dis 2021; 79:1517-1531. [PMID: 33459640 PMCID: PMC7990452 DOI: 10.3233/jad-201139] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) and progressive supranuclear palsy (PSP) are examples of neurodegenerative diseases, characterized by abnormal tau inclusions, that are called tauopathies. AD is characterized by highly insoluble paired helical filaments (PHFs) composed of tau with abnormal post-translational modifications. PSP is a neurodegenerative disease with pathological and clinical heterogeneity. There are six tau isoforms expressed in the adult human brain, with repeated microtubule-binding domains of three (3R) or four (4R) repeats. In AD, the 4R:3R ratio is 1:1. In PSP, the 4R isoform predominates. The lesions in PSP brains contain phosphorylated tau aggregates in both neurons and glial cells. OBJECTIVE Our objective was to evaluate and compare the processing of pathological tau in PSP and AD. METHODS Double and triple immunofluorescent labeling with antibodies to specific post-translational tau modifications (phosphorylation, truncation, and conformational changes) and thiazin red (TR) staining were carried out and analyzed by confocal microscopy. RESULTS Our results showed that PSP was characterized by phosphorylated tau in neurofibrillary tangles (NFTs) and glial cells. Tau truncated at either Glu391 or Asp421 was not observed. Extracellular NFTs (eNFTs) and glial cells in PSP exhibited a strong affinity for TR in the absence of intact or phosphorylated tau. CONCLUSION Phosphorylated tau was as abundant in PSP as in AD. The development of eNFTs from both glial cells and neuronal bodies suggests that truncated tau species, different from those observed in AD, could be present in PSP. Additional studies on truncated tau within PSP lesions could improve our understanding of the pathological processing of tau and help identify a discriminatory biomarker for AD and PSP.
Collapse
Affiliation(s)
- Alejandra Martínez-Maldonado
- Departamento de Fisiología Biofísica y Neurociencias, CINVESTAV, México City, México
- Facultad de Ciencias de la Salud, Universidad Anáhuac México Norte, México
| | | | - Charles R. Harrington
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - José Francisco Montiel-Sosa
- National Dementia BioBank, Ciencias Biológicas, Facultad de Estudios Superiores, Cuautitlán, UNAM, Estado de México, México
| | | | | | | | - Marely Bravo-Muñoz
- National Dementia BioBank, Ciencias Biológicas, Facultad de Estudios Superiores, Cuautitlán, UNAM, Estado de México, México
| | | | | | - George Perry
- College of Sciences, University of Texas at San Antonio, San Antonio, TX, USA
| | - Linda Garcés-Ramírez
- Escuela Nacional de Ciencias Biológicas, Depto. Fisiología, Instituto Politécnico Nacional, CDMX, México
| | - Fidel de la Cruz
- Escuela Nacional de Ciencias Biológicas, Depto. Fisiología, Instituto Politécnico Nacional, CDMX, México
| | - Sandra Martínez-Robles
- National Dementia BioBank, Ciencias Biológicas, Facultad de Estudios Superiores, Cuautitlán, UNAM, Estado de México, México
| | - Mar Pacheco-Herrero
- Neuroscience Research Laboratory, Faculty of Health Sciences, Pontificia Universidad Catolica Madre y Maestra, Santiago de los Caballeros, República Dominicana
| | - José Luna-Muñoz
- National Dementia BioBank, Ciencias Biológicas, Facultad de Estudios Superiores, Cuautitlán, UNAM, Estado de México, México
- Banco Nacional de Cerebros-UNPHU, Universidad Nacional Pedro Henríquez Ureña, República Dominicana
| |
Collapse
|
10
|
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.
Collapse
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.
| |
Collapse
|
11
|
Luna-Viramontes NI, Campa-Córdoba BB, Ontiveros-Torres MÁ, Harrington CR, Villanueva-Fierro I, Guadarrama-Ortíz P, Garcés-Ramírez L, de la Cruz F, Hernandes-Alejandro M, Martínez-Robles S, González-Ballesteros E, Pacheco-Herrero M, Luna-Muñoz J. PHF-Core Tau as the Potential Initiating Event for Tau Pathology in Alzheimer's Disease. Front Cell Neurosci 2020; 14:247. [PMID: 33132840 PMCID: PMC7511711 DOI: 10.3389/fncel.2020.00247] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/15/2020] [Indexed: 11/13/2022] Open
Abstract
Worldwide, around 50 million people have dementia. Alzheimer's disease (AD) is the most common type of dementia and one of the major causes of disability and dependency among the elderly worldwide. Clinically, AD is characterized by impaired memory accompanied by other deficiencies in the cognitive domain. Neuritic plaques (NPs) and neurofibrillary tangles (NFTs) are histopathological lesions that define brains with AD. NFTs consist of abundant intracellular paired helical filaments (PHFs) whose main constituent is tau protein. Tau undergoes posttranslational changes including hyperphosphorylation and truncation, both of which favor conformational changes in the protein. The sequential pathological processing of tau is illustrated with the following specific markers: pT231, TG3, AT8, AT100, and Alz50. Two proteolysis sites for tau have been described-truncation at glutamate 391 and at aspartate 421-and which can be demonstrated by reactivity with the antibodies 423 and TauC-3, respectively. In this review, we describe the molecular changes in tau protein as pre-NFTs progress to extracellular NFTs and during which the formation of a minimal nucleus of the filament, as the PHF core, occurs. We also analyzed the PHF core as the initiator of PHFs and tau phosphorylation as a protective neuronal mechanism against the assembly of the PHF core.
Collapse
Affiliation(s)
- Nabil Itzi Luna-Viramontes
- National Dementia BioBank, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Departamento de Fisiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - B Berenice Campa-Córdoba
- National Dementia BioBank, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Departamento de Fisiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - Charles R Harrington
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | | | - Parménides Guadarrama-Ortíz
- Departamento de Neurocirugía, Centro Especializado en Neurocirugía y Neurociencias México, CENNM, CDMX, Mexico City, Mexico
| | - Linda Garcés-Ramírez
- Departamento de Fisiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Fidel de la Cruz
- Departamento de Fisiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Mario Hernandes-Alejandro
- Departamento de Bioingeniería, Unidad Profesional Interdisciplinaria de Biotecnología del Instituto Politécnico Nacional (UPIBI-IPN), Mexico City, México
| | - Sandra Martínez-Robles
- National Dementia BioBank, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Erik González-Ballesteros
- National Dementia BioBank, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mar Pacheco-Herrero
- Neuroscience Research Laboratory, Faculty of Health Sciences, Pontificia Universidad Catolica Madre y Maestra, Santiago de los Caballeros, Dominican Republic
| | - José Luna-Muñoz
- National Dementia BioBank, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores, Universidad Nacional Autónoma de México, Mexico City, Mexico
| |
Collapse
|
12
|
Gu J, Xu W, Jin N, Li L, Zhou Y, Chu D, Gong CX, Iqbal K, Liu F. Truncation of Tau selectively facilitates its pathological activities. J Biol Chem 2020; 295:13812-13828. [PMID: 32737201 DOI: 10.1074/jbc.ra120.012587] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 07/29/2020] [Indexed: 01/09/2023] Open
Abstract
Neurofibrillary tangles of abnormally hyperphosphorylated Tau are a hallmark of Alzheimer's disease (AD) and related tauopathies. Tau is truncated at multiple sites by various proteases in AD brain. Although many studies have reported the effect of truncation on the aggregation of Tau, these studies mostly employed highly artificial conditions, using heparin sulfate or arachidonic acid to induce aggregation. Here, we report for the first time the pathological activities of various truncations of Tau, including site-specific phosphorylation, self-aggregation, binding to hyperphosphorylated and oligomeric Tau isolated from AD brain tissue (AD O-Tau), and aggregation seeded by AD O-Tau. We found that deletion of the first 150 or 230 amino acids (aa) enhanced Tau's site-specific phosphorylation, self-aggregation, and binding to AD O-Tau and aggregation seeded by AD O-Tau, but deletion of the first 50 aa did not produce a significant effect. Deletion of the last 50 aa was found to modulate Tau's site-specific phosphorylation, promote its self-aggregation, and cause it to be captured by and aggregation seeded by AD O-Tau, whereas deletion of the last 20 aa had no such effects. Among the truncated Taus, Tau151-391 showed the highest pathological activities. AD O-Tau induced aggregation of Tau151-391 in vitro and in cultured cells. These findings suggest that the first 150 aa and the last 50 aa protect Tau from pathological characteristics and that their deletions facilitate pathological activities. Thus, inhibition of Tau truncation may represent a potential therapeutic approach to suppress Tau pathology in AD and related tauopathies.
Collapse
Affiliation(s)
- Jianlan Gu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA; Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Nantong University, Nantong, Jiangsu, China
| | - Wen Xu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA; Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Nantong University, Nantong, Jiangsu, China
| | - Nana Jin
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Nantong University, Nantong, Jiangsu, China
| | - Longfei Li
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA; Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Nantong University, Nantong, Jiangsu, China
| | - Yan Zhou
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA; Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Nantong University, Nantong, Jiangsu, China
| | - Dandan Chu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Nantong University, Nantong, Jiangsu, China
| | - Cheng-Xin Gong
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA
| | - Khalid Iqbal
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA
| | - Fei Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA.
| |
Collapse
|
13
|
Stevens CH, Guthrie NJ, van Roijen M, Halliday GM, Ooi L. Increased Tau Phosphorylation in Motor Neurons From Clinically Pure Sporadic Amyotrophic Lateral Sclerosis Patients. J Neuropathol Exp Neurol 2020; 78:605-614. [PMID: 31131395 DOI: 10.1093/jnen/nlz041] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of motor neurons. There is a pathological and genetic link between ALS and frontotemporal lobar degeneration (FTLD). Although FTLD is characterized by abnormal phosphorylated tau deposition, it is unknown whether tau is phosphorylated in ALS motor neurons. Therefore, this study assessed tau epitopes that are commonly phosphorylated in FTLD, including serine 396 (pS396), 214 (pS214), and 404 (pS404) in motor neurons from clinically pure sporadic ALS cases compared with controls. In ALS lower motor neurons, tau pS396 was observed in the nucleus or the nucleus and cytoplasm. In ALS upper motor neurons, tau pS396 was observed in the nucleus, cytoplasm, or both the nucleus and cytoplasm. Tau pS214 and pS404 was observed only in the cytoplasm of upper and lower motor neurons in ALS. The number of motor neurons (per mm2) positive for tau pS396 and pS214, but not pS404, was significantly increased in ALS. Furthermore, there was a significant loss of phosphorylated tau-negative motor neurons in ALS compared with controls. Together, our data identified a complex relationship between motor neurons positive for tau phosphorylated at specific residues and disease duration, suggesting that tau phosphorylation plays a role in ALS.
Collapse
Affiliation(s)
- Claire H Stevens
- School of Chemistry and Molecular Bioscience, University of Wollongong.,Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia
| | - Natalie J Guthrie
- School of Chemistry and Molecular Bioscience, University of Wollongong.,Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia
| | | | - Glenda M Halliday
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Camperdown, New South Wales, Australia
| | - Lezanne Ooi
- School of Chemistry and Molecular Bioscience, University of Wollongong.,Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia
| |
Collapse
|
14
|
Mixed Borrelia burgdorferi and Helicobacter pylori Biofilms in Morgellons Disease Dermatological Specimens. Healthcare (Basel) 2019; 7:healthcare7020070. [PMID: 31108976 PMCID: PMC6627092 DOI: 10.3390/healthcare7020070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/17/2019] [Accepted: 05/14/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Morgellons disease (MD) is a dermopathy that is associated with tick-borne illness. It is characterized by spontaneously developing skin lesions containing embedded or projecting filaments, and patients may also experience symptoms resembling those of Lyme disease (LD) including musculoskeletal, neurological and cardiovascular manifestations. Various species of Borrelia and co-infecting pathogens have been detected in body fluids and tissue specimens from MD patients. We sought to investigate the coexistence of Borrelia burgdorferi (Bb) and Helicobacter pylori (Hp) in skin specimens from MD subjects, and to characterize their association with mixed amyloid biofilm development. METHODS Testing for Bb and Hp was performed on dermatological specimens from 14 MD patients using tissue culture, immunohistochemical (IHC) staining, polymerase chain reaction (PCR) testing, fluorescent in situ hybridization (FISH) and confocal microscopy. Markers for amyloid and biofilm formation were investigated using histochemical and IHC staining. RESULTS Bb and Hp were detected in dermatological tissue taken from MD lesions. Bb and Hp tended to co-localize in foci within the epithelial tissue. Skin sections exhibiting foci of co-infecting Bb and Hp contained amyloid markers including β-amyloid protein, thioflavin and phosphorylated tau. The biofilm marker alginate was also found in the sections. CONCLUSIONS Mixed Bb and Hp biofilms containing β-amyloid and phosphorylated tau may play a role in the evolution of MD.
Collapse
|
15
|
Perez SE, Miguel JC, He B, Malek-Ahmadi M, Abrahamson EE, Ikonomovic MD, Lott I, Doran E, Alldred MJ, Ginsberg SD, Mufson EJ. Frontal cortex and striatal cellular and molecular pathobiology in individuals with Down syndrome with and without dementia. Acta Neuropathol 2019; 137:413-436. [PMID: 30734106 PMCID: PMC6541490 DOI: 10.1007/s00401-019-01965-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 01/18/2019] [Accepted: 01/22/2019] [Indexed: 02/06/2023]
Abstract
Although, by age 40, individuals with Down syndrome (DS) develop amyloid-β (Aβ) plaques and tau-containing neurofibrillary tangles (NFTs) linked to cognitive impairment in Alzheimer's disease (AD), not all people with DS develop dementia. Whether Aβ plaques and NFTs are associated with individuals with DS with (DSD +) and without dementia (DSD -) is under-investigated. Here, we applied quantitative immunocytochemistry and fluorescent procedures to characterize NFT pathology using antibodies specific for tau phosphorylation (pS422, AT8), truncation (TauC3, MN423), and conformational (Alz50, MC1) epitopes, as well as Aβ and its precursor protein (APP) to frontal cortex (FC) and striatal tissue from DSD + to DSD - cases. Expression profiling of single pS422 labeled FC layer V and VI neurons was also determined using laser capture microdissection and custom-designed microarray analysis. Analysis revealed that cortical and striatal Aβ plaque burdens were similar in DSD + and DSD - cases. In both groups, most FC plaques were neuritic, while striatal plaques were diffuse. By contrast, FC AT8-positive NFTs and neuropil thread densities were significantly greater in DSD + compared to DSD -, while striatal NFT densities were similar between groups. FC pS422-positive and TauC3 NFT densities were significantly greater than Alz50-labeled NFTs in DSD + , but not DSD - cases. Putaminal, but not caudate pS422-positive NFT density, was significantly greater than TauC3-positive NFTs. In the FC, AT8 + pS422 + Alz50, TauC3 + pS422 + Alz50, pS422 + Alz50, and TauC3 + pS422 positive NFTs were more frequent in DSD + compared to DSD- cases. Single gene-array profiling of FC pS422 positive neurons revealed downregulation of 63 of a total of 864 transcripts related to Aβ/tau biology, glutamatergic, cholinergic, and monoaminergic metabolism, intracellular signaling, cell homeostasis, and cell death in DSD + compared DSD - cases. These observations suggest that abnormal tau aggregation plays a critical role in the development of dementia in DS.
Collapse
Affiliation(s)
- Sylvia E Perez
- Department of Neurobiology and Neurology, Barrow Neurological Institute, 350 W. Thomas St, Phoenix, AZ, 85013, USA
- School of Life Sciences, College of Liberal Arts and Sciences, Arizona State University, Tempe, AZ, 85287, USA
| | - Jennifer C Miguel
- Department of Neurobiology and Neurology, Barrow Neurological Institute, 350 W. Thomas St, Phoenix, AZ, 85013, USA
| | - Bin He
- Department of Neurobiology and Neurology, Barrow Neurological Institute, 350 W. Thomas St, Phoenix, AZ, 85013, USA
| | | | - Eric E Abrahamson
- Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, Pittsburgh, PA, 15213, USA
- Departments of Neurology and Psychiatry, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Milos D Ikonomovic
- Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, Pittsburgh, PA, 15213, USA
- Departments of Neurology and Psychiatry, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Ira Lott
- Departments of Pediatrics and Neurology, University of California, Irvine, CA, 92697, USA
| | - Eric Doran
- Departments of Pediatrics and Neurology, University of California, Irvine, CA, 92697, USA
| | - Melissa J Alldred
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, 10962, USA
- Departments of Psychiatry, NYU Neuroscience Institute, NYU Langone Medical Center, New York, NY, 10021, USA
| | - Stephen D Ginsberg
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, 10962, USA
- Departments of Psychiatry, NYU Neuroscience Institute, NYU Langone Medical Center, New York, NY, 10021, USA
- Departments of Neuroscience and Physiology, The NYU Neuroscience Institute, NYU Langone Medical Center, New York, NY, 10021, USA
| | - Elliott J Mufson
- Department of Neurobiology and Neurology, Barrow Neurological Institute, 350 W. Thomas St, Phoenix, AZ, 85013, USA.
| |
Collapse
|
16
|
Rojas AV, Maisuradze GG, Scheraga HA. Dependence of the Formation of Tau and Aβ Peptide Mixed Aggregates on the Secondary Structure of the N-Terminal Region of Aβ. J Phys Chem B 2018; 122:7049-7056. [PMID: 29940109 DOI: 10.1021/acs.jpcb.8b04647] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
One of the hallmarks of Alzheimer's disease is the formation of aggregates of the tau protein, a process that can be facilitated by the presence of fibrils formed by the amyloid β peptide (Aβ). However, the mechanism that triggers tau aggregation is still a matter of debate. The effect of Aβ40 fibrils on the aggregation of the repeat domain of tau (TauRD) is investigated here by employing coarse-grained molecular dynamics simulations. The results indicate that the repeat domain of tau has a high affinity for Aβ40 fibrils, with the 261GSTENLK267 fragment of tau driving TauRD toward the 16KLVFFA21 fragment in Aβ40. Monomeric Aβ40, in which the 16KLVFFA21 fragment is rarely found in an extended conformation (as in the fibril), has a low affinity for the TauRD, indicating that the ability of Aβ40 fibrils to bind to the TauRD depends on the 16KLVFFA21 fragment of Aβ adopting an extended conformation.
Collapse
Affiliation(s)
- Ana V Rojas
- Schrödinger, Inc. , 120 West 45th Street , New York , New York 10036 , United States
| | - Gia G Maisuradze
- Baker Laboratory of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - Harold A Scheraga
- Baker Laboratory of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| |
Collapse
|
17
|
Park S, Lee JH, Jeon JH, Lee MJ. Degradation or aggregation: the ramifications of post-translational modifications on tau. BMB Rep 2018; 51:265-273. [PMID: 29661268 PMCID: PMC6033068 DOI: 10.5483/bmbrep.2018.51.6.077] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Indexed: 01/06/2023] Open
Abstract
Tau protein is encoded in the microtubule-associated protein tau (MAPT) gene and contributes to the stability of microtubules in axons. Despite of its basic isoelectric point and high solubility, tau is often found in intraneuronal filamentous inclusions such as paired helical filaments (PHFs), which are the primary constituent of neurofibrillary tangles (NFTs). This pathological feature is the nosological entity termed "tauopathies" which notably include Alzheimer's disease (AD). A proteinaceous signature of all tauopathies is hyperphosphorylation of the accumulated tau, which has been extensively studied as a major pharmacological target for AD therapy. However, in addition to phosphorylation events, tau undergoes a number of diverse posttranslational modifications (PTMs) which appear to be controlled by complex crosstalk. It remains to be elucidated which of the PTMs or their combinations have pro-aggregation or anti-aggregation properties. In this review, we outline the consequences of and communications between several key PTMs of tau, such as acetylation, phosphorylation, and ubiquitination, focusing on their roles in aggregation and degradation. We place emphasis on the structure of tau protofilaments from the human AD brain, which may be good targets to modulate etiological PTMs which cause tau aggregation. [BMB Reports 2018; 51(6): 265-273].
Collapse
Affiliation(s)
- Seoyoung Park
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul 03080,
Korea
- Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080,
Korea
| | - Jung Hoon Lee
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul 03080,
Korea
- Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080,
Korea
| | - Jun Hyoung Jeon
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul 03080,
Korea
| | - Min Jae Lee
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul 03080,
Korea
- Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080,
Korea
- Department of Biomedical Sciences, Seoul National University Graduate School, Seoul 03080,
Korea
| |
Collapse
|
18
|
Stepanov A, Karelina T, Markevich N, Demin O, Nicholas T. A mathematical model of multisite phosphorylation of tau protein. PLoS One 2018; 13:e0192519. [PMID: 29408874 PMCID: PMC5800643 DOI: 10.1371/journal.pone.0192519] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/24/2018] [Indexed: 11/18/2022] Open
Abstract
Abnormal tau metabolism followed by formation of tau deposits causes a number of neurodegenerative diseases called tauopathies including Alzheimer's disease. Hyperphosphorylation of tau protein precedes tau aggregation and is a topic of interest for the development of pharmacological interventions to prevent pathology progression at early stages. The development of a mathematical model of multisite phosphorylation of tau would be helpful for searching for the targets of pharmacological interventions and candidates for biomarkers of pathology progression. In the present study, we for the first time developed a model of multisite phosphorylation of tau protein and elucidated the relative contribution of kinases to phosphorylation of distinct sites. The model describes phosphorylation of tau or PKA-prephosphorylated tau by GSK3β and CDK5 and dephosphorylation by PP2A, accurately reproducing the data for short-term kinetics of tau (de)phosphorylation. Our results suggest that kinase inhibition may more specifically prevent tau hyperphosphorylation, e.g., on PHF sites, which are key biomarkers of pathological changes in Alzheimer's disease. The main features of our model are partial phosphorylation of tau residues and merging of random and sequential mechanisms of multisite phosphorylation within the framework of the probability-based approach assuming independent phosphorylation events.
Collapse
Affiliation(s)
| | | | | | | | - Timothy Nicholas
- Pfizer Global R&D, Groton, Connecticut, United States of America
| |
Collapse
|
19
|
Tau-based therapies in neurodegeneration: opportunities and challenges. Nat Rev Drug Discov 2017; 16:863-883. [DOI: 10.1038/nrd.2017.155] [Citation(s) in RCA: 155] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
20
|
Niewidok B, Igaev M, Sündermann F, Janning D, Bakota L, Brandt R. Presence of a carboxy-terminal pseudorepeat and disease-like pseudohyperphosphorylation critically influence tau's interaction with microtubules in axon-like processes. Mol Biol Cell 2016; 27:3537-3549. [PMID: 27582388 PMCID: PMC5221586 DOI: 10.1091/mbc.e16-06-0402] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/24/2016] [Indexed: 12/31/2022] Open
Abstract
A refined FDAP approach is used to analyze tau’s behavior in axon-like processes. A conserved C-terminal pseudorepeat and disease-like pseudohyperphosphorylation critically influence tau’s microtubule interaction. The results contribute to an understanding of pathological processes that lead to tau’s redistribution during disease. A current challenge of cell biology is to investigate molecular interactions in subcellular compartments of living cells to overcome the artificial character of in vitro studies. To dissect the interaction of the neuronal microtubule (MT)-associated protein tau with MTs in axon-like processes, we used a refined fluorescence decay after photoactivation approach and single-molecule tracking. We found that isoform variation had only a minor influence on the tau–MT interaction, whereas the presence of a C-terminal pseudorepeat region (PRR) greatly increased MT binding by a greater-than-sixfold reduction of the dissociation rate. Bioinformatic analysis revealed that the PRR contained a highly conserved motif of 18 amino acids. Disease-associated tau mutations in the PRR (K369I, G389R) did not influence apparent MT binding but increased its dynamicity. Simulation of disease-like tau hyperphosphorylation dramatically diminished the tau–MT interaction by a greater-than-fivefold decrease of the association rate with no major change in the dissociation rate. Apparent binding of tau to MTs was similar in axons and dendrites but more sensitive to increased phosphorylation in axons. Our data indicate that under the conditions of high MT density that prevail in the axon, tau’s MT binding and localization are crucially affected by the presence of the PRR and tau hyperphosphorylation.
Collapse
Affiliation(s)
- Benedikt Niewidok
- Department of Neurobiology, University of Osnabrück, 49076 Osnabrück, Germany
| | - Maxim Igaev
- Department of Neurobiology, University of Osnabrück, 49076 Osnabrück, Germany
| | - Frederik Sündermann
- Department of Neurobiology, University of Osnabrück, 49076 Osnabrück, Germany
| | - Dennis Janning
- Department of Neurobiology, University of Osnabrück, 49076 Osnabrück, Germany
| | - Lidia Bakota
- Department of Neurobiology, University of Osnabrück, 49076 Osnabrück, Germany
| | - Roland Brandt
- Department of Neurobiology, University of Osnabrück, 49076 Osnabrück, Germany
| |
Collapse
|
21
|
Tau-Centric Targets and Drugs in Clinical Development for the Treatment of Alzheimer's Disease. BIOMED RESEARCH INTERNATIONAL 2016; 2016:3245935. [PMID: 27429978 PMCID: PMC4939203 DOI: 10.1155/2016/3245935] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 05/19/2016] [Indexed: 11/17/2022]
Abstract
The failure of several Phase II/III clinical trials in Alzheimer's disease (AD) with drugs targeting β-amyloid accumulation in the brain fuelled an increasing interest in alternative treatments against tau pathology, including approaches targeting tau phosphatases/kinases, active and passive immunization, and anti-tau aggregation. The most advanced tau aggregation inhibitor (TAI) is methylthioninium (MT), a drug existing in equilibrium between a reduced (leuco-methylthioninium) and oxidized form (MT+). MT chloride (methylene blue) was investigated in a 24-week Phase II clinical trial in 321 patients with mild to moderate AD that failed to show significant positive effects in mild AD patients, although long-term observations (50 weeks) and biomarker studies suggested possible benefit. The dose of 138 mg/day showed potential benefits on cognitive performance of moderately affected AD patients and cerebral blood flow in mildly affected patients. Further clinical evidence will come from the large ongoing Phase III trials for the treatment of AD and the behavioral variant of frontotemporal dementia on a new form of this TAI, more bioavailable and less toxic at higher doses, called TRx0237. More recently, inhibitors of tau acetylation are being actively pursued based on impressive results in animal studies obtained by salsalate, a clinically used derivative of salicylic acid.
Collapse
|
22
|
Kanaan NM, Cox K, Alvarez VE, Stein TD, Poncil S, McKee AC. Characterization of Early Pathological Tau Conformations and Phosphorylation in Chronic Traumatic Encephalopathy. J Neuropathol Exp Neurol 2016; 75:19-34. [PMID: 26671985 DOI: 10.1093/jnen/nlv001] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Chronic traumatic encephalopathy (CTE) is a neurodegenerative tauopathy that develops after repetitive head injury. Several lines of evidence in other tauopathies suggest that tau oligomer formation induces neurotoxicity and that tau oligomer-mediated neurotoxicity involves induction of axonal dysfunction through exposure of an N-terminal motif in tau, the phosphatase-activating domain (PAD). Additionally, phosphorylation at serine 422 in tau occurs early and correlates with cognitive decline in patients with Alzheimer disease (AD). We performed immunohistochemistry and immunofluorescence on fixed brain sections and biochemical analysis of fresh brain extracts to characterize the presence of PAD-exposed tau (TNT1 antibody), tau oligomers (TOC1 antibody), tau phosphorylated at S422 (pS422 antibody), and tau truncated at D421 (TauC3 antibody) in the brains of 9-11 cases with CTE and cases of nondemented aged controls and AD (Braak VI) (n = 6, each). All 3 early tau markers (ie, TNT1, TOC1, and pS422) were present in CTE and displayed extensive colocalization in perivascular tau lesions that are considered diagnostic for CTE. Notably, the TauC3 epitope, which is abundant in AD, was relatively sparse in CTE. Together, these results provide the first description of PAD exposure, TOC1 reactive oligomers, phosphorylation of S422, and TauC3 truncation in the tau pathology of CTE.
Collapse
|
23
|
Medina M, Hernández F, Avila J. New Features about Tau Function and Dysfunction. Biomolecules 2016; 6:biom6020021. [PMID: 27104579 PMCID: PMC4919916 DOI: 10.3390/biom6020021] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 03/09/2016] [Accepted: 04/13/2016] [Indexed: 12/24/2022] Open
Abstract
Tau is a brain microtubule-associated protein that directly binds to a microtubule and dynamically regulates its structure and function. Under pathological conditions, tau self-assembles into filamentous structures that end up forming neurofibrillary tangles. Prominent tau neurofibrillary pathology is a common feature in a number of neurodegenerative disorders, collectively referred to as tauopathies, the most common of which is Alzheimer’s disease (AD). Beyond its classical role as a microtubule-associated protein, recent advances in our understanding of tau cellular functions have revealed novel insights into their important role during pathogenesis and provided potential novel therapeutic targets. Regulation of tau behavior and function under physiological and pathological conditions is mainly achieved through post-translational modifications, including phosphorylation, glycosylation, acetylation, and truncation, among others, indicating the complexity and variability of factors influencing regulation of tau toxicity, all of which have significant implications for the development of novel therapeutic approaches in various neurodegenerative disorders. A more comprehensive understanding of the molecular mechanisms regulating tau function and dysfunction will provide us with a better outline of tau cellular networking and, hopefully, offer new clues for designing more efficient approaches to tackle tauopathies in the near future.
Collapse
Affiliation(s)
- Miguel Medina
- CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Valderrebollo 5, 28031 Madrid, Spain.
- CIEN Foundation, Valderrebollo 5, 28041 Madrid, Spain.
| | - Félix Hernández
- CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Valderrebollo 5, 28031 Madrid, Spain.
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás cabrera 1, 28049 Madrid, Spain.
| | - Jesús Avila
- CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Valderrebollo 5, 28031 Madrid, Spain.
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás cabrera 1, 28049 Madrid, Spain.
| |
Collapse
|
24
|
Heinisch JJ, Brandt R. Signaling pathways and posttranslational modifications of tau in Alzheimer's disease: the humanization of yeast cells. MICROBIAL CELL 2016; 3:135-146. [PMID: 28357346 DOI: 10.15698/mic2016.04.489] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In the past decade, yeast have been frequently employed to study the molecular mechanisms of human neurodegenerative diseases, generally by means of heterologous expression of genes encoding the relevant hallmark proteins. However, it has become evident that substantial posttranslational modifications of many of these proteins are required for the development and progression of potentially disease relevant changes. This is exemplified by the neuronal tau proteins, which are critically involved in a class of neuro-degenerative diseases collectively called tauopathies and which includes Alz-heimer's disease (AD) as its most common representative. In the course of the disease, tau changes its phosphorylation state and becomes hyperphosphory-lated, gets truncated by proteolytic cleavage, is subject to O-glycosylation, sumoylation, ubiquitinylation, acetylation and some other modifications. This poses the important question, which of these posttranslational modifications are naturally occurring in the yeast model or can be reconstituted by heterol-ogous gene expression. Here, we present an overview on common modifica-tions as they occur in tau during AD, summarize their potential relevance with respect to disease mechanisms and refer to the native yeast enzyme orthologs capable to perform these modifications. We will also discuss potential approaches to humanize yeast in order to create modification patterns resembling the situation in mammalian cells, which could enhance the value of Saccharomyces cerevisiae and Kluyveromyces lactis as disease models.
Collapse
Affiliation(s)
- Jürgen J Heinisch
- Universität Osnabrück, Fachbereich Biologie/Chemie, AG Genetik, Barbarastr. 11, D-49076 Osnabrück, Germany
| | - Roland Brandt
- Universität Osnabrück, Fachbereich Biologie/Chemie, AG Neurobiologie, Barbarastr. 11, D-49076 Osnabrück, Germany
| |
Collapse
|
25
|
Heinisch JJ, Brandt R. Signaling pathways and posttranslational modifications of tau in Alzheimer's disease: the humanization of yeast cells. MICROBIAL CELL 2016. [PMID: 28357346 DOI: 10.15698/mic2016.04] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In the past decade, yeast have been frequently employed to study the molecular mechanisms of human neurodegenerative diseases, generally by means of heterologous expression of genes encoding the relevant hallmark proteins. However, it has become evident that substantial posttranslational modifications of many of these proteins are required for the development and progression of potentially disease relevant changes. This is exemplified by the neuronal tau proteins, which are critically involved in a class of neuro-degenerative diseases collectively called tauopathies and which includes Alz-heimer's disease (AD) as its most common representative. In the course of the disease, tau changes its phosphorylation state and becomes hyperphosphory-lated, gets truncated by proteolytic cleavage, is subject to O-glycosylation, sumoylation, ubiquitinylation, acetylation and some other modifications. This poses the important question, which of these posttranslational modifications are naturally occurring in the yeast model or can be reconstituted by heterol-ogous gene expression. Here, we present an overview on common modifica-tions as they occur in tau during AD, summarize their potential relevance with respect to disease mechanisms and refer to the native yeast enzyme orthologs capable to perform these modifications. We will also discuss potential approaches to humanize yeast in order to create modification patterns resembling the situation in mammalian cells, which could enhance the value of Saccharomyces cerevisiae and Kluyveromyces lactis as disease models.
Collapse
Affiliation(s)
- Jürgen J Heinisch
- Universität Osnabrück, Fachbereich Biologie/Chemie, AG Genetik, Barbarastr. 11, D-49076 Osnabrück, Germany
| | - Roland Brandt
- Universität Osnabrück, Fachbereich Biologie/Chemie, AG Neurobiologie, Barbarastr. 11, D-49076 Osnabrück, Germany
| |
Collapse
|
26
|
Abnormal tau induces cognitive impairment through two different mechanisms: synaptic dysfunction and neuronal loss. Sci Rep 2016; 6:20833. [PMID: 26888634 PMCID: PMC4757872 DOI: 10.1038/srep20833] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 01/08/2016] [Indexed: 01/26/2023] Open
Abstract
The hyperphosphorylated microtubule-associated protein tau is present in several neurodegenerative diseases, although the causal relationship remains elusive. Few mouse models used to study Alzheimer-like dementia target tau phosphorylation. We created an inducible pseudophosphorylated tau (Pathological Human Tau, PH-Tau) mouse model to study the effect of conformationally modified tau in vivo. Leaky expression resulted in two levels of PH-Tau: low basal level and higher upon induction (4% and 14% of the endogenous tau, respectively). Unexpectedly, low PH-Tau resulted in significant cognitive deficits, decrease in the number of synapses (seen by EM in the CA1 region), reduction of synaptic proteins, and localization to the nucleus. Induction of PH-Tau triggered neuronal death (60% in CA3), astrocytosis, and loss of the processes in CA1. These findings suggest, that phosphorylated tau is sufficient to induce neurodegeneration and that two different mechanisms can induce cognitive impairment depending on the levels of PH-Tau expression.
Collapse
|
27
|
Bukar Maina M, Al-Hilaly YK, Serpell LC. Nuclear Tau and Its Potential Role in Alzheimer's Disease. Biomolecules 2016; 6:9. [PMID: 26751496 PMCID: PMC4808803 DOI: 10.3390/biom6010009] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/16/2015] [Accepted: 12/23/2015] [Indexed: 12/14/2022] Open
Abstract
Tau protein, found in both neuronal and non-neuronal cells, forms aggregates in neurons that constitutes one of the hallmarks of Alzheimer’s disease (AD). For nearly four decades, research efforts have focused more on tau’s role in physiology and pathology in the context of the microtubules, even though, for over three decades, tau has been localised in the nucleus and the nucleolus. Its nuclear and nucleolar localisation had stimulated many questions regarding its role in these compartments. Data from cell culture, mouse brain, and the human brain suggests that nuclear tau could be essential for genome defense against cellular distress. However, its nature of translocation to the nucleus, its nuclear conformation and interaction with the DNA and other nuclear proteins highly suggest it could play multiple roles in the nucleus. To find efficient tau-based therapies, there is a need to understand more about the functional relevance of the varied cellular distribution of tau, identify whether specific tau transcripts or isoforms could predict tau’s localisation and function and how they are altered in diseases like AD. Here, we explore the cellular distribution of tau, its nuclear localisation and function and its possible involvement in neurodegeneration.
Collapse
Affiliation(s)
- Mahmoud Bukar Maina
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, East Sussex, UK.
- Department of Human Anatomy, College of Medical Science, Gombe State University, Gombe 760, Nigeria.
| | - Youssra K Al-Hilaly
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, East Sussex, UK.
- Chemistry Department, College of Sciences, Al-Mustansiriyah University, Baghdad, Iraq.
| | - Louise C Serpell
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, East Sussex, UK.
| |
Collapse
|
28
|
Liu G, Liu C, Zhang XN. Comparison of the neuropsychological mechanisms of 2,6-diisopropylphenol and N-methyl-D-aspartate receptor antagonist against electroconvulsive therapy-induced learning and memory impairment in depressed rats. Mol Med Rep 2015; 12:3297-3308. [PMID: 25998151 PMCID: PMC4526078 DOI: 10.3892/mmr.2015.3803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 04/14/2015] [Indexed: 11/06/2022] Open
Abstract
The present study aimed to examine the neurophysiological mechanisms of the 2,6-diisopropylphenol and N-methyl-D-aspartate (NMDA) receptor antagonist against learning and memory impairment, induced by electroconvulsive therapy (ECT). A total of 48 adult depressed rats without olfactory bulbs were randomly divided into six experimental groups: i) saline; ii) 10 mg/kg MK‑801; iii) 10 mg/kg MK‑801 and a course of ECT; iv) 200 mg/kg 2,6‑diisopropylphenol; v) 200 mg/kg 2,6‑diisopropylphenol and a course of ECT; and vi) saline and a course of ECT. The learning and memory abilities of the rats were assessed using a Morris water maze 1 day after a course of ECT. The hippocampus was removed 1 day after assessment using the Morris water maze assessment. The content of glutamate in the hippocampus was detected using high‑performance liquid chromatography. The expression levels of p‑AT8Ser202 and GSK‑3β1H8 in the hippocampus were determined using immunohistochemical staining and western blot analysis. The results demonstrated that the 2,6‑diisopropylphenol NMDA receptor antagonist, MK‑801 and ECT induced learning and memory impairment in the depressed rats. The glutamate content was significantly upregulated by ECT, reduced by 2,6‑diisopropylphenol, and was unaffected by the NMDA receptor antagonist in the hippocampus of the depressed rats. Tau protein hyperphosphorylation in the hippocampus was upregulated by ECT, but was reduced by 2,6‑diisopropylphenol and the MK‑801 NMDA receptor antagonist. It was also demonstrated that 2,6‑diisopropylphenol prevented learning and memory impairment and reduced the hyperphosphorylation of the Tau protein, which was induced by eECT. GSK‑3β was found to be the key protein involved in this signaling pathway. The ECT reduced the learning and memory impairment, caused by hyperphosphorylation of the Tau protein, in the depressed rats by upregulating the glutamate content.
Collapse
Affiliation(s)
- Gang Liu
- Department of Anesthesiology, General Hospital of Beijing Military Area of PLA, Beijing 100700, P.R. China
| | - Chao Liu
- Department of Anesthesiology, Tianjin Chest Hospital, Tianjin 300222, P.R. China
| | - Xue-Ning Zhang
- Department of Radiology, The Second Hospital of Tianjin Medical University, Tianjin 300211, P.R. China
| |
Collapse
|