1
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Donison N, Hintermayer M, Subramaniam M, Santandrea E, Volkening K, Strong MJ. Upregulation of LRRK2 following traumatic brain injury does not directly phosphorylate Thr 175 tau. Front Cell Neurosci 2023; 17:1272899. [PMID: 38026695 PMCID: PMC10663351 DOI: 10.3389/fncel.2023.1272899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 10/23/2023] [Indexed: 12/01/2023] Open
Abstract
Phosphorylated microtubule-associated protein tau (tau) aggregates are a pathological hallmark of various neurodegenerative diseases, including chronic traumatic encephalopathy and amyotrophic lateral sclerosis with cognitive impairment. While there are many residues phosphorylated on tau, phosphorylation of threonine 175 (pThr175 tau) has been shown to initiate fibril formation in vitro and is present in pathological tau aggregates in vivo. Given this, preventing Thr175 tau phosphorylation presents a potential approach to reduce fibril formation; however, the kinase(s) acting on Thr175 are not yet fully defined. Using a single controlled cortical impact rodent model of traumatic brain injury (TBI), which rapidly induces Thr175 tau phosphorylation, we observed an upregulation and alteration in subcellular localization of leucine-rich repeat kinase 2 (LRRK2), a kinase that has been implicated in tau phosphorylation. LRRK2 upregulation was evident by one-day post-injury and persisted to day 10. The most notable changes were observed in microglia at the site of injury in the cortex. To determine if the appearance of pThr175 tau was causally related to the upregulation of LRRK2 expression, we examined the ability of LRRK2 to phosphorylate Thr175in vitro by co-transfecting 2N4R human WT-tau with either LRRK2-WT, constitutively-active LRRK2-G2019S or inactive LRRK2-3XKD. We found no significant difference in the level of pThr175 tau between the overexpression of LRRK2-WT, -G2019S or -3XKD, suggesting LRRK2 does not phosphorylate tau at Thr175. Further, downstream events known to follow Thr175 phosphorylation and known to be associated with pathological tau fibril formation (pSer9-GSK3β and pThr231 tau induction) also remained unchanged. We conclude that while LRRK2 expression is altered in TBI, it does not contribute directly to pThr175 tau generation.
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Affiliation(s)
- Neil Donison
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Matthew Hintermayer
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Maegha Subramaniam
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Erin Santandrea
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Kathryn Volkening
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Michael J. Strong
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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2
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Vacchiano V, Mastrangelo A, Zenesini C, Baiardi S, Avoni P, Polischi B, Capellari S, Salvi F, Liguori R, Parchi P. Elevated plasma p-tau181 levels unrelated to Alzheimer's disease pathology in amyotrophic lateral sclerosis. J Neurol Neurosurg Psychiatry 2023; 94:428-435. [PMID: 37012065 DOI: 10.1136/jnnp-2022-330709] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 03/15/2023] [Indexed: 04/05/2023]
Abstract
BACKGROUND Phosphorylated-tau181 (p-tau181), a specific marker of Alzheimer's disease (AD) pathology, was found elevated in plasma but not in cerebrospinal fluid (CSF) of patients with amyotrophic lateral sclerosis (ALS). We expanded these findings in a larger patient cohort, exploring clinical/electrophysiological associations, prognostic value and longitudinal trajectories of the biomarker. METHODS We obtained baseline plasma samples from 148 ALS, 12 spinal muscular atrophy (SMA), and 88 AD patients, and 60 healthy controls. Baseline CSF and longitudinal plasma samples were from 130 and 39 patients with ALS. CSF AD markers were measured with the Lumipulse platform, and plasma p-tau181 with SiMoA. RESULTS Patients with ALS showed higher plasma p-tau181 levels than controls (p<0.001) and lower than AD participants (p=0.02). SMA patients had higher levels than controls (p=0.03). In patients with ALS, CSF p-tau and plasma p-tau181 did not correlate (p=0.37). Plasma p-tau181 significantly increased with the number of regions showing clinical/neurophysiological lower motor neurons (LMN) signs (p=0.007) and correlated with the degree of denervation in the lumbosacral area (r=0.51, p<0.0001). Plasma p-tau181 levels were higher in classic and LMN-predominant than in bulbar phenotype (p=0.004 and p=0.006). Multivariate Cox regression confirmed plasma p-tau181 as an independent prognostic factor in ALS (HR 1.90, 95% CI 1.25 to 2.90, p=0.003). Longitudinal analysis showed a significant rise in plasma p-tau181 values over time, especially in fast progressors. CONCLUSIONS Plasma p-tau181 is elevated in patients with ALS, independently from CSF levels, and is firmly associated with LMN dysfunction. The finding indicates that p-tau181 of putative peripheral origin might represent a confounding factor in using plasma p-tau181 for AD pathology screening, which deserves further investigation.
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Affiliation(s)
- Veria Vacchiano
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Andrea Mastrangelo
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
| | - Corrado Zenesini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Simone Baiardi
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Patrizia Avoni
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Barbara Polischi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Sabina Capellari
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Fabrizio Salvi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Rocco Liguori
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Piero Parchi
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
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3
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Yagita K, Sasagasako N, Koyama S, Noguchi H, Honda H. Amyotrophic lateral sclerosis with TDP-43 abnormalities exhibiting globular glial tau inclusions in frontotemporal lobes and pallido-nigral system. Neuropathology 2023; 43:117-126. [PMID: 36003035 DOI: 10.1111/neup.12862] [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: 05/30/2022] [Revised: 07/28/2022] [Accepted: 08/03/2022] [Indexed: 02/04/2023]
Abstract
Here we present the autopsy case of an 80-year-old woman with a 9-year history of motor neuron disease and atypical Parkinsonism. Her initial symptom was gait disturbance, and she subsequently developed limb weakness and Parkinsonism without response to levodopa. Her motor symptoms progressed to bulbar palsy, and she died of respiratory failure. Postmortem examination revealed characteristic findings of amyotrophic lateral sclerosis (ALS), including motor neuronal loss with astrogliosis, corticospinal tract degeneration, and TAR DNA-binding protein of 43 kDa abnormalities, including nuclear loss and skein-like inclusions. In contrast, severe tau pathological changes were seen in the frontotemporal lobes and pallido-nigral system. Tau pathologies affected not only neuronal components, such as neurofibrillary tangles and neuropil threads, but also glial cells (astrocytes and oligodendrocytes). Some glial tau pathologies exhibited peculiar round accumulations, reminiscent of globular glial inclusions (GGIs) in globular glial tauopathy. This unique autopsy case demonstrates that ALS with TDP-43 could be comorbid with globular glial tau inclusions and indicates that common pathological mechanisms exist among ALS and GGI formation.
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Affiliation(s)
- Kaoru Yagita
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Naokazu Sasagasako
- Department of Neurology, Neuro-Muscular Center, National Omuta Hospital, Omuta, Japan
| | - Sachiko Koyama
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hideko Noguchi
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroyuki Honda
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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4
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Cousins KAQ, Shaw LM, Shellikeri S, Dratch L, Rosario L, Elman LB, Quinn C, Amado DA, Wolk DA, Tropea TF, Chen-Plotkin A, Irwin DJ, Grossman M, Lee EB, Trojanowski JQ, McMillan CT. Elevated Plasma Phosphorylated Tau 181 in Amyotrophic Lateral Sclerosis. Ann Neurol 2022; 92:807-818. [PMID: 35877814 PMCID: PMC9588516 DOI: 10.1002/ana.26462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 07/21/2022] [Accepted: 07/23/2022] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Plasma phosphorylated tau (p-tau181 ) is reliably elevated in Alzheimer's disease (AD), but less explored is its specificity relative to other neurodegenerative conditions. Here, we find novel evidence that plasma p-tau181 is elevated in amyotrophic lateral sclerosis (ALS), a neurodegenerative condition typically lacking tau pathology. We performed a detailed evaluation to identify the clinical correlates of elevated p-tau181 in ALS. METHODS Patients were clinically or pathologically diagnosed with ALS (n = 130) or AD (n = 79), or were healthy non-impaired controls (n = 26). Receiver operating characteristic (ROC) curves were analyzed and area under the curve (AUC) was used to discriminate AD from ALS. Within ALS, Mann-Whitney-Wilcoxon tests compared analytes by presence/absence of upper motor neuron and lower motor neuron (LMN) signs. Spearman correlations tested associations between plasma p-tau181 and postmortem neuron loss. RESULTS A Wilcoxon test showed plasma p-tau181 was higher in ALS than controls (W = 2,600, p = 0.000015), and ROC analyses showed plasma p-tau181 poorly discriminated AD and ALS (AUC = 0.60). In ALS, elevated plasma p-tau181 was associated with LMN signs in cervical (W = 827, p = 0.0072), thoracic (W = 469, p = 0.00025), and lumbosacral regions (W = 851, p = 0.0000029). In support of LMN findings, plasma p-tau181 was associated with neuron loss in the spinal cord (rho = 0.46, p = 0.017), but not in the motor cortex (p = 0.41). Cerebrospinal spinal fluid p-tau181 and plasma neurofilament light chain were included as reference analytes, and demonstrate specificity of findings. INTERPRETATION We found strong evidence that plasma p-tau181 is elevated in ALS and may be a novel marker specific to LMN dysfunction. ANN NEUROL 2022;92:807-818.
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Affiliation(s)
- Katheryn A Q Cousins
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Leslie M Shaw
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA
| | - Sanjana Shellikeri
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Laynie Dratch
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Luis Rosario
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Lauren B Elman
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Colin Quinn
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Defne A Amado
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - David A Wolk
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Thomas F Tropea
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Alice Chen-Plotkin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Murray Grossman
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Edward B Lee
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA
| | - Corey T McMillan
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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5
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Strong MJ, Donison NS, Volkening K. Alterations in Tau Metabolism in ALS and ALS-FTSD. Front Neurol 2020; 11:598907. [PMID: 33329356 PMCID: PMC7719764 DOI: 10.3389/fneur.2020.598907] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/27/2020] [Indexed: 12/15/2022] Open
Abstract
There is increasing acceptance that amyotrophic lateral sclerosis (ALS), classically considered a neurodegenerative disease affecting almost exclusively motor neurons, is syndromic with both clinical and biological heterogeneity. This is most evident in its association with a broad range of neuropsychological, behavioral, speech and language deficits [collectively termed ALS frontotemporal spectrum disorder (ALS-FTSD)]. Although the most consistent pathology of ALS and ALS-FTSD is a disturbance in TAR DNA binding protein 43 kDa (TDP-43) metabolism, alterations in microtubule-associated tau protein (tau) metabolism can also be observed in ALS-FTSD, most prominently as pathological phosphorylation at Thr175 (pThr175tau). pThr175 has been shown to promote exposure of the phosphatase activating domain (PAD) in the tau N-terminus with the consequent activation of GSK3β mediated phosphorylation at Thr231 (pThr231tau) leading to pathological oligomer formation. This pathological cascade of tau phosphorylation has been observed in chronic traumatic encephalopathy with ALS (CTE-ALS) and in both in vivo and in vitro experimental paradigms, suggesting that it is of critical relevance to the pathobiology of ALS-FTSD. It is also evident that the co-existence of alterations in the metabolism of TDP-43 and tau acts synergistically in a rodent model to exacerbate the pathology of either.
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Affiliation(s)
- Michael J Strong
- Molecular Medicine, Schulich School of Medicine and Dentistry, Robarts Research Institute, Western University, London, ON, Canada.,Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Neil S Donison
- Molecular Medicine, Schulich School of Medicine and Dentistry, Robarts Research Institute, Western University, London, ON, Canada.,Neuroscience Graduate Program, Western University, London, ON, Canada
| | - Kathryn Volkening
- Molecular Medicine, Schulich School of Medicine and Dentistry, Robarts Research Institute, Western University, London, ON, Canada.,Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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6
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Shellikeri S, Keith J, Black SE, Zinman L, Yunusova Y. Neuropathology of Speech Network Distinguishes Bulbar From Nonbulbar Amyotrophic Lateral Sclerosis. J Neuropathol Exp Neurol 2020; 79:284-295. [PMID: 31951003 DOI: 10.1093/jnen/nlz130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 11/26/2019] [Indexed: 12/14/2022] Open
Abstract
Bulbar amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative subtype affecting speech and swallowing motor functions as well as associated with the burden of cognitive deficits. The neuroanatomical underpinnings of bulbar ALS are not well understood. The aim of this study was to compare neuropathology of the speech network (SpN) between 3 cases of bulbar-onset ALS (bALS), 3 cases of spinal-onset ALS (sALS) with antemortem bulbar ALS (sALSwB) against 3 sALS without antemortem bulbar ALS (sALSnoB) and 3 controls. Regional distribution and severity of neuronal loss, TDP-43 (transactive response DNA-binding protein of 43 kDa), and tau proteinopathy were examined. All 3 bALS cases showed marked neuronal loss and severe proteinopathy across most SpN regions; sALSwB cases showed no neuronal loss but mild and variable TDP-43 pathology in focal regions; sALSnoB cases demonstrated an absence of pathology. Two bALS cases had coexisting tauopathy in SpN regions, which was not noted in any sALS cases. The findings suggested that bALS may have a distinct neuropathological signature characterized by marked neuronal loss and polypathology in the SpN. Milder TDP-43 pathology in the SpN for sALSwB cases suggested a link between severity of bulbar ALS and SpN damage. Findings support a clinicopathologic link between bulbar symptoms and pathology in the SpN.
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Affiliation(s)
- Sanjana Shellikeri
- Department of Speech-Language Pathology & Rehabilitation Sciences Institute, University of Toronto.,Hurvitz Brain Sciences Program, Sunnybrook Research Institute
| | - Julia Keith
- Laboratory Medicine and Molecular Diagnostics, Anatomic Pathology, Sunnybrook Health Sciences Centre, and Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto
| | - Sandra E Black
- Hurvitz Brain Sciences Program, Sunnybrook Research Institute.,Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre.,L.C. Campbell Cognitive Neurology Research Unit, Cognitive Neurology, Sunnybrook Research Institute, University of Toronto.,Rotman Research Institute, Baycrest
| | - Lorne Zinman
- Hurvitz Brain Sciences Program, Sunnybrook Research Institute.,Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre.,L.C. Campbell Cognitive Neurology Research Unit, Cognitive Neurology, Sunnybrook Research Institute, University of Toronto
| | - Yana Yunusova
- Department of Speech-Language Pathology & Rehabilitation Sciences Institute, University of Toronto.,Hurvitz Brain Sciences Program, Sunnybrook Research Institute.,University Health Network - Toronto Rehabilitation Institute (YY), Toronto, Ontario, Canada
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7
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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.
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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
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8
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Moszczynski AJ, Harvey M, Fulcher N, de Oliveira C, McCunn P, Donison N, Bartha R, Schmid S, Strong MJ, Volkening K. Synergistic toxicity in an in vivo model of neurodegeneration through the co-expression of human TDP-43 M337V and tau T175D protein. Acta Neuropathol Commun 2019; 7:170. [PMID: 31703746 PMCID: PMC6839082 DOI: 10.1186/s40478-019-0816-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 09/22/2019] [Indexed: 02/08/2023] Open
Abstract
Although it has been suggested that the co-expression of multiple pathological proteins associated with neurodegeneration may act synergistically to induce more widespread neuropathology, experimental evidence of this is sparse. We have previously shown that the expression of Thr175Asp-tau (tauT175D) using somatic gene transfer with a stereotaxically-injected recombinant adeno-associated virus (rAAV9) vector induces tau pathology in rat hippocampus. In this study, we have examined whether the co-expression of human tauT175D with mutant human TDP-43 (TDP-43M337V) will act synergistically. Transgenic female Sprague-Dawley rats that inducibly express mutant human TDP-43M337V using the choline acetyltransferase (ChAT) tetracycline response element (TRE) driver with activity modulating tetracycline-controlled transactivator (tTA) were utilized in these studies. Adult rats were injected with GFP-tagged tau protein constructs in a rAAV9 vector through bilateral stereotaxic injection into the hippocampus. Injected tau constructs were: wild-type GFP-tagged 2N4R human tau (tauWT; n = 8), GFP-tagged tauT175D 2N4R human tau (tauT175D, pseudophosphorylated, toxic variant, n = 8), and GFP (control, n = 8). Six months post-injection, mutant TDP-43M337V expression was induced for 30 days. Behaviour testing identified motor deficits within 3 weeks after TDP-43 expression irrespective of tau expression, though social behaviour and sensorimotor gating remained unchanged. Increased tau pathology was observed in the hippocampus of both tauWT and tauT175D expressing rats and tauT175D pathology was increased in the presence of cholinergic neuronal expression of human TDP-43M337V. These data indicate that co-expression of pathological TDP-43 and tau protein exacerbate the pathology associated with either individual protein.
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9
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Amir Mishan M, Rezaei Kanavi M, Shahpasand K, Ahmadieh H. Pathogenic Tau Protein Species: Promising Therapeutic Targets for Ocular Neurodegenerative Diseases. J Ophthalmic Vis Res 2019; 14:491-505. [PMID: 31875105 PMCID: PMC6825701 DOI: 10.18502/jovr.v14i4.5459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 06/11/2019] [Indexed: 12/13/2022] Open
Abstract
Tau is a microtubule-associated protein, which is highly expressed in the central nervous system as well as ocular neurons and stabilizes microtubule structure. It is a phospho-protein being moderately phosphorylated under physiological conditions but its abnormal hyperphosphorylation or some post-phosphorylation modifications would result in a pathogenic condition, microtubule dissociation, and aggregation. The aggregates can induce neuroinflammation and trigger some pathogenic cascades, leading to neurodegeneration. Taking these together, targeting pathogenic tau employing tau immunotherapy may be a promising therapeutic strategy in fighting with cerebral and ocular neurodegenerative disorders.
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Affiliation(s)
- Mohammad Amir Mishan
- Ocular Tissue Engineering Research Center, Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mozhgan Rezaei Kanavi
- Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Koorosh Shahpasand
- Department of Brain and Cognitive Sciences, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Hamid Ahmadieh
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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10
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Franz CK, Joshi D, Daley EL, Grant RA, Dalamagkas K, Leung A, Finan JD, Kiskinis E. Impact of traumatic brain injury on amyotrophic lateral sclerosis: from bedside to bench. J Neurophysiol 2019; 122:1174-1185. [PMID: 31116639 DOI: 10.1152/jn.00572.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the loss of upper and lower motor neurons, which manifests clinically as progressive weakness. Although several epidemiological studies have found an association between traumatic brain injury (TBI) and ALS, there is not a consensus on whether TBI is an ALS risk factor. It may be that it can cause ALS in a subset of susceptible patients, based on a history of repetitive mild TBI and genetic predisposition. This cannot be determined based on clinical observational studies alone. Better preclinical models are necessary to evaluate the effects of TBI on ALS onset and progression. To date, only a small number of preclinical studies have been performed, mainly in the superoxide dismutase 1 transgenic rodents, which, taken together, have mixed results and notable methodological limitations. The more recent incorporation of additional animal models such as Drosophila flies, as well as patient-induced pluripotent stem cell-derived neurons, should facilitate a better understanding of a potential functional interaction between TBI and ALS.
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Affiliation(s)
- Colin K Franz
- Biologics Laboratory, Shirley Ryan AbilityLab, Chicago, Illinois.,Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois.,The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Divya Joshi
- Biologics Laboratory, Shirley Ryan AbilityLab, Chicago, Illinois
| | - Elizabeth L Daley
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Rogan A Grant
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Kyriakos Dalamagkas
- Department of Physical Medicine and Rehabilitation, McGovern Medical School, TIRR Memorial Hermann, Houston, Texas
| | - Audrey Leung
- Biologics Laboratory, Shirley Ryan AbilityLab, Chicago, Illinois.,Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - John D Finan
- Department of Neurosurgery, NorthShore University HealthSystem, Evanston, Illinois
| | - Evangelos Kiskinis
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois.,Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
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11
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Moszczynski AJ, Hintermayer MA, Strong MJ. Phosphorylation of Threonine 175 Tau in the Induction of Tau Pathology in Amyotrophic Lateral Sclerosis-Frontotemporal Spectrum Disorder (ALS-FTSD). A Review. Front Neurosci 2018; 12:259. [PMID: 29731706 PMCID: PMC5919950 DOI: 10.3389/fnins.2018.00259] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 04/04/2018] [Indexed: 11/17/2022] Open
Abstract
Approximately 50–60% of all patients with amyotrophic lateral sclerosis (ALS) will develop a deficit of frontotemporal function, ranging from frontotemporal dementia (FTD) to one or more deficits of neuropsychological, speech or language function which are collectively known as the frontotemporal spectrum disorders of ALS (ALS-FTSD). While the neuropathology underlying these disorders is most consistent with a widespread alteration in the metabolism of transactive response DNA-binding protein 43 (TDP-43), in both ALS with cognitive impairment (ALSci) and ALS with FTD (ALS-FTD; also known as MND-FTD) there is evidence for alterations in the metabolism of the microtubule associated protein tau. This alteration in tau metabolism is characterized by pathological phosphorylation at residue Thr175 (pThr175 tau) which in vitro is associated with activation of GSK3β (pTyr216GSK3β), phosphorylation of Thr231tau, and the formation of cytoplasmic inclusions with increased rates of cell death. This putative pathway of pThr175 induction of pThr231 and the formation of pathogenic tau inclusions has been recently shown to span a broad range of tauopathies, including chronic traumatic encephalopathy (CTE) and CTE in association with ALS (CTE-ALS). This pathway can be experimentally triggered through a moderate traumatic brain injury, suggesting that it is a primary neuropathological event and not secondary to a more widespread neuronal dysfunction. In this review, we discuss the neuropathological underpinnings of the postulate that ALS is associated with a tauopathy which manifests as a FTSD, and examine possible mechanisms by which phosphorylation at Thr175tau is induced. We hypothesize that this might lead to an unfolding of the hairpin structure of tau, activation of GSK3β and pathological tau fibril formation through the induction of cis-Thr231 tau conformers. A potential role of TDP-43 acting synergistically with pathological tau metabolism is proposed.
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Affiliation(s)
- Alexander J Moszczynski
- Molecular Medicine Research Group, Schulich School of Medicine & Dentistry, Robarts Research Institute, Western University, London, ON, Canada
| | - Matthew A Hintermayer
- Molecular Medicine Research Group, Schulich School of Medicine & Dentistry, Robarts Research Institute, Western University, London, ON, Canada
| | - Michael J Strong
- Molecular Medicine Research Group, Schulich School of Medicine & Dentistry, Robarts Research Institute, Western University, London, ON, Canada.,Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
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Synapse loss in the prefrontal cortex is associated with cognitive decline in amyotrophic lateral sclerosis. Acta Neuropathol 2018; 135:213-226. [PMID: 29273900 PMCID: PMC5773656 DOI: 10.1007/s00401-017-1797-4] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/14/2017] [Accepted: 12/15/2017] [Indexed: 11/23/2022]
Abstract
In addition to motor neurone degeneration, up to 50% of amyotrophic lateral sclerosis (ALS) patients present with cognitive decline. Understanding the neurobiological changes underlying these cognitive deficits is critical, as cognitively impaired patients exhibit a shorter survival time from symptom onset. Given the pathogenic role of synapse loss in other neurodegenerative diseases in which cognitive decline is apparent, such as Alzheimer’s disease, we aimed to assess synaptic integrity in the ALS brain. Here, we have applied a unique combination of high-resolution imaging of post-mortem tissue with neuropathology, genetic screening and cognitive profiling of ALS cases. Analyses of more than 1 million synapses using two complimentary high-resolution techniques (electron microscopy and array tomography) revealed a loss of synapses from the prefrontal cortex of ALS patients. Importantly, synapse loss was significantly greater in cognitively impaired cases and was not due to cortical atrophy, nor associated with dementia-associated neuropathology. Interestingly, we found a trend between pTDP-43 pathology and synapse loss in the frontal cortex and discovered pTDP-43 puncta at a subset of synapses in the ALS brains. From these data, we postulate that synapse loss in the prefrontal cortex represents an underlying neurobiological substrate of cognitive decline in ALS.
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13
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Moszczynski AJ, Strong W, Xu K, McKee A, Brown A, Strong MJ. Pathologic Thr 175 tau phosphorylation in CTE and CTE with ALS. Neurology 2018; 90:e380-e387. [PMID: 29298849 PMCID: PMC5791789 DOI: 10.1212/wnl.0000000000004899] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 10/22/2017] [Indexed: 12/14/2022] Open
Abstract
Objective To investigate whether chronic traumatic encephalopathy (CTE) and CTE with amyotrophic lateral sclerosis (CTE-ALS) exhibit features previously observed in other tauopathies of pathologic phosphorylation of microtubule-associated protein tau at Thr175 (pThr175 tau) and Thr231 (pThr231 tau), and glycogen synthase kinase–3β (GSK3β) activation, and whether these pathologic features are a consequence of traumatic brain injury (TBI). Methods Tau isoform expression was assayed by western blot in 6 stage III CTE cases. We also used immunohistochemistry to analyze 5 cases each of CTE, CTE-ALS, and 5 controls for expression of activated GSK3β, pThr175 tau, pThr231 tau, and oligomerized tau within spinal cord tissue and hippocampus. Using a rat model of moderate TBI, we assessed tau pathology and phospho-GSK3β expression at 3 months postinjury. Results CTE and CTE-ALS are characterized by the presence of all 6 tau isoforms in both soluble and insoluble tau isolates. Activated GSK3β, pThr175 tau, pThr231 tau, and oligomerized tau protein expression was observed in hippocampal neurons and spinal motor neurons. We observed tau neuronal pathology (fibrillar inclusions and axonal damage) and increased levels of pThr175 tau and activated GSK3β in moderate TBI rats. Conclusions Pathologic phosphorylation of tau at Thr175 and Thr231 and activation of GSK3β are features of the tauopathy of CTE and CTE-ALS. These features can be replicated in an animal model of moderate TBI.
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Affiliation(s)
- Alexander J Moszczynski
- From the Molecular Medicine Research Group, Robarts Research Institute (A.J.M., W.S., K.X., A.B., M.J.S.), and Department of Clinical Neurological Sciences (M.J.S.), Schulich School of Medicine & Dentistry, Western University, Canada; and VA Boston Healthcare System, Boston University Alzheimer's Disease and CTE Center (A.M.), Boston University School of Medicine, MA
| | - Wendy Strong
- From the Molecular Medicine Research Group, Robarts Research Institute (A.J.M., W.S., K.X., A.B., M.J.S.), and Department of Clinical Neurological Sciences (M.J.S.), Schulich School of Medicine & Dentistry, Western University, Canada; and VA Boston Healthcare System, Boston University Alzheimer's Disease and CTE Center (A.M.), Boston University School of Medicine, MA
| | - Kathy Xu
- From the Molecular Medicine Research Group, Robarts Research Institute (A.J.M., W.S., K.X., A.B., M.J.S.), and Department of Clinical Neurological Sciences (M.J.S.), Schulich School of Medicine & Dentistry, Western University, Canada; and VA Boston Healthcare System, Boston University Alzheimer's Disease and CTE Center (A.M.), Boston University School of Medicine, MA
| | - Ann McKee
- From the Molecular Medicine Research Group, Robarts Research Institute (A.J.M., W.S., K.X., A.B., M.J.S.), and Department of Clinical Neurological Sciences (M.J.S.), Schulich School of Medicine & Dentistry, Western University, Canada; and VA Boston Healthcare System, Boston University Alzheimer's Disease and CTE Center (A.M.), Boston University School of Medicine, MA
| | - Arthur Brown
- From the Molecular Medicine Research Group, Robarts Research Institute (A.J.M., W.S., K.X., A.B., M.J.S.), and Department of Clinical Neurological Sciences (M.J.S.), Schulich School of Medicine & Dentistry, Western University, Canada; and VA Boston Healthcare System, Boston University Alzheimer's Disease and CTE Center (A.M.), Boston University School of Medicine, MA
| | - Michael J Strong
- From the Molecular Medicine Research Group, Robarts Research Institute (A.J.M., W.S., K.X., A.B., M.J.S.), and Department of Clinical Neurological Sciences (M.J.S.), Schulich School of Medicine & Dentistry, Western University, Canada; and VA Boston Healthcare System, Boston University Alzheimer's Disease and CTE Center (A.M.), Boston University School of Medicine, MA.
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Takeda T. Possible concurrence of TDP-43, tau and other proteins in amyotrophic lateral sclerosis/frontotemporal lobar degeneration. Neuropathology 2017; 38:72-81. [PMID: 28960544 DOI: 10.1111/neup.12428] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/15/2017] [Accepted: 08/15/2017] [Indexed: 12/11/2022]
Abstract
Transactivation response DNA-binding protein 43 kDa (TDP-43) has been regarded as a major component of ubiquitin-positive/tau-negative inclusions of motor neurons and the frontotemporal cortices in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Neurofibrillary tangles (NFT), an example of tau-positive inclusions, are biochemically and morphologically distinguished from TDP-43-positive inclusions, and are one of the pathological core features of Alzheimer disease (AD). Although ALS/FTLD and AD are distinct clinical entities, they can coexist in an individual patient. Whether concurrence of ALS/FTLD-TDP-43 and AD-tau is incidental is still controversial, because aging is a common risk factor for ALS/FTLD and AD development. Indeed, it remains unclear whether the pathogenesis of ALS/FTLD is a direct causal link to tau accumulation. Recent studies suggested that AD pathogenesis could cause the accumulation of TDP-43, while abnormal TDP-43 accumulation could also lead to abnormal tau expression. Overlapping presence of TDP-43 and tau, when observed in a brain during autopsy, should attract attention, and should initiate the search for the pathological substrate for this abnormal protein accumulation. In addition to tau, other proteins including α-synuclein and amyloid β should be also taken into account as candidates for an interaction with TDP-43. Awareness of a possible comorbidity between TDP-43, tau and other proteins in patients with ALS/FTLD will be useful for our understanding of the influence of these proteins on the disease development and its clinical manifestation.
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Affiliation(s)
- Takahiro Takeda
- Department of Neurology, Tokyo Women's Medical University, Tokyo, Japan
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15
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Volkening K, Strong WL, Seaton S, Yang W, Strong MJ. C9orf72 mutations do not influence the tau signature of amyotrophic lateral sclerosis with cognitive impairment (ALSci). Amyotroph Lateral Scler Frontotemporal Degener 2017; 18:549-554. [PMID: 28562075 DOI: 10.1080/21678421.2017.1332075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE C9orf72 mutations are associated with amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD) and ALS-FTD. In addition to ALS-FTD, ALS patients may develop a spectrum of neuropsychological and neuropsychiatric deficits including ALS with cognitive impairment (ALSci). Here we examine the extent to which C9orf72 mutations are associated with ALSci and whether this alters the tau molecular signature. METHODS We identified 16 ALSci cases within a post-mortem archive of 94 fully genotyped ALS cases, eight of which harboured a C9orf72 mutation, in addition to three cognitively-intact ALS cases with a C9orf72 mutation. Tau was fractionated into soluble and insoluble fractions, with or without dephosphorylation, and immunoblots for tau phospho-isoforms performed. RESULTS Regardless of cognitive state or the presence of C9orf72 mutation, all ALS cases demonstrated six tau isoforms in both soluble and insoluble tau isolates. This pattern was unaffected by dephosphorylation. pThr175tau isoforms, a molecular signature of ALSci, were present regardless of C9orf72 genetic status. The pathognomic paired helical triplet in the insoluble tau fraction of Alzheimer's disease was not observed, regardless of cognitive or C9orf72 status. CONCLUSIONS These findings suggest that the presence of a C9orf72 mutation does not influence the tau signature of ALS or ALSci.
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Affiliation(s)
- Kathryn Volkening
- a Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada and.,b Clinical Neurological Sciences, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada
| | - Wendy L Strong
- a Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada and
| | - Shauntel Seaton
- a Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada and
| | - Wencheng Yang
- a Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada and
| | - Michael J Strong
- a Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada and.,b Clinical Neurological Sciences, Schulich School of Medicine & Dentistry , University of Western Ontario , London , Ontario , Canada
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Brady ST, Morfini GA. Regulation of motor proteins, axonal transport deficits and adult-onset neurodegenerative diseases. Neurobiol Dis 2017; 105:273-282. [PMID: 28411118 DOI: 10.1016/j.nbd.2017.04.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/17/2017] [Accepted: 04/10/2017] [Indexed: 01/07/2023] Open
Abstract
Neurons affected in a wide variety of unrelated adult-onset neurodegenerative diseases (AONDs) typically exhibit a "dying back" pattern of degeneration, which is characterized by early deficits in synaptic function and neuritic pathology long before neuronal cell death. Consistent with this observation, multiple unrelated AONDs including Alzheimer's disease, Parkinson's disease, Huntington's disease, and several motor neuron diseases feature early alterations in kinase-based signaling pathways associated with deficits in axonal transport (AT), a complex cellular process involving multiple intracellular trafficking events powered by microtubule-based motor proteins. These pathogenic events have important therapeutic implications, suggesting that a focus on preservation of neuronal connections may be more effective to treat AONDs than addressing neuronal cell death. While the molecular mechanisms underlying AT abnormalities in AONDs are still being analyzed, evidence has accumulated linking those to a well-established pathological hallmark of multiple AONDs: altered patterns of neuronal protein phosphorylation. Here, we present a short overview on the biochemical heterogeneity of major motor proteins for AT, their regulation by protein kinases, and evidence revealing cell type-specific AT specializations. When considered together, these findings may help explain how independent pathogenic pathways can affect AT differentially in the context of each AOND.
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Affiliation(s)
- Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA 02543, USA.
| | - Gerardo A Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA 02543, USA.
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Moszczynski AJ, Yang W, Hammond R, Ang LC, Strong MJ. Threonine 175, a novel pathological phosphorylation site on tau protein linked to multiple tauopathies. Acta Neuropathol Commun 2017; 5:6. [PMID: 28077166 PMCID: PMC5225652 DOI: 10.1186/s40478-016-0406-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 12/15/2016] [Indexed: 12/13/2022] Open
Abstract
Microtubule associated protein tau (tau) deposition is associated with a spectrum of neurodegenerative diseases collectively termed tauopathies. We have previously shown that amyotrophic lateral sclerosis (ALS) with cognitive impairment (ALSci) is associated with tau phosphorylation at Thr175 and that this leads to activation of GSK3β which then induces phosphorylation at tau Thr231. This latter step leads to dissociation of tau from microtubules and pathological tau fibril formation. To determine the extent to which this pathway is unique to ALS, we have investigated the expression of pThr175 tau and pThr231 tau across a range of frontotemporal degenerations. Representative sections from the superior frontal cortex, anterior cingulate cortex (ACC), amygdala, hippocampal formation, basal ganglia, and substantia nigra were selected from neuropathologically confirmed cases of Alzheimer’s disease (AD; n = 3), vascular dementia (n = 2), frontotemporal lobar degeneration (FTLD; n = 4), ALS (n = 5), ALSci (n = 6), Parkinson’s disease (PD; n = 5), corticobasal degeneration (CBD; n = 2), diffuse Lewy body dementia (DLBD; n = 2), mixed DLBD (n = 3), multisystem atrophy (MSA; n = 6) and Pick’s disease (n = 1) and three neuropathologically-normal control groups aged 50–60 (n = 6), 60–70 (n = 6) and 70–80 (n = 8). Sections were examined using a panel of phospho-tau antibodies (pSer208,210, pThr217, pThr175, pThr231, pSer202 and T22 (oligomeric tau)). Across diseases, phospho-tau load was most prominent in layers II/III of the entorhinal cortex, amygdala and hippocampus. This is in contrast to the preferential deposition of phospho-tau in the ACC and frontal cortex in ALSci. Controls showed pThr175 tau expression only in the 7th decade of life and only in the presence of tau pathology and tau oligomers. With the exception of DLBD, we observed pThr175 co-localizing with pThr231 in the same cell populations as T22 positivity. This suggests that this pathway may be a common mechanism of toxicity across the tauopathies.
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18
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Vintilescu CR, Afreen S, Rubino AE, Ferreira A. The Neurotoxic TAU 45-230 Fragment Accumulates in Upper and Lower Motor Neurons in Amyotrophic Lateral Sclerosis Subjects. Mol Med 2016; 22:477-486. [PMID: 27496042 PMCID: PMC5072411 DOI: 10.2119/molmed.2016.00095] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 07/23/2016] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive and lethal neurodegenerative disease characterized by the loss of upper and lower motor neurons leading to muscle paralysis in affected individuals. Numerous mechanisms have been implicated in the death of these neurons. However, the pathobiology of this disease has not been completely elucidated. In the present study, we investigated to what extent tau cleavage and the generation of the neurotoxic tau45-230 fragment is associated with ALS. Quantitative Western blot analysis indicated that high levels of tau45-230 accumulated in lumbar and cervical spinal cord specimens obtained from ALS subjects. This neurotoxic tau fragment was also detected in ALS upper motor neurons located in the precentral gyrus. Our results also showed that tau45-230 aggregates were present in the spinal cord of ALS patients. On the other hand, this neurotoxic fragment was not generated in a mouse model of a familial form of this disease. Together, these results suggest a potential role for this neurotoxic tau fragment in the mechanisms leading to the degeneration of motor neurons in the context of sporadic ALS.
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Affiliation(s)
- Claudia R Vintilescu
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, IL 60611
| | - Sana Afreen
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, IL 60611
| | - Ashlee E Rubino
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, IL 60611
| | - Adriana Ferreira
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, IL 60611
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Clark JA, Yeaman EJ, Blizzard CA, Chuckowree JA, Dickson TC. A Case for Microtubule Vulnerability in Amyotrophic Lateral Sclerosis: Altered Dynamics During Disease. Front Cell Neurosci 2016; 10:204. [PMID: 27679561 PMCID: PMC5020100 DOI: 10.3389/fncel.2016.00204] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/15/2016] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an aggressive multifactorial disease converging on a common pathology: the degeneration of motor neurons (MNs), their axons and neuromuscular synapses. This vulnerability and dysfunction of MNs highlights the dependency of these large cells on their intracellular machinery. Neuronal microtubules (MTs) are intracellular structures that facilitate a myriad of vital neuronal functions, including activity dependent axonal transport. In ALS, it is becoming increasingly apparent that MTs are likely to be a critical component of this disease. Not only are disruptions in this intracellular machinery present in the vast majority of seemingly sporadic cases, recent research has revealed that mutation to a microtubule protein, the tubulin isoform TUBA4A, is sufficient to cause a familial, albeit rare, form of disease. In both sporadic and familial disease, studies have provided evidence that microtubule mediated deficits in axonal transport are the tipping point for MN survivability. Axonal transport deficits would lead to abnormal mitochondrial recycling, decreased vesicle and mRNA transport and limited signaling of key survival factors from the neurons peripheral synapses, causing the characteristic peripheral "die back". This disruption to microtubule dependant transport in ALS has been shown to result from alterations in the phenomenon of microtubule dynamic instability: the rapid growth and shrinkage of microtubule polymers. This is accomplished primarily due to aberrant alterations to microtubule associated proteins (MAPs) that regulate microtubule stability. Indeed, the current literature would argue that microtubule stability, particularly alterations in their dynamics, may be the initial driving force behind many familial and sporadic insults in ALS. Pharmacological stabilization of the microtubule network offers an attractive therapeutic strategy in ALS; indeed it has shown promise in many neurological disorders, ALS included. However, the pathophysiological involvement of MTs and their functions is still poorly understood in ALS. Future investigations will hopefully uncover further therapeutic targets that may aid in combating this awful disease.
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Affiliation(s)
- Jayden A Clark
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Elise J Yeaman
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Catherine A Blizzard
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Jyoti A Chuckowree
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Tracey C Dickson
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
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Cavaleri F. Review of Amyotrophic Lateral Sclerosis, Parkinson’s and Alzheimer’s diseases helps further define pathology of the novel paradigm for Alzheimer’s with heavy metals as primary disease cause. Med Hypotheses 2015; 85:779-90. [DOI: 10.1016/j.mehy.2015.10.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/25/2015] [Accepted: 10/11/2015] [Indexed: 01/07/2023]
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Moszczynski AJ, Gohar M, Volkening K, Leystra-Lantz C, Strong W, Strong MJ. Thr175-phosphorylated tau induces pathologic fibril formation via GSK3β-mediated phosphorylation of Thr231 in vitro. Neurobiol Aging 2014; 36:1590-9. [PMID: 25573097 DOI: 10.1016/j.neurobiolaging.2014.12.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 11/11/2014] [Accepted: 12/03/2014] [Indexed: 12/13/2022]
Abstract
We have previously shown that amyotrophic lateral sclerosis with cognitive impairment can be characterized by pathologic inclusions of microtubule-associated protein tau (tau) phosphorylated at Thr(175) (pThr(175)) in association with GSK3β activation. We have now examined whether pThr(175) induces GSK3β activation and whether this leads to pathologic fibril formation through Thr(231) phosphorylation. Seventy-two hours after transfection of Neuro2A cells with pseudophosphorylated green fluorescent protein-tagged 2N4R tau (Thr(175)Asp), phosphorylated kinase glycogen synthase kinase 3 beta (active GSK3β) levels were significantly increased as was pathologic fibril formation and cell death. Treatment with each of 4 GSK3β inhibitors or small hairpin RNA knockdown of GSK3β abolished fibril formation and prevented cell death. Inhibition of Thr(231) phosphorylation (Thr(231)Ala) prevented pathologic tau fibril formation, regardless of Thr(175) state, whereas Thr(231)Asp (pseudophosphorylated at Thr(231)) developed pathologic tau fibrils. Ser(235) mutations did not affect fibril formation, indicating an unprimed mechanism of Thr(231) phosphorylation. These findings suggest a mechanism of tau pathology by which pThr(175) induces GSK3β phosphorylation of Thr(231) leading to fibril formation, indicating a potential therapeutic avenue for amyotrophic lateral sclerosis with cognitive impairment.
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Affiliation(s)
- Alexander J Moszczynski
- Graduate Program in Neuroscience, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - May Gohar
- Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - Kathryn Volkening
- Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada; Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - Cheryl Leystra-Lantz
- Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - Wendy Strong
- Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - Michael J Strong
- Graduate Program in Neuroscience, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada; Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada.
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Droppelmann CA, Campos-Melo D, Ishtiaq M, Volkening K, Strong MJ. RNA metabolism in ALS: When normal processes become pathological. Amyotroph Lateral Scler Frontotemporal Degener 2014; 15:321-36. [DOI: 10.3109/21678421.2014.881377] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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The genetics and neuropathology of amyotrophic lateral sclerosis. Acta Neuropathol 2012; 124:339-52. [PMID: 22903397 DOI: 10.1007/s00401-012-1022-4] [Citation(s) in RCA: 276] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 07/16/2012] [Accepted: 07/18/2012] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of motor neurons leading to death from respiratory failure within about 3 years of symptom onset. A family history of ALS is obtained in about 5 % but the distinction between familial and apparently sporadic ALS is artificial and genetic factors play a role in all types. For several years, only one gene was known to have a role in ALS pathogenesis, SOD1. In the last few years there has been a rapid advance in our genetic knowledge of the causes of ALS, and the relationship of the genetic subtypes with pathological subtypes and clinical phenotype. Mutations in the gene for TDP-43 protein, TARDBP, highlight this, with pathology mimicking closely that found in other types of ALS, and a phenotypic spectrum that includes frontotemporal dementia. Mutations in the FUS gene, closely related to TDP-43, lead to a similar clinical phenotype but distinct pathology, so that the three pathological groups represented by SOD1, TARDBP, and FUS are distinct. In this review, we explore the genetic architecture of ALS, highlight some of the genes implicated in pathogenesis, and describe their phenotypic range and overlap with other diseases.
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Cipresso P, Carelli L, Solca F, Meazzi D, Meriggi P, Poletti B, Lulé D, Ludolph AC, Silani V, Riva G. The use of P300-based BCIs in amyotrophic lateral sclerosis: from augmentative and alternative communication to cognitive assessment. Brain Behav 2012; 2:479-98. [PMID: 22950051 PMCID: PMC3432970 DOI: 10.1002/brb3.57] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2011] [Revised: 03/06/2012] [Accepted: 03/13/2012] [Indexed: 12/11/2022] Open
Abstract
The use of augmentative and alternative communication (AAC) tools in patients with amyotrophic lateral sclerosis (ALS), as effective means to compensate for the progressive loss of verbal and gestural communication, has been deeply investigated in the recent literature. The development of advanced AAC systems, such as eye-tracking (ET) and brain-computer interface (BCI) devices, allowed to bypass the important motor difficulties present in ALS patients. In particular, BCIs could be used in moderate to severe stages of the disease, since they do not require preserved ocular-motor ability, which is necessary for ET applications. Furthermore, some studies have proved the reliability of BCIs, regardless of the severity of the disease and the level of physical decline. However, the use of BCI in ALS patients still shows some limitations, related to both technical and neuropsychological issues. In particular, a range of cognitive deficits in most ALS patients have been observed. At the moment, no effective verbal-motor free measures are available for the evaluation of ALS patients' cognitive integrity; BCIs could offer a new possibility to administer cognitive tasks without the need of verbal or motor responses, as highlighted by preliminary studies in this field. In this review, we outline the essential features of BCIs systems, considering advantages and challenges of these tools with regard to ALS patients and the main applications developed in this field. We then outline the main findings with regard to cognitive deficits observed in ALS and some preliminary attempts to evaluate them by means of BCIs. The definition of specific cognitive profiles could help to draw flexible approaches tailored on patients' needs. It could improve BCIs efficacy and reduce patients' efforts. Finally, we handle the open question, represented by the use of BCIs with totally locked in patients, who seem unable to reliably learn to use such tool.
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Affiliation(s)
- Pietro Cipresso
- Applied Technology for Neuro‐Psychology Lab, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Laura Carelli
- Department of Neurology and Laboratory of Neuroscience ‐ “Dino Ferrari” Center ‐ Università degli Studi di Milano ‐ IRCCS Istituto Auxologico Italiano, Milano, Italy
| | - Federica Solca
- Department of Neurology and Laboratory of Neuroscience ‐ “Dino Ferrari” Center ‐ Università degli Studi di Milano ‐ IRCCS Istituto Auxologico Italiano, Milano, Italy
| | - Daniela Meazzi
- Applied Technology for Neuro‐Psychology Lab, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Paolo Meriggi
- Polo Tecnologico–Biomedical Technology Department, Fondazione Don Carlo Gnocchi Onlus, Milano, Italy
| | - Barbara Poletti
- Department of Neurology and Laboratory of Neuroscience ‐ “Dino Ferrari” Center ‐ Università degli Studi di Milano ‐ IRCCS Istituto Auxologico Italiano, Milano, Italy
| | - Dorothée Lulé
- Department of Neurology ‐ University of Ulm, Ulm, Germany
| | | | - Vincenzo Silani
- Department of Neurology and Laboratory of Neuroscience ‐ “Dino Ferrari” Center ‐ Università degli Studi di Milano ‐ IRCCS Istituto Auxologico Italiano, Milano, Italy
| | - Giuseppe Riva
- Applied Technology for Neuro‐Psychology Lab, IRCCS Istituto Auxologico Italiano, Milan, Italy
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Yang W, Strong MJ. Widespread neuronal and glial hyperphosphorylated tau deposition in ALS with cognitive impairment. ACTA ACUST UNITED AC 2012; 13:178-93. [PMID: 22214313 DOI: 10.3109/17482968.2011.622405] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although the biological basis of frontotemporal syndromes associated with amyotrophic lateral sclerosis (ALS) is considered to be altered metabolism of TDP-43, in ALS with cognitive impairment (ALSci) the metabolism of tau protein is also altered. This includes neuronal hyperphosphorylation (pThr(175)). Using novel polyclonal phospho-tau antibodies (pSer(208, 210), pThr(217) and pThr(175)) and antibodies directed against PHF tau (pSer(202)), TDP-43 or ubiquitin, we characterized tau deposition in ALS and ALSci. In ALS, we observed pThr(175) tau immunoreactive intraneuronal and neuritic aggregates throughout the amygdala and entorhinal cortex. In ALSci, this extended to the anterior cingulate gyrus, superior frontal cortex and substantia nigra. The pThr(217) antibody detected widespread astrocytic tau deposition, including punctuate or fibrillary aggregates, or intensely immunoreactive tufted astrocytes in the superior frontal cortex, anterior cingulate gyrus, entorhinal cortex, amygdala and basal ganglia of ALS. In ALSci, a similar but more widely distributed pThr(217) pathology was observed. There was no correlation between the extent of pathological tau deposition and TDP-43 pathology, although nuclear TDP-43 immunoreactivity was absent in neurons with tau pathology. In conclusion, ALSci is unique in possessing both tau and TDP-43 pathology. The presence of widespread astrocytic tau pathology suggests that ALSci may initially be characterized by astrocytic pathology.
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Affiliation(s)
- Wencheng Yang
- Robarts Research Institute, The University of Western Ontario, Canada
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Xu YF, Zhang YJ, Lin WL, Cao X, Stetler C, Dickson DW, Lewis J, Petrucelli L. Expression of mutant TDP-43 induces neuronal dysfunction in transgenic mice. Mol Neurodegener 2011; 6:73. [PMID: 22029574 PMCID: PMC3216869 DOI: 10.1186/1750-1326-6-73] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 10/26/2011] [Indexed: 12/12/2022] Open
Abstract
Background Abnormal distribution, modification and aggregation of transactivation response DNA-binding protein 43 (TDP-43) are the hallmarks of multiple neurodegenerative diseases, especially frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) and amyotrophic lateral sclerosis (ALS). Researchers have identified 44 mutations in the TARDBP gene that encode TDP-43 as causative for cases of sporadic and familial ALS http://www.molgen.ua.ac.be/FTDMutations/. Certain mutant forms of TDP-43, such as M337V, are associated with increased low molecular weight (LMW) fragments compared to wild-type (WT) TDP-43 and cause neuronal apoptosis and developmental delay in chick embryos. Such findings support a direct link between altered TDP-43 function and neurodegeneration. Results To explore the pathogenic properties of the M337V mutation, we generated and characterized two mouse lines expressing human TDP-43 (hTDP-43M337V) carrying this mutation. hTDP-43M337V was expressed primarily in the nuclei of neurons in the brain and spinal cord, and intranuclear and cytoplasmic phosphorylated TDP-43 aggregates were frequently detected. The levels of TDP-43 LMW products of ~25 kDa and ~35 kDa species were also increased in the transgenic mice. Moreover, overexpression of hTDP-43M337V dramatically down regulated the levels of mouse TDP-43 (mTDP-43) protein and RNA, indicating TDP-43 levels are tightly controlled in mammalian systems. TDP-43M337V mice displayed reactive gliosis, widespread ubiquitination, chromatolysis, gait abnormalities, and early lethality. Abnormal cytoplasmic mitochondrial aggregates and abnormal phosphorylated tau were also detected in the mice. Conclusion Our novel TDP-43M337V mouse model indicates that overexpression of hTDP-43M337V alone is toxic in vivo. Because overexpression of hTDP-43 in wild-type TDP-43 and TDP-43M337V mouse models produces similar phenotypes, the mechanisms causing pathogenesis in the mutant model remain unknown. However, our results suggest that overexpression of the hTDP-43M337V can cause neuronal dysfunction due to its effect on a number of cell organelles and proteins, such as mitochondria and TDP-43, that are critical for neuronal activity. The mutant model will serve as a valuable tool in the development of future studies designed to uncover pathways associated with TDP-43 neurotoxicity and the precise roles TDP-43 RNA targets play in neurodegeneration.
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Affiliation(s)
- Ya-Fei Xu
- Department of Neuroscience, Mayo Clinic, Jacksonville, 32224, USA
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Lack of effect of methylene blue in the SOD1 G93A mouse model of amyotrophic lateral sclerosis. PLoS One 2011; 6:e23141. [PMID: 21998625 PMCID: PMC3188547 DOI: 10.1371/journal.pone.0023141] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 07/12/2011] [Indexed: 12/11/2022] Open
Abstract
Background Methylene blue (MB) is a drug with a long history and good safety profile, and with recently-described features desirable in a treatment for ALS. Methodology/Principal Findings We tested oral MB in inbred high-copy number SOD1 G93A mice, at 25 mg/kg/day beginning at 45 days of age. We measured disease onset, progression, and survival. There was no difference in disease onset between MB-treated mice and controls, although subgroup analysis showed a modest but statistically significant delay in disease onset in MB-treated female mice only (control 122±10.2 versus MB 129±10.0 days). MB-treated mice of both sexes spent more time in less severe stages of disease, and less time in later, more severe stages of disease. There was a non-significant trend to longer survival in MB-treated animals (control males reached endpoint at 161±14.1 days, versus 166±10.0 days for MB-treated animals, and control females reached endpoint at 171±6.2 days versus 173±13.4 days for MB-treated animals). Conclusions/Significance In spite of a strong theoretical rationale, MB had no significant effects on onset or survival in the inbred SOD1 G93A mouse model of ALS.
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Strong MJ, Yang W. The frontotemporal syndromes of ALS. Clinicopathological correlates. J Mol Neurosci 2011; 45:648-55. [PMID: 21809041 DOI: 10.1007/s12031-011-9609-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 07/20/2011] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is increasingly recognized to be a syndromic disorder in which the degeneration of motor neurons is frequently accompanied by a range of syndromes reflective of frontotemporal dysfunction, including a behavioural or cognitive syndrome, a dysexecutive syndrome or a frontotemporal dementia. Both sporadic and familial variants of ALS can be affected. The anatomic substrate of each is a frontotemporal lobar degeneration (FTLD) characterized by superficial linear spongiosus, atrophy and neuronal loss, and both astrocytic and neuronal deposition of TDP-43 as pathological inclusions. Largely unrecognized however is the extent of alterations in tau protein metabolism, particularly in cognitively impaired patients (ALSci). This includes hyper-phosphorylation (pThr(175)) and tau phosphatase resistance, increased fibril formation ex vivo of tau isolated from ALSci and tau immunoreactive aggregates in neurons, dystrophic neurites and astrocytes. In this article, we will review the contemporary clinical, genetic and neuropathological characteristics of the frontotemporal syndromes of ALS and propose that as opposed to being a FTLD in which TDP-43 is the primary disease protein (FTLD-TDP) and that the frontotemporal syndromes of ALS represent a hybrid of both TDP-43 and tau pathology.
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Affiliation(s)
- Michael Joseph Strong
- Robarts Research Institute, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada.
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29
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Guest WC, Silverman JM, Pokrishevsky E, O'Neill MA, Grad LI, Cashman NR. Generalization of the prion hypothesis to other neurodegenerative diseases: an imperfect fit. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2011; 74:1433-1459. [PMID: 22043906 DOI: 10.1080/15287394.2011.618967] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Protein misfolding diseases have been classically understood as diffuse errors in protein folding, with misfolded protein arising autonomously throughout a tissue due to a pathologic stressor. The field of prion science has provided an alternative mechanism whereby a seed of pathologically misfolded protein, arising exogenously or through a rare endogenous structural fluctuation, yields a template to catalyze misfolding of the native protein. The misfolded protein may then spread intercellularly to communicate the misfold to adjacent areas and ultimately infect a whole tissue. Mounting evidence implicates a prion-like process in the propagation of several neurodegenerative diseases, including Alzheimer's, Parkinson's, Huntington's, amyotrophic lateral sclerosis, and the tauopathies. However, the parallels between the events observed in these conditions and those in prion disease are often incomplete. The aim of this review was to examine the current state of knowledge concerning the mechanisms of protein misfolding and aggregation for neurodegeneration-associated proteins. In addition, possible methods of intercellular spread are described that focus on the hypothesis that released microvesicles function as misfolded protein delivery vehicles, and the therapeutic options enabled by viewing these diseases from the prion perspective.
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Affiliation(s)
- Will C Guest
- Brain Research Centre, University of British Columbia, Vancouver, BC, Canada
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30
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Kudo LC, Parfenova L, Vi N, Lau K, Pomakian J, Valdmanis P, Rouleau GA, Vinters HV, Wiedau-Pazos M, Karsten SL. Integrative gene-tissue microarray-based approach for identification of human disease biomarkers: application to amyotrophic lateral sclerosis. Hum Mol Genet 2010; 19:3233-53. [PMID: 20530642 DOI: 10.1093/hmg/ddq232] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Advances in genomics and proteomics permit rapid identification of disease-relevant genes and proteins. Challenges include biological differences between animal models and human diseases, high discordance between DNA and protein expression data and a lack of experimental models to study human complex diseases. To overcome some of these limitations, we developed an integrative approach using animal models, postmortem human material and a combination of high-throughput microarray methods to identify novel molecular markers of amyotrophic lateral sclerosis (ALS). We used laser capture microdissection coupled with microarrays to identify early transcriptome changes occurring in spinal cord motor neurons or surrounding glial cells. Two models of familial motor neuron disease, SOD1(G93A) and TAU(P301L), transgenic mice were used at the presymptomatic stage. Identified gene expression changes were predominantly model-specific. However, several genes were regulated in both models. The relevance of identified genes as clinical biomarkers was tested in the peripheral blood transcriptome of presymptomatic SOD1(G93A) animals using custom-designed ALS microarray. To confirm the relevance of identified genes in human sporadic ALS (SALS), selected corresponding protein products were examined by high-throughput immunoassays using tissue microarrays constructed from human postmortem spinal cord tissues. Genes that were identified by these experiments and located within a linkage region associated with familial ALS/frontotemporal dementia were sequenced in several families. This large-scale gene and protein expression study pointing to distinct molecular mechanisms of TAU- and SOD1-induced motor neuron degeneration identified several new SALS-relevant proteins (CNGA3, CRB1, OTUB2, MMP14, SLK, DDX58, RSPO2) and putative blood biomarkers, including Nefh, Prph and Mgll.
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Affiliation(s)
- Lili C Kudo
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
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31
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Abstract
Alzheimer's disease is a progressive neurodegenerative disease for which no cure exists. There is a substantial need for new therapies that offer improved symptomatic benefit and disease-slowing capabilities. In recent decades there has been substantial progress in understanding the molecular and cellular changes associated with Alzheimer's disease pathology. This has resulted in identification of a large number of new drug targets. These targets include, but are not limited to, therapies that aim to prevent production of or remove the amyloid-beta protein that accumulates in neuritic plaques; to prevent the hyperphosphorylation and aggregation into paired helical filaments of the microtubule-associated protein tau; and to keep neurons alive and functioning normally in the face of these pathologic challenges. We provide a review of these targets for drug development.
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Affiliation(s)
- Joshua D Grill
- Mary S. Easton Center for Alzheimer's Disease Research, Deane F. Johnson Center for Neurotherapeutics, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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Pigmented creatine deposits in Amyotrophic Lateral Sclerosis central nervous system tissues identified by synchrotron Fourier Transform Infrared microspectroscopy and X-ray fluorescence spectromicroscopy. Neuroscience 2010; 166:1119-28. [DOI: 10.1016/j.neuroscience.2010.01.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 01/06/2010] [Accepted: 01/08/2008] [Indexed: 11/18/2022]
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Kumari U, Heese K. Cardiovascular dementia - a different perspective. Open Biochem J 2010; 4:29-52. [PMID: 20448820 PMCID: PMC2864432 DOI: 10.2174/1874091x01004010029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2009] [Revised: 01/12/2010] [Accepted: 01/22/2010] [Indexed: 02/08/2023] Open
Abstract
The number of dementia patients has been growing in recent years and dementia represents a significant threat to aging people all over the world. Recent research has shown that the number of people affected by Alzheimer's disease (AD) and dementia is growing at an epidemic pace. The rapidly increasing financial and personal costs will affect the world's economies, health care systems, and many families. Researchers are now exploring a possible connection among AD, vascular dementia (VD), diabetes mellitus (type 2, T2DM) and cardiovascular diseases (CD). This correlation may be due to a strong association of cardiovascular risk factors with AD and VD, suggesting that these diseases share some biologic pathways. Since heart failure is associated with an increased risk of AD and VD, keeping the heart healthy may prove to keep the brain healthy as well. The risk for dementia is especially high when diabetes mellitus is comorbid with severe systolic hypertension or heart disease. In addition, the degree of coronary artery disease (CAD) is independently associated with cardinal neuropathological lesions of AD. Thus, the contribution of T2DM and CD to AD and VD implies that cardiovascular therapies may prove useful in preventing AD and dementia.
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Affiliation(s)
- Udhaya Kumari
- Division of Cell and Molecular Biology, School of Biological Sciences, College of Science, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
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34
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Raggi A, Iannaccone S, Cappa SF. Event-related brain potentials in amyotrophic lateral sclerosis: A review of the international literature. ACTA ACUST UNITED AC 2010; 11:16-26. [DOI: 10.3109/17482960902912399] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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35
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Strong MJ. The syndromes of frontotemporal dysfunction in amyotrophic lateral sclerosis. ACTA ACUST UNITED AC 2009; 9:323-38. [PMID: 18752088 DOI: 10.1080/17482960802372371] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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36
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Axonal stress kinase activation and tau misbehavior induced by kinesin-1 transport defects. J Neurosci 2009; 29:5758-67. [PMID: 19420244 DOI: 10.1523/jneurosci.0780-09.2009] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Many neurodegenerative diseases exhibit axonal pathology, transport defects, and aberrant phosphorylation and aggregation of the microtubule binding protein tau. While mutant tau protein in frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP17) causes aberrant microtubule binding and assembly of tau into filaments, the pathways leading to tau-mediated neurotoxicity in Alzheimer's disease and other neurodegenerative disorders in which tau protein is not genetically modified remain unknown. To test the hypothesis that axonal transport defects alone can cause pathological abnormalities in tau protein and neurodegeneration in the absence of mutant tau or amyloid beta deposits, we induced transport defects by deletion of the kinesin light chain 1 (KLC1) subunit of the anterograde motor kinesin-1. We found that upon aging, early selective axonal transport defects in mice lacking the KLC1 protein (KLC1-/-) led to axonopathies with cytoskeletal disorganization and abnormal cargo accumulation. In addition, increased c-jun N-terminal stress kinase activation colocalized with aberrant tau in dystrophic axons. Surprisingly, swollen dystrophic axons exhibited abnormal tau hyperphosphorylation and accumulation. Thus, directly interfering with axonal transport is sufficient to activate stress kinase pathways initiating a biochemical cascade that drives normal tau protein into a pathological state found in a variety of neurodegenerative disorders including Alzheimer's disease.
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Le Forestier N, Lacomblez L, Meininger V. Syndromes parkinsoniens et sclérose latérale amyotrophique. Rev Neurol (Paris) 2009; 165:15-30. [DOI: 10.1016/j.neurol.2008.02.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2007] [Revised: 08/31/2007] [Accepted: 02/08/2008] [Indexed: 12/11/2022]
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Paladino P, Valentino F, Piccoli T, Piccoli F, La Bella V. Cerebrospinal fluid tau protein is not a biological marker in amyotrophic lateral sclerosis. Eur J Neurol 2008; 16:257-61. [PMID: 19138331 DOI: 10.1111/j.1468-1331.2008.02405.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder leading to progressive motor neuron cell death. Etiopathogenesis is still imperfectly known and much effort have been undertaken to find a biological marker that could help in the early diagnosis and in the monitoring of disease progression. Cerebrospinal fluid (CSF) concentrations of tau, an axonal microtubule-associated protein, have been measured in ALS with levels found increased in some studies and unchanged in others. METHODS Total CSF tau level was assayed in a population of ALS patients (n = 57) and controls (n = 110) using a specific ELISA method. RESULTS No significant differences in the median CSF tau levels between ALS cases and controls were found [ALS: 126 pg/ml (78-222); controls: 112 pg/ml (71-188), P = ns]. In the ALS group, the bulbar-onset patients showed increased CSF tau levels as compared with the spinal-onset cases. These differences might be related to the higher age of the bulbar-onset patients. Further, no correlations were found between CSF tau concentrations and the rate of progression of the disease. CONCLUSIONS These results do not support the hypothesis that total CSF tau protein is a reliable biological marker for ALS.
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Affiliation(s)
- P Paladino
- Department of Neurology and Psychiatry, ALS Clinical Research Center, AOUP-University of Palermo, Palermo, Italy
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39
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Gohar M, Yang W, Strong W, Volkening K, Leystra-Lantz C, Strong MJ. Tau phosphorylation at threonine-175 leads to fibril formation and enhanced cell death: implications for amyotrophic lateral sclerosis with cognitive impairment. J Neurochem 2008; 108:634-43. [PMID: 19046355 DOI: 10.1111/j.1471-4159.2008.05791.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although amyotrophic lateral sclerosis (ALS) can be associated with cognitive impairment (ALSci) as a reflection of frontotemporal lobar degeneration, the basis of this process is unknown. The observation of neuronal and extraneuronal tau deposition in ALSci in addition to a unique tau phosphorylation at Thr175 has suggested that ALSci can be associated with alterations in tau metabolism. We have examined the association between phosphorylation at Thr175 and tau fibril formation. Both soluble and insoluble tau was purified from control, patients with Alzheimer's disease (AD), ALS without cognitive impairment, and ALSci and the tendency to fibril formation assayed ex vivo using the thioflavin S fluorescence assay. The extent of fibril formation was significantly greater in tau derived from ALSci, with ALS-derived tau being intermediate between control and AD-derived tau. Using both Neuro2A and human embryonic kidney (HEK293T) cells, we expressed full-length tau constructs harboring either a pseudophosphorylation at Thr175 (Thr175-Asp-tau), inhibition of Thr175 phosphorylation (Thr175-Ala-tau) or intact tau (wild-type tau). Both tau fibril formation and cell death were significantly enhanced in the presence of Thr175-Asp-tau, regardless of the tau isoform, suggesting that phosphorylation of Thr175 is associated with tau fibril formation in ALSci.
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Affiliation(s)
- May Gohar
- The Robarts Research Institute, The University of Western Ontario, London, Ontario, Canada
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Yang W, Leystra-Lantz C, Strong MJ. Upregulation of GSK3beta expression in frontal and temporal cortex in ALS with cognitive impairment (ALSci). Brain Res 2008; 1196:131-9. [PMID: 18221734 DOI: 10.1016/j.brainres.2007.12.031] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 12/10/2007] [Accepted: 12/12/2007] [Indexed: 11/28/2022]
Abstract
The deposition of highly phosphorylated microtubule-associated tau protein has been observed in ALS with cognitive impairment (ALSci). In these studies, we have examined whether the expression of two candidate protein kinases for mediating tau hyperphosphorylation (GSK3beta or CDK5) are also altered. The expression of GSK, CDK and p25/p35 was assayed in human frontal, hippocampal, cerebellar, cervical (dorsal and ventral) and lumbar (dorsal and ventral) tissue from neurologically intact control (5), ALS (5) or ALSci (5) patients using RT-PCR, Western blot or immunohistochemistry. To assess GSK-3beta activity, we examined GSK3beta, phospho-GSK3beta and phospho-beta-catenin expression. Expression levels relative to that of beta-actin were compared by ANOVA. The expression of GSK, GSK3beta and phospho-GSK3beta was increased in both ALS and ALSci compared to that of the control. This was accompanied by an increased expression of phospho-beta-catenin. No significant difference between control, ALS or ALSci was observed with respect to the expression of CDK5 or p25/p35. Both GSK3beta and phospho-GSK3beta immunoreactive neurons were mainly located in layer II and layer III in the frontal cortex and in layer II in the hippocampus. This was consistent with the previously described distribution of hyperphosphorylated tau bearing neurons in ALS and ALSci. These data suggest that GSK3beta expression is upregulated in ALS and ALSci and that GSK3beta activation is associated with the intraneuronal deposition of hyperphosphorylated tau protein. This supports the potential role for GSK3beta as a therapeutic target in ALS.
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Affiliation(s)
- Wencheng Yang
- Robarts Research Institute, The University of Western Ontario, London, Ontario, Canada
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Petrik MS, Wilson JMB, Grant SC, Blackband SJ, Tabata RC, Shan X, Krieger C, Shaw CA. Magnetic resonance microscopy and immunohistochemistry of the CNS of the mutant SOD murine model of ALS reveals widespread neural deficits. Neuromolecular Med 2007; 9:216-29. [PMID: 17914180 DOI: 10.1007/s12017-007-8002-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 11/30/1999] [Accepted: 12/20/2006] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that primarily affects motor neurons and descending motor tracts of the CNS. We have evaluated the CNS of a murine model of familial ALS based on the over-expression of mutant human superoxide dismutase (mSOD; G93A) using magnetic resonance microscopy (MRM) and immunohistochemistry (IHC). Three-dimensional volumetric analysis was performed from 3D T2*-weighted images acquired at 17.6 T at isotropic resolutions of 40 mum. Compared to controls, mSOD mice had significant reductions in the volumes of total brain, substantia nigra, striatum, hippocampus, and internal capsule, with decreased cortical thickness in primary motor and somatosensory cortices. In the spinal cord, mSOD mice had significantly decreased volume of both the total grey and white matter; in the latter case, the volume change was confined to the dorsal white matter. Increased apoptosis, GFAP positive astrocytes, and/or activated microglia were observed in all those CNS regions that showed volume loss except for the hippocampus. The MRM findings in mSOD over-expressing mice are similar to data previously obtained from a model of ALS-parkinsonism dementia complex (ALS-PDC), in which neural damage occurred following a diet of washed cycad flour containing various neurotoxins. The primary difference between the two models involves a significantly greater decrease in spinal cord white matter volume in mSOD mice, perhaps reflecting variations in degeneration of the descending motor tracts. The extent to which several CNS structures are impacted in both murine models of ALS argues for a reevaluation of the nature of the pathogenesis of ALS since CNS structures involved in Parkinson's and Alzheimer's diseases appear to be affected as well.
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Affiliation(s)
- M S Petrik
- Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada.
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43
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Shaw CA, Höglinger GU. Neurodegenerative diseases: neurotoxins as sufficient etiologic agents? Neuromolecular Med 2007; 10:1-9. [PMID: 17985252 DOI: 10.1007/s12017-007-8016-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2007] [Accepted: 10/09/2007] [Indexed: 11/26/2022]
Abstract
A dominant paradigm in neurological disease research is that the primary etiological factors for diseases such as Alzheimer's (AD), Parkinson's (PD), and amyotrophic lateral sclerosis (ALS) are genetic. Opposed to this perspective are the clear observations from epidemiology that purely genetic casual factors account for a relatively small fraction of all cases. Many who support a genetic etiology for neurological disease take the view that while the percentages may be relatively small, these numbers will rise in the future with the inevitable discoveries of additional genetic mutations. The follow up argument is that even if the last is not true, the events triggered by the aberrant genes identified so far will be shown to impact the same neuronal cell death pathways as those activated by environmental factors that trigger most sporadic disease cases. In this article we present a countervailing view that environmental neurotoxins may be the sole sufficient factor in at least three neurological disease clusters. For each, neurotoxins have been isolated and characterized that, at least in animal models, faithfully reproduce each disorder without the need for genetic co-factors. Based on these data, we will propose a set of principles that would enable any potential toxin to be evaluated as an etiological factor in a given neurodegenerative disease. Finally, we will attempt to put environmental toxins into the context of possible genetically-determined susceptibility.
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Affiliation(s)
- Christopher A Shaw
- Department of Ophthalmology, University of British Columbia, Vancouver, BC, Canada.
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44
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Kesavapany S, Zheng YL, Amin N, Pant HC. Peptides derived from Cdk5 activator p35, specifically inhibit deregulated activity of Cdk5. Biotechnol J 2007; 2:978-87. [PMID: 17526058 DOI: 10.1002/biot.200700057] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Normal Cdk5 activity, conferred mainly by association with its primary activator p35, is critical for normal function of the cell and must be tightly regulated. During neurotoxicity, p35 is cleaved to form p25, which becomes a potent and mislocalized hyperactivator of Cdk5, resulting in a deregulation of Cdk5 activity. p25 levels have been found to be elevated in Alzheimer's disease (AD) brain and overexpression of p25 in a transgenic mouse results in the formation of phosphorylated tau, neurofibrillary tangles and cognitive deficits that are pathological hallmarks of AD. p25/Cdk5 also hyperphosphorylates neurofilament proteins that constitute pathological hallmarks found in Parkinson's disease and amyotrophic lateral sclerosis. The selective targeting of p25/Cdk5 activity without affecting p35/Cdk5 activity has been unsuccessful. In this review we detail our recent studies of selective p25/Cdk5 inhibition without affecting p35/Cdk5 or mitotic Cdk activities. We found that a further truncation of p25 to yield a Cdk5 inhibitory peptide (CIP) can specifically inhibit p25/Cdk5 activity in transfected HEK cells and primary cortical neurons. CIP was able to reduce tau hyperphosphorylation and neuronal death induced caused by p25/Cdk5 and further studies with CIP may develop a specific Cdk5 inhibition strategy in the treatment of neurodegeneration.
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Affiliation(s)
- Sashi Kesavapany
- Yong Loo Lin School of Medicine, Department of Biochemistry, Singapore, Singapore
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45
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Talbot K, Ansorge O. Recent advances in the genetics of amyotrophic lateral sclerosis and frontotemporal dementia: common pathways in neurodegenerative disease. Hum Mol Genet 2006; 15 Spec No 2:R182-7. [PMID: 16987882 DOI: 10.1093/hmg/ddl202] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease classically defined by the impairment of the voluntary motor system and ubiquitin-positive intraneuronal aggregates in anterior horn cells. Frontotemporal dementia (FTD) is a common form of neurodegenerative dementia and presents with personality change associated in a significant subgroup of patients with cortical ubiquitin-only neuropathology (FTD-U). Careful study of ALS as well as FTD patient cohorts suggests clinical as well as pathological overlap of ALS with FTD. The idea that this reflects a shared pathogenesis has received strong support from the identification of new genetic loci on chromosome 9p and of mutations in specific genes (CHMP2B and DCN1) in families with co-segregation of ALS and FTD. The identification of two further genetic causes of FTD-U with (rare) ALS (PGRN) or without ALS (VCP) also provides a starting point for exploring the pathways associated with ubiquitin-mediated protein mishandling in FTD-U and ALS. Pure ALS, through ALS with cognitive impairment and ALS-FTD to pure FTD-U, may represent a continuous spectrum of ubiquitin-associated neurodegenerative disease.
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Affiliation(s)
- Kevin Talbot
- Department of Physiology, Anatomy and Genetics , University of Oxford, Henry Wellcome Building of Gene Function, South Parks Road, Oxford OX1 3QX, UK.
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