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Zahoor M, Farhat SM, Khan S, Ahmed T. Daidzin improves neurobehavioral outcome in rat model of traumatic brain injury. Behav Brain Res 2024; 472:115158. [PMID: 39047874 DOI: 10.1016/j.bbr.2024.115158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 07/13/2024] [Accepted: 07/21/2024] [Indexed: 07/27/2024]
Abstract
Traumatic brain injury (TBI) is associated with the etiology of multiple neurological disorders, including neurodegeneration, leading to various cognitive deficits. Daidzin (obtained from kudzu root and soybean leaves) is known for its neuroprotective effects through multiple mechanisms. This study aimed to investigate the pharmacological effects of Daidzin on sensory, and biochemical parameters, cognitive functions, anxiety, and depressive-like behaviors in the TBI rat model. Rats were divided into four groups (Control, TBI, TBI + Ibuprofen (30 mg/kg), and TBI + Daidzin (5 mg/kg)). Rats were subjected to TBI by dropping a 200 g rod from a height of 26 cm, resulting in an impact force of 0.51 J on the exposed crania. Ibuprofen (30 mg/kg) was used as a positive control reference/standard drug and Daidzin (5 mg/kg) as the test drug. Neurological severity score (NSS) assessment was done to determine the intactness of sensory and motor responses. Brain tissue edema and acetylcholine levels were determined in the cortex and hippocampus. Cognitive functions such as hippocampus-dependent memory, novel object recognition, exploration, depressive and anxiety-like behaviors were measured. Treatment with Daidzin improved NSS, reduced hippocampal and cortical edema, and improved levels of acetylcholine in TBI-induced rats. Furthermore, Daidzin treatment improved hippocampus-dependent memory, exploration behavior, and novel object recognition while reducing depressive and anxiety-like behavior. Our study revealed that Daidzin has a therapeutic potential comparable to Ibuprofen and can offer neuroprotection and enhanced cognitive and behavioral outcomes in rats after TBI.
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Affiliation(s)
- Maryam Zahoor
- Neurobiology Laboratory, Department of Biomedicine, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Sector H-12, Islamabad 44000, Pakistan
| | - Syeda Mehpara Farhat
- Department of Biological Sciences, National University of Medical Sciences, Rawalpindi 46000, Pakistan
| | - Salman Khan
- Department of Pharmacy, Quaid-i-Azam University, Islamabad, Pakistan
| | - Touqeer Ahmed
- Neurobiology Laboratory, Department of Biomedicine, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Sector H-12, Islamabad 44000, Pakistan.
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Collins HM, Greenfield S. Rodent Models of Alzheimer's Disease: Past Misconceptions and Future Prospects. Int J Mol Sci 2024; 25:6222. [PMID: 38892408 PMCID: PMC11172947 DOI: 10.3390/ijms25116222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/28/2024] [Accepted: 06/03/2024] [Indexed: 06/21/2024] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease with no effective treatments, not least due to the lack of authentic animal models. Typically, rodent models recapitulate the effects but not causes of AD, such as cholinergic neuron loss: lesioning of cholinergic neurons mimics the cognitive decline reminiscent of AD but not its neuropathology. Alternative models rely on the overexpression of genes associated with familial AD, such as amyloid precursor protein, or have genetically amplified expression of mutant tau. Yet transgenic rodent models poorly replicate the neuropathogenesis and protein overexpression patterns of sporadic AD. Seeding rodents with amyloid or tau facilitates the formation of these pathologies but cannot account for their initial accumulation. Intracerebral infusion of proinflammatory agents offer an alternative model, but these fail to replicate the cause of AD. A novel model is therefore needed, perhaps similar to those used for Parkinson's disease, namely adult wildtype rodents with neuron-specific (dopaminergic) lesions within the same vulnerable brainstem nuclei, 'the isodendritic core', which are the first to degenerate in AD. Site-selective targeting of these nuclei in adult rodents may recapitulate the initial neurodegenerative processes in AD to faithfully mimic its pathogenesis and progression, ultimately leading to presymptomatic biomarkers and preventative therapies.
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Affiliation(s)
- Helen M. Collins
- Neuro-Bio Ltd., Building F5 The Culham Campus, Abingdon OX14 3DB, UK;
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Sahara N, Yanai R. Limitations of human tau-expressing mouse models and novel approaches of mouse modeling for tauopathy. Front Neurosci 2023; 17:1149761. [PMID: 37152607 PMCID: PMC10157230 DOI: 10.3389/fnins.2023.1149761] [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: 01/23/2023] [Accepted: 03/24/2023] [Indexed: 05/09/2023] Open
Abstract
Neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau protein are primarily neuropathological features of a number of neurodegenerative diseases, collectively termed tauopathy. There is no disease-modifying drug available for tauopathy except anti-amyloid antibody therapies for Alzheimer's disease. For tau-targeting therapy, experimental models recapitulating human tau pathologies are indispensable. However, there are limited numbers of animal models that display intracellular filamentous tau aggregations. At present, several lines of P301L/S mutant tau-expressing transgenic mice successfully developed neurofibrillary pathology in the central nervous system, while most non-mutant tau-expressing transgenic mice rarely developed tau pathology. Importantly, recent studies have revealed that transgenes disrupt the coding sequence of endogenous genes, resulting in deletions and/or structural variations at the insertion site. Although any impact on the pathogenesis of tauopathy is unknown, gene disruptions may affect age-related neurodegeneration including tangle formation and brain atrophy. Moreover, some mouse lines show strain-dependent pathological features. These limitations (FTDP-17 mutations, insertion/deletion mutations, and genetic background) are a major hindrance to the establishment of a precise disease model of tauopathy. In this review, we noticed both the utility and the pitfalls of current P301L/S mutant tau-expressing transgenic mice, and we propose future strategies of mouse modeling to replicate human tauopathies.
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Affiliation(s)
- Naruhiko Sahara
- Department of Functional Brain Imaging, Institute for Quantum Medical Sciences, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Rin Yanai
- Department of Functional Brain Imaging, Institute for Quantum Medical Sciences, National Institutes for Quantum Science and Technology, Chiba, Japan
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Yang Y, Tapias V, Acosta D, Xu H, Chen H, Bhawal R, Anderson ET, Ivanova E, Lin H, Sagdullaev BT, Chen J, Klein WL, Viola KL, Gandy S, Haroutunian V, Beal MF, Eliezer D, Zhang S, Gibson GE. Altered succinylation of mitochondrial proteins, APP and tau in Alzheimer's disease. Nat Commun 2022; 13:159. [PMID: 35013160 PMCID: PMC8748865 DOI: 10.1038/s41467-021-27572-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 11/25/2021] [Indexed: 02/07/2023] Open
Abstract
Abnormalities in brain glucose metabolism and accumulation of abnormal protein deposits called plaques and tangles are neuropathological hallmarks of Alzheimer's disease (AD), but their relationship to disease pathogenesis and to each other remains unclear. Here we show that succinylation, a metabolism-associated post-translational protein modification (PTM), provides a potential link between abnormal metabolism and AD pathology. We quantified the lysine succinylomes and proteomes from brains of individuals with AD, and healthy controls. In AD, succinylation of multiple mitochondrial proteins declined, and succinylation of small number of cytosolic proteins increased. The largest increases occurred at critical sites of amyloid precursor protein (APP) and microtubule-associated tau. We show that in vitro, succinylation of APP disrupted its normal proteolytic processing thereby promoting Aβ accumulation and plaque formation and that succinylation of tau promoted its aggregation to tangles and impaired microtubule assembly. In transgenic mouse models of AD, elevated succinylation associated with soluble and insoluble APP derivatives and tau. These findings indicate that a metabolism-linked PTM may be associated with AD.
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Affiliation(s)
- Yun Yang
- Integrated Medicine Research Center for Neurological Rehabilitation, College of Medicine, Jiaxing University, 314001, Jiaxing, China
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
- Burke Neurological Institute, White Plains, NY, 10605, USA
| | - Victor Tapias
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Diana Acosta
- Department of Biochemistry, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Hui Xu
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
- Burke Neurological Institute, White Plains, NY, 10605, USA
| | - Huanlian Chen
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
- Burke Neurological Institute, White Plains, NY, 10605, USA
| | - Ruchika Bhawal
- Proteomics and Metabolomics Facility, Institute of Biotechnology, Cornell University, Ithaca, NY, 14853, USA
| | - Elizabeth T Anderson
- Proteomics and Metabolomics Facility, Institute of Biotechnology, Cornell University, Ithaca, NY, 14853, USA
| | - Elena Ivanova
- Imaging Core, Burke Neurological Institute, White Plains, NY, 10605, USA
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY, 10591, USA
| | - Hening Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Botir T Sagdullaev
- Ophthalmology and Neuroscience, Weill Cornell Medicine, New York, NY, 10065, USA
- Laboratory for Visual Plasticity and Repair, Burke Neurological Institute, White Plains, NY, 10605, USA
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY, 10591, USA
| | - Jianer Chen
- Integrated Medicine Research Center for Neurological Rehabilitation, College of Medicine, Jiaxing University, 314001, Jiaxing, China
| | - William L Klein
- Department of Neurobiology, Northwestern University, Evanston, IL, 60208, USA
| | - Kirsten L Viola
- Department of Neurobiology, Northwestern University, Evanston, IL, 60208, USA
| | - Sam Gandy
- Department of Neurology and Mount Sinai Center for Cognitive Health and NFL Neurological Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Research and Development Service and Division of Neurology, James J Peters VA Medical Center, 130 West Kingsbridge Rd, Bronx, NY, 10468, USA
- James J Peters Veterans Medical Center, Bronx, NY, 10468, USA
- Department of Psychiatry Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Vahram Haroutunian
- Department of Psychiatry Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- JJ Peters VA Medical Center MIRECC, Bronx, NY, 10468, USA
- Mount Sinai NIH Neurobiobank, New York, NY, 10029, USA
| | - M Flint Beal
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Sheng Zhang
- Proteomics and Metabolomics Facility, Institute of Biotechnology, Cornell University, Ithaca, NY, 14853, USA
| | - Gary E Gibson
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA.
- Burke Neurological Institute, White Plains, NY, 10605, USA.
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Therapeutic Ultrasound as a Treatment Modality for Physiological and Pathological Ageing Including Alzheimer's Disease. Pharmaceutics 2021; 13:pharmaceutics13071002. [PMID: 34371696 PMCID: PMC8309087 DOI: 10.3390/pharmaceutics13071002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 01/09/2023] Open
Abstract
Physiological and pathological ageing (as exemplified by Alzheimer's disease, AD) are characterized by a progressive decline that also includes cognition. How this decline can be slowed or even reversed is a critical question. Here, we discuss therapeutic ultrasound as a novel modality to achieve this goal. In our studies, we explored three fundamental strategies, (i) scanning ultrasound on its own (SUSonly), (ii) therapeutic ultrasound in concert with intravenously injected microbubbles (which transiently opens the blood-brain barrier, SUS+MB), and (iii) SUS+MB in combination with therapeutic antibodies (SUS+MB+mAb). These studies show SUS+MB effectively clears amyloid and restores memory in amyloid-depositing mice and partially clears Tau and ameliorates memory impairments in Tau transgenic mice, with additional improvements found in combination trials (SUS+MB+mAb). Interestingly, both SUSonly and SUS+MB restored the induction of long-term potentiation (LTP, electrophysiological correlate of memory) in senescent wild-type mice. Both lead to increased neurogenesis, and SUSonly, in particular, resulted in improved spatial memory. We discuss these findings side-by-side with our findings obtained in AD mouse models. We conclude that therapeutic ultrasound is a non-invasive, pleiotropic modality that may present a treatment option not only for AD but also for enhancing cognition in physiological ageing.
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SWI and phase imaging reveal intracranial calcifications in the P301L mouse model of human tauopathy. MAGMA (NEW YORK, N.Y.) 2020; 33:769-781. [PMID: 32468149 PMCID: PMC7669813 DOI: 10.1007/s10334-020-00855-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/12/2020] [Accepted: 05/19/2020] [Indexed: 12/14/2022]
Abstract
Objective Brain calcifications are associated with several neurodegenerative diseases. Here, we describe the occurrence of intracranial calcifications as a new phenotype in transgenic P301L mice overexpressing four repeat tau, a model of human tauopathy. Materials and methods Thirty-six P301L mice (Thy1.2) and ten age-matched non-transgenic littermates of different ages were assessed. Gradient echo data were acquired in vivo and ex vivo at 7 T and 9.4 T for susceptibility-weighted imaging (SWI) and phase imaging. In addition, ex vivo micro-computed tomography (μCT) was performed. Histochemistry and immunohistochemistry were used to investigate the nature of the imaging lesions. Results SW images revealed regional hypointensities in the hippocampus, cortex, caudate nucleus, and thalamus of P301L mice, which in corresponding phase images indicated diamagnetic lesions. Concomitantly, µCT detected hyperdense lesions, though fewer lesions were observed compared to MRI. Diamagnetic susceptibility lesions in the hippocampus increased with age. The immunochemical staining of brain sections revealed osteocalcin-positive deposits. Furthermore, intra-neuronal and vessel-associated osteocalcin-containing nodules co-localized with phosphorylated-tau (AT8 and AT100) in the hippocampus, while vascular osteocalcin-containing nodules were detected in the thalamus in the absence of phosphorylated-tau deposition. Discussion SWI and phase imaging sensitively detected intracranial calcifications in the P301L mouse model of human tauopathy. Electronic supplementary material The online version of this article (10.1007/s10334-020-00855-3) contains supplementary material, which is available to authorized users.
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Craven KM, Kochen WR, Hernandez CM, Flinn JM. Zinc Exacerbates Tau Pathology in a Tau Mouse Model. J Alzheimers Dis 2019; 64:617-630. [PMID: 29914030 DOI: 10.3233/jad-180151] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Hyperphosphorylated tau protein is a key pathology in Alzheimer's disease (AD), frontotemporal dementia, chronic traumatic encephalopathy, and Parkinson's disease. The essential trace element zinc exacerbates tauopathy in vitro as well as in a Drosophila model of AD. However, the interaction has never been assessed behaviorally or biochemically in mammals. Zinc supplementation is prevalent in society, finding use as a treatment for macular degeneration and cataracts, and is also taken as an immune system booster with high levels appearing in multivitamins marketed toward the elderly. Using a transgenic mouse model that contains the human gene for tau protein (P301L), we assessed the effects of excess chronic zinc supplementation on tau pathology. Behavioral tests included nest building, circadian rhythm, Morris Water Maze, fear conditioning, and open field. Biochemically, total tau and Ser396 phosphorylation were assessed using western blot. Number of tangles were assessed by Thioflavin-S and free zinc levels were assessed by Zinpyr-1. Tau mice demonstrated behavioral deficits compared to control mice. Zinc supplementation exacerbated tauopathic deficits in circadian rhythm, nesting behavior, and Morris Water Maze. Biochemically, zinc-supplemented tau mice showed increased phosphorylation at pSer396. Zinc supplementation in tau mice also increased tangle numbers in the hippocampus while decreasing free-zinc levels, demonstrating that tangles were sequestering zinc. These results show that zinc intensified the deficits in behavior and biochemistry caused by tau.
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8
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The ProNGF/p75NTR pathway induces tau pathology and is a therapeutic target for FTLD-tau. Mol Psychiatry 2018; 23:1813-1824. [PMID: 29867188 DOI: 10.1038/s41380-018-0071-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 01/26/2018] [Accepted: 03/26/2018] [Indexed: 11/09/2022]
Abstract
Tau pathology is characterized as a form of frontotemporal lobar degeneration (FTLD) known as FTLD-tau. The underlying pathogenic mechanisms are not known and no therapeutic interventions are currently available. Here, we report that the neurotrophin receptor p75NTR plays a critical role in the pathogenesis of FTLD-tau. The expression of p75NTR and the precursor of nerve growth factor (proNGF) were increased in the brains of FTLD-tau patients and mice (P301L transgenic). ProNGF-induced tau phosphorylation via p75NTR in vitro, which was associated with the AKT/glycogen synthase kinase (GSK)3β pathway. Genetic reduction of p75NTR in P301L mice rescued the memory deficits, alleviated tau hyperphosphorylation and restored the activity of the AKT/GSK3β pathway. Treatment of the P301L mice with the soluble p75NTR extracellular domain (p75ECD-Fc), which can antagonize neurotoxic ligands of p75NTR, effectively improved memory behavior and suppressed tau pathology. This suggests that p75NTR plays a crucial role in tau paGSKthology and represents a potential druggable target for FTLD-tau and related tauopathies.
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Köhler C, Fuhr V, Dinekov M. Distribution of spleen tyrosine kinase and tau phosphorylated at tyrosine 18 in a mouse model of tauopathy and in the human hippocampus. Brain Res 2017; 1677:1-13. [DOI: 10.1016/j.brainres.2017.08.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 08/11/2017] [Accepted: 08/25/2017] [Indexed: 12/01/2022]
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Nisbet RM, Van der Jeugd A, Leinenga G, Evans HT, Janowicz PW, Götz J. Combined effects of scanning ultrasound and a tau-specific single chain antibody in a tau transgenic mouse model. Brain 2017; 140:1220-1230. [PMID: 28379300 PMCID: PMC5405237 DOI: 10.1093/brain/awx052] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 01/26/2017] [Indexed: 12/30/2022] Open
Abstract
Alzheimer’s disease is characterized by the deposition of amyloid-β as extracellular plaques and hyperphosphorylated tau as intracellular neurofibrillary tangles. Tau pathology characterizes not only Alzheimer’s disease, but also many other tauopathies, presenting tau as an attractive therapeutic target. Passive tau immunotherapy has been previously explored; however, because only a small fraction of peripherally delivered antibodies crosses the blood–brain barrier, enters the brain and engages with tau that forms intracellular aggregates, more efficient ways of antibody delivery and neuronal uptake are warranted. In the brain, tau exists as multiple isoforms. Here, we investigated the efficacy of a novel 2N tau isoform-specific single chain antibody fragment, RN2N, delivered by passive immunization in the P301L human tau transgenic pR5 mouse model. We demonstrate that, in treated mice, RN2N reduces anxiety-like behaviour and phosphorylation of tau at distinct sites. When administration of RN2N was combined with focused ultrasound in a scanning mode (scanning ultrasound), RN2N delivery into the brain and uptake by neurons were markedly increased, and efficacy was significantly enhanced. Our study provides evidence that scanning ultrasound is a viable tool to enhance the delivery of biologics across the blood–brain barrier and improve therapeutic outcomes and further presents single-chain antibodies as an alternative to full-length antibodies.
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Affiliation(s)
- Rebecca M Nisbet
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Ann Van der Jeugd
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Gerhard Leinenga
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Harrison T Evans
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Phillip W Janowicz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
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Bodea L, Evans HT, Van der Jeugd A, Ittner LM, Delerue F, Kril J, Halliday G, Hodges J, Kiernan MC, Götz J. Accelerated aging exacerbates a pre-existing pathology in a tau transgenic mouse model. Aging Cell 2017; 16:377-386. [PMID: 28160413 PMCID: PMC5334525 DOI: 10.1111/acel.12565] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2016] [Indexed: 12/31/2022] Open
Abstract
Age is a critical factor in the prevalence of tauopathies, including Alzheimer's disease. To observe how an aging phenotype interacts with and affects the pathological intracellular accumulation of hyperphosphorylated tau, the tauopathy mouse model pR5 (expressing P301L mutant human tau) was back‐crossed more than ten times onto a senescence‐accelerated SAMP8 background to establish the new strain, SApT. Unlike SAMP8 mice, pR5 mice are characterized by a robust tau pathology particularly in the amygdala and hippocampus. Analysis of age‐matched SApT mice revealed that pathological tau phosphorylation was increased in these brain regions compared to those in the parental pR5 strain. Moreover, as revealed by immunohistochemistry, phosphorylation of critical tau phospho‐epitopes (P‐Ser202/P‐Ser205 and P‐Ser235) was significantly increased in the amygdala of SApT mice in an age‐dependent manner, suggesting an age‐associated effect of tau phosphorylation. Anxiety tests revealed that the older cohort of SApT mice (10 months vs. 8 months) exhibited a behavioural pattern similar to that observed for age‐matched tau transgenic pR5 mice and not the SAMP8 parental mice. Learning and memory, however, appeared to be governed by the accelerated aging background of the SAMP8 strain, as at both ages investigated, SAMP8 and SApT mice showed a decreased learning capacity compared to pR5 mice. We therefore conclude that accelerated aging exacerbates pathological tau phosphorylation, leading to changes in normal behaviour. These findings further suggest that SApT mice may be a useful novel model in which to study the role of a complex geriatric phenotype in tauopathy.
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Affiliation(s)
- Liviu‐Gabriel Bodea
- Clem Jones Centre for Ageing Dementia Research (CJCADR) Queensland Brain Institute (QBI) The University of Queensland Brisbane Qld Australia
| | - Harrison Tudor Evans
- Clem Jones Centre for Ageing Dementia Research (CJCADR) Queensland Brain Institute (QBI) The University of Queensland Brisbane Qld Australia
| | - Ann Van der Jeugd
- Clem Jones Centre for Ageing Dementia Research (CJCADR) Queensland Brain Institute (QBI) The University of Queensland Brisbane Qld Australia
| | - Lars M. Ittner
- University of New South Wales and Neuroscience Research Australia Sydney NSW Australia
| | - Fabien Delerue
- University of New South Wales and Neuroscience Research Australia Sydney NSW Australia
| | - Jillian Kril
- Discipline of Pathology Sydney Medical School University of Sydney Sydney NSW Australia
| | - Glenda Halliday
- University of New South Wales and Neuroscience Research Australia Sydney NSW Australia
| | - John Hodges
- University of New South Wales and Neuroscience Research Australia Sydney NSW Australia
| | | | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research (CJCADR) Queensland Brain Institute (QBI) The University of Queensland Brisbane Qld Australia
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Mouse models of frontotemporal dementia: A comparison of phenotypes with clinical symptomatology. Neurosci Biobehav Rev 2017; 74:126-138. [DOI: 10.1016/j.neubiorev.2017.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 01/04/2017] [Accepted: 01/06/2017] [Indexed: 12/12/2022]
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Klingebiel M, Dinekov M, Köhler C. Analysis of ribosomal protein S6 baseline phosphorylation and effect of tau pathology in the murine brain and human hippocampus. Brain Res 2017; 1659:121-135. [PMID: 28119058 DOI: 10.1016/j.brainres.2017.01.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 01/17/2023]
Abstract
We examined the distribution pattern of the phosphorylated 40S ribosomal subunit protein S6, a downstream target of the mTOR pathway, in the brains of 24-months-old human tau transgenic pR5 mice, non-transgenic littermates and in human hippocampi. We studied baseline levels of phosphorylated S6 and a possible effect of tau pathology. S6 phosphorylated at Ser235/236 (pS6Ser235/236) or Ser240/244 (pS6Ser240/244) has been used as a read-out of mTOR activity in several studies. The mTOR pathway regulates a wide variety of cellular functions including cell growth, ribosome biosynthesis, translational control and autophagy. Its dysregulation might underlie the neurodegenerative pathology of Alzheimer's disease and other tauopathies. pS6Ser235/236 and pS6Ser240/244 immunoreactivity in the mouse brain were widespread and similar distributed, but intensive pS6Ser235/236 immunoreactivity was more selective, especially highlighting certain brainstem regions. In the human hippocampus mainly granulovacuolar inclusions in neurons displayed pS6Ser235/236 immunoreactivity. In contrast, a considerable number of neurons displayed pS6Ser240/244 immunoreactivity in the cytoplasm without labeling of granulovacuolar inclusions. Except for a tendency of lower numbers of intensely phosphorylated S6-positive neurons in pR5 mice, the pattern of distribution of pS6Ser235/236 and pS6Ser240/244 immunoreactivity was largely unchanged when compared with non-transgenic mice and also when human hippocampi from AD cases and controls were compared. Similar to pR5 mice most neurons with hyper-phosphorylated tau in human hippocampi displayed no or only weak labeling for phosphorylated S6, suggesting that phosphorylated S6 is not especially associated with pathological tau, but is rather a feature of unaffected neurons.
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Affiliation(s)
- Maria Klingebiel
- Institute II for Anatomy, Medical Faculty, University of Cologne, Kerpener Str. 62, 50924 Cologne, Germany
| | - Maja Dinekov
- Institute II for Anatomy, Medical Faculty, University of Cologne, Kerpener Str. 62, 50924 Cologne, Germany
| | - Christoph Köhler
- Institute II for Anatomy, Medical Faculty, University of Cologne, Kerpener Str. 62, 50924 Cologne, Germany.
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Du LY, Chang LYL, Ardiles AO, Tapia-Rojas C, Araya J, Inestrosa NC, Palacios AG, Acosta ML. Alzheimer's Disease-Related Protein Expression in the Retina of Octodon degus. PLoS One 2015; 10:e0135499. [PMID: 26267479 PMCID: PMC4534194 DOI: 10.1371/journal.pone.0135499] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 07/22/2015] [Indexed: 01/06/2023] Open
Abstract
New studies show that the retina also undergoes pathological changes during the development of Alzheimer's disease (AD). While transgenic mouse models used in these previous studies have offered insight into this phenomenon, they do not model human sporadic AD, which is the most common form. Recently, the Octodon degus has been established as a sporadic model of AD. Degus display age-related cognitive impairment associated with Aβ aggregates and phosphorylated tau in the brain. Our aim for this study was to examine the expression of AD-related proteins in young, adult and old degus retina using enzyme-linked or fluorescence immunohistochemistry and to quantify the expression using slot blot and western blot assays. Aβ4G8 and Aβ6E10 detected Aβ peptides in some of the young animals but the expression was higher in the adults. Aβ peptides were observed in the inner and outer segment of the photoreceptors, the nerve fiber layer (NFL) and ganglion cell layer (GCL). Expression was higher in the central retinal region than in the retinal periphery. Using an anti-oligomer antibody we detected Aβ oligomer expression in the young, adult and old retina. Immunohistochemical labeling showed small discrete labeling of oligomers in the GCL that did not resemble plaques. Congo red staining did not result in green birefringence in any of the animals analyzed except for one old (84 months) animal. We also investigated expression of tau and phosphorylated tau. Expression was seen at all ages studied and in adults it was more consistently observed in the NFL-GCL. Hyperphosphorylated tau detected with AT8 antibody was significantly higher in the adult retina and it was localized to the GCL. We confirm for the first time that Aβ peptides and phosphorylated tau are expressed in the retina of degus. This is consistent with the proposal that AD biomarkers are present in the eye.
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Affiliation(s)
- Lucia Y. Du
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Lily Y-L. Chang
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Alvaro O. Ardiles
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| | - Cheril Tapia-Rojas
- Center for Aging and Regeneration (CARE), Department of Cell and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Joaquin Araya
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| | - Nibaldo C. Inestrosa
- Center for Aging and Regeneration (CARE), Department of Cell and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Adrian G. Palacios
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| | - Monica L. Acosta
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
- New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand
- * E-mail:
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15
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Melis V, Zabke C, Stamer K, Magbagbeolu M, Schwab K, Marschall P, Veh RW, Bachmann S, Deiana S, Moreau PH, Davidson K, Harrington KA, Rickard JE, Horsley D, Garman R, Mazurkiewicz M, Niewiadomska G, Wischik CM, Harrington CR, Riedel G, Theuring F. Different pathways of molecular pathophysiology underlie cognitive and motor tauopathy phenotypes in transgenic models for Alzheimer's disease and frontotemporal lobar degeneration. Cell Mol Life Sci 2015; 72:2199-222. [PMID: 25523019 PMCID: PMC4427622 DOI: 10.1007/s00018-014-1804-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 11/22/2014] [Accepted: 12/08/2014] [Indexed: 11/04/2022]
Abstract
A poorly understood feature of the tauopathies is their very different clinical presentations. The frontotemporal lobar degeneration (FTLD) spectrum is dominated by motor and emotional/psychiatric abnormalities, whereas cognitive and memory deficits are prominent in the early stages of Alzheimer's disease (AD). We report two novel mouse models overexpressing different human tau protein constructs. One is a full-length tau carrying a double mutation [P301S/G335D; line 66 (L66)] and the second is a truncated 3-repeat tau fragment which constitutes the bulk of the PHF core in AD corresponding to residues 296-390 fused with a signal sequence targeting it to the endoplasmic reticulum membrane (line 1; L1). L66 has abundant tau pathology widely distributed throughout the brain, with particularly high counts of affected neurons in hippocampus and entorhinal cortex. The pathology is neuroanatomically static and declines with age. Behaviourally, the model is devoid of a higher cognitive phenotype but presents with sensorimotor impairments and motor learning phenotypes. L1 displays a much weaker histopathological phenotype, but shows evidence of neuroanatomical spread and amplification with age that resembles the Braak staging of AD. Behaviourally, the model has minimal motor deficits but shows severe cognitive impairments affecting particularly the rodent equivalent of episodic memory which progresses with advancing age. In both models, tau aggregation can be dissociated from abnormal phosphorylation. The two models make possible the demonstration of two distinct but nevertheless convergent pathways of tau molecular pathogenesis. L1 appears to be useful for modelling the cognitive impairment of AD, whereas L66 appears to be more useful for modelling the motor features of the FTLD spectrum. Differences in clinical presentation of AD-like and FTLD syndromes are therefore likely to be inherent to the respective underlying tauopathy, and are not dependent on presence or absence of concomitant APP pathology.
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Affiliation(s)
- V. Melis
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - C. Zabke
- CCR/Institut für Pharmakologie, Charité-Universitätsmedizin Berlin, Institute of Pharmacology, Hessische Str. 3-4, 10115 Berlin, Germany
| | - K. Stamer
- CCR/Institut für Pharmakologie, Charité-Universitätsmedizin Berlin, Institute of Pharmacology, Hessische Str. 3-4, 10115 Berlin, Germany
| | - M. Magbagbeolu
- CCR/Institut für Pharmakologie, Charité-Universitätsmedizin Berlin, Institute of Pharmacology, Hessische Str. 3-4, 10115 Berlin, Germany
| | - K. Schwab
- CCR/Institut für Pharmakologie, Charité-Universitätsmedizin Berlin, Institute of Pharmacology, Hessische Str. 3-4, 10115 Berlin, Germany
| | - P. Marschall
- CCR/Institut für Pharmakologie, Charité-Universitätsmedizin Berlin, Institute of Pharmacology, Hessische Str. 3-4, 10115 Berlin, Germany
| | - R. W. Veh
- Charité-Universitätsmedizin Berlin, Institute of Anatomy, Berlin, Germany
| | - S. Bachmann
- Charité-Universitätsmedizin Berlin, Institute of Anatomy, Berlin, Germany
| | - S. Deiana
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - P.-H. Moreau
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - K. Davidson
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - K. A. Harrington
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - J. E. Rickard
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - D. Horsley
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - R. Garman
- Consultants in Veterinary Pathology Inc., Murrysville, PA USA
| | | | | | - C. M. Wischik
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - C. R. Harrington
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, Scotland, UK
| | - G. Riedel
- School of Medical Sciences, University of Aberdeen, Foresterhill, AB25 2ZD Scotland, UK
| | - F. Theuring
- CCR/Institut für Pharmakologie, Charité-Universitätsmedizin Berlin, Institute of Pharmacology, Hessische Str. 3-4, 10115 Berlin, Germany
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16
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van Eersel J, Stevens CH, Przybyla M, Gladbach A, Stefanoska K, Chan CKX, Ong WY, Hodges JR, Sutherland GT, Kril JJ, Abramowski D, Staufenbiel M, Halliday GM, Ittner LM. Early-onset axonal pathology in a novel P301S-Tau transgenic mouse model of frontotemporal lobar degeneration. Neuropathol Appl Neurobiol 2015; 41:906-25. [DOI: 10.1111/nan.12233] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 02/23/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Janet van Eersel
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Claire H. Stevens
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Magdalena Przybyla
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Amadeus Gladbach
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Kristie Stefanoska
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Chesed Kai-Xin Chan
- Department of Anatomy; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - Wei-Yi Ong
- Department of Anatomy; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - John R. Hodges
- Neuroscience Research Australia; Sydney Australia
- Faculty of Medicine; University of New South Wales; Sydney Australia
| | | | - Jillian J. Kril
- Discipline of Pathology; University of Sydney; Sydney Australia
| | | | | | - Glenda M. Halliday
- Neuroscience Research Australia; Sydney Australia
- Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Lars M. Ittner
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
- Neuroscience Research Australia; Sydney Australia
- Sydney Medical School; University of Sydney; Sydney Australia
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17
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Dujardin S, Colin M, Buée L. Invited review: Animal models of tauopathies and their implications for research/translation into the clinic. Neuropathol Appl Neurobiol 2015; 41:59-80. [DOI: 10.1111/nan.12200] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 11/23/2014] [Indexed: 02/01/2023]
Affiliation(s)
- Simon Dujardin
- Inserm, UMR1172 Jean-Pierre Aubert Research Centre; Lille France
- Faculté de Médecine; Université de Lille; France
- Memory Clinic; CHRU; Lille France
| | - Morvane Colin
- Inserm, UMR1172 Jean-Pierre Aubert Research Centre; Lille France
- Faculté de Médecine; Université de Lille; France
- Memory Clinic; CHRU; Lille France
| | - Luc Buée
- Inserm, UMR1172 Jean-Pierre Aubert Research Centre; Lille France
- Faculté de Médecine; Université de Lille; France
- Memory Clinic; CHRU; Lille France
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18
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Tian H, Davidowitz E, Lopez P, He P, Schulz P, Moe J, Sierks MR. Isolation and characterization of antibody fragments selective for toxic oligomeric tau. Neurobiol Aging 2014; 36:1342-55. [PMID: 25616912 DOI: 10.1016/j.neurobiolaging.2014.12.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 11/27/2014] [Accepted: 12/04/2014] [Indexed: 11/20/2022]
Abstract
Oligomeric tau species are important in the onset and progression of Alzheimer's disease (AD), as they are neurotoxic and can propagate tau-tangle pathology. Therefore, reagents that selectively recognize different key morphologies of tau are needed to help define the role of tau in AD and related diseases. We utilized a biopanning protocol that combines the binding diversity of phage-displayed antibody libraries with the powerful imaging capability of atomic force microscopy to isolate single-chain antibody fragments (scFvs) that selectively bind toxic oligomeric tau. We isolated 3 different antibody fragments that bind oligomeric but not monomeric or fibrillar tau. The scFvs differentiate brain tissue homogenates of both 3×TG and tau-AD mice from wild-type mice, detecting oligomeric tau at much earlier ages than when neurofibrillary tangles are typically detected. The scFvs also distinguish human postmortem AD brain tissue from cognitively normal postmortem human brain tissue, demonstrating the potential of this approach for developing biomarkers for early detection and progression of AD.
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Affiliation(s)
- Huilai Tian
- Department of Chemical Engineering, Arizona State University, Tempe, AZ, USA
| | | | | | - Ping He
- Department of Chemical Engineering, Arizona State University, Tempe, AZ, USA
| | - Philip Schulz
- Department of Chemical Engineering, Arizona State University, Tempe, AZ, USA
| | | | - Michael R Sierks
- Department of Chemical Engineering, Arizona State University, Tempe, AZ, USA.
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19
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Granulovacuolar degeneration and unfolded protein response in mouse models of tauopathy and Aβ amyloidosis. Neurobiol Dis 2014; 71:169-79. [DOI: 10.1016/j.nbd.2014.07.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 07/04/2014] [Accepted: 07/17/2014] [Indexed: 01/09/2023] Open
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20
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Eckert A, Nisbet R, Grimm A, Götz J. March separate, strike together--role of phosphorylated TAU in mitochondrial dysfunction in Alzheimer's disease. Biochim Biophys Acta Mol Basis Dis 2013; 1842:1258-66. [PMID: 24051203 DOI: 10.1016/j.bbadis.2013.08.013] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 08/08/2013] [Accepted: 08/12/2013] [Indexed: 12/17/2022]
Abstract
The energy demand and calcium buffering requirements of the brain are met by the high number of mitochondria in neurons and in these, especially at the synapses. Mitochondria are the major producer of reactive oxygen species (ROS); at the same time, they are damaged by ROS that are induced by abnormal protein aggregates that characterize human neurodegenerative diseases such as Alzheimer's disease (AD). Because synaptic mitochondria are long-lived, any damage exerted by these aggregates impacts severely on neuronal function. Here we review how increased TAU, a defining feature of AD and related tauopathies, impairs mitochondrial function by following the principle: 'March separate, strike together!' In the presence of amyloid-β, TAU's toxicity is augmented suggesting synergistic pathomechanisms. In order to restore mitochondrial functions in neurodegeneration as a means of therapeutic intervention it will be important to integrate the various aspects of dysfunction and get a handle on targeting distinct cell types and subcellular compartments.
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Affiliation(s)
- Anne Eckert
- Neurobiology Laboratory, Psychiatric University Clinics Basel, University of Basel, Switzerland
| | - Rebecca Nisbet
- Centre for Ageing Dementia Research (CADR), Queensland Brain Institute (QBI), The University of Queensland, Australia
| | - Amandine Grimm
- Neurobiology Laboratory, Psychiatric University Clinics Basel, University of Basel, Switzerland
| | - Jürgen Götz
- Centre for Ageing Dementia Research (CADR), Queensland Brain Institute (QBI), The University of Queensland, Australia.
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21
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Yoshiyama Y, Lee VMY, Trojanowski JQ. Therapeutic strategies for tau mediated neurodegeneration. J Neurol Neurosurg Psychiatry 2013; 84:784-95. [PMID: 23085937 PMCID: PMC3912572 DOI: 10.1136/jnnp-2012-303144] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Based on the amyloid hypothesis, controlling β-amyloid protein (Aβ) accumulation is supposed to suppress downstream pathological events, tau accumulation, neurodegeneration and cognitive decline. However, in recent clinical trials, Aβ removal or reducing Aβ production has shown limited efficacy. Moreover, while active immunisation with Aβ resulted in the clearance of Aβ, it did not prevent tau pathology or neurodegeneration. This prompts the concern that it might be too late to employ Aβ targeting therapies once tau mediated neurodegeneration has occurred. Therefore, it is timely and very important to develop tau directed therapies. The pathomechanisms of tau mediated neurodegeneration are unclear but hyperphosphorylation, oligomerisation, fibrillisation and propagation of tau pathology have been proposed as the likely pathological processes that induce loss of function or gain of toxic function of tau, causing neurodegeneration. Here we review the strategies for tau directed treatments based on recent progress in research on tau and our understanding of the pathomechanisms of tau mediated neurodegeneration.
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Affiliation(s)
- Yasumasa Yoshiyama
- Department of Neurology, Chiba East National Hospital, 673 Nitona, Chuo Ward, Chiba, Chiba 260-8712, Japan.
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22
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Yan L, Li L, Han W, Pan B, Xue X, Mei B. Age-related neuropsychiatric symptoms in presenilins conditional double knockout mice. Brain Res Bull 2013; 97:104-11. [PMID: 23792007 DOI: 10.1016/j.brainresbull.2013.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 06/02/2013] [Accepted: 06/05/2013] [Indexed: 11/28/2022]
Abstract
Alzheimer's disease (AD) is the most common form of dementia and causes impairments of memory, cognition and behavior. Remarkably, most AD patients exhibit personality changes that often precede other early clinical manifestations. Conditional presenilin1 (PS1) and presenilin2 (PS2) double knockout (DKO) mice have age-related forebrain atrophy, tau hyperphosphorylation, synaptic dysfunction, cognitive deficits and increased inflammatory responses in both the periphery and the brain. Whether these mice have age-related emotional changes have not yet been investigated. In the present study, we used 2-, 6- and 11-month-old DKO and littermate control (CON) mice to examine their age-related emotional conditions. Our results indicate that DKO mice have observable age-related neuropsychiatric symptoms, such as anxiety, irritability, depression, apathy, aggressivity, anhedonia and aberrant motor behavior when compared with other AD-like mouse models. In summary, our results not only indicate that DKO mice may be a valuable model for probing age-related AD diagnoses but also suggest a new pathogenesis of neurodegenerative diseases that is worth further investigation.
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Affiliation(s)
- Li Yan
- Shanghai Key Laboratory of Brain Functional Genomics, Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, Shanghai 200062, China
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23
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Götz J, Xia D, Leinenga G, Chew YL, Nicholas HR. What Renders TAU Toxic. Front Neurol 2013; 4:72. [PMID: 23772223 PMCID: PMC3677143 DOI: 10.3389/fneur.2013.00072] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 05/28/2013] [Indexed: 12/21/2022] Open
Abstract
TAU is a microtubule-associated protein that under pathological conditions such as Alzheimer's disease (AD) forms insoluble, filamentous aggregates. When 20 years after TAU's discovery the first TAU transgenic mouse models were established, one declared goal that was achieved was the modeling of authentic TAU aggregate formation in the form of neurofibrillary tangles. However, as we review here, it has become increasingly clear that TAU causes damage much before these filamentous aggregates develop. In fact, because TAU is a scaffolding protein, increased levels and an altered subcellular localization (due to an increased insolubility and impaired clearance) result in the interaction of TAU with cellular proteins with which it would otherwise either not interact or do so to a lesser degree, thereby impairing their physiological functions. We specifically discuss the non-axonal localization of TAU, the role phosphorylation has in TAU toxicity and how TAU impairs mitochondrial functions. A major emphasis is on what we have learned from the four available TAU knock-out models in mice, and the knock-out of the TAU/MAP2 homolog PTL-1 in worms. It has been proposed that in human pathological conditions such as AD, a rare toxic TAU species exists which needs to be specifically removed to abrogate TAU's toxicity and restore neuronal functions. However, what is toxic in one context may not be in another, and simply reducing, but not fully abolishing TAU levels may be sufficient to abrogate TAU toxicity.
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Affiliation(s)
- Jürgen Götz
- Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
- Sydney Medical School, Brain and Mind Research Institute, University of Sydney, Sydney, NSW, Australia
| | - Di Xia
- Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Gerhard Leinenga
- Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Yee Lian Chew
- School of Molecular Bioscience, University of Sydney, Sydney, NSW, Australia
| | - Hannah R. Nicholas
- School of Molecular Bioscience, University of Sydney, Sydney, NSW, Australia
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24
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Köhler C, Dinekov M, Götz J. Active glycogen synthase kinase-3 and tau pathology-related tyrosine phosphorylation in pR5 human tau transgenic mice. Neurobiol Aging 2013; 34:1369-79. [DOI: 10.1016/j.neurobiolaging.2012.11.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 10/05/2012] [Accepted: 11/22/2012] [Indexed: 02/08/2023]
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Abstract
With populations ageing worldwide, the need for treating and preventing diseases associated with high age is pertinent. Alzheimer's disease (AD) is reaching epidemic proportions, yet the currently available therapies are limited to a symptomatic relief, without halting the degenerative process that characterizes the AD brain. As in AD cholinergic neurons are lost at high numbers, the initial strategies were limited to the development of acetylcholinesterase inhibitors, and more recently the NMDA receptor antagonist memantine, in counteracting excitotoxicity. With the identification of the protein tau in intracellular neurofibrillary tangles and of the peptide amyloid-β (Aβ) in extracellular amyloid plaques in the AD brain, and a better understanding of their role in disease, newer strategies are emerging, which aim at either preventing their formation and deposition or at accelerating their clearance. Interestingly, what is well established to combat viral diseases in peripheral organs - vaccination - seems to work for the brain as well. Accordingly, immunization strategies targeting Aβ show efficacy in mice and to some degree also in humans. Even more surprising is the finding in mice that immunization strategies targeting tau, a protein that forms aggregates in nerve cells, ameliorates the tau-associated pathology. We are reviewing the literature and discuss what can be expected regarding the translation into clinical practice and how the findings can be extended to other neurodegenerative diseases with protein aggregation in brain.
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Affiliation(s)
- Jürgen Götz
- Alzheimer's and Parkinson's Disease Laboratory, Brain & Mind Research Institute, University of Sydney, Camperdown, NSW, Australia.
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26
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Romberg C, Horner AE, Bussey TJ, Saksida LM. A touch screen-automated cognitive test battery reveals impaired attention, memory abnormalities, and increased response inhibition in the TgCRND8 mouse model of Alzheimer's disease. Neurobiol Aging 2012; 34:731-44. [PMID: 22959727 PMCID: PMC3532594 DOI: 10.1016/j.neurobiolaging.2012.08.006] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 06/21/2012] [Accepted: 08/09/2012] [Indexed: 12/12/2022]
Abstract
Transgenic mouse models of Alzheimer's disease (AD) with abundant β-amyloid develop memory impairments. However, multiple nonmnemonic cognitive domains such as attention and executive control are also compromised early in AD individuals, but have not been routinely assessed in animal models. Here, we assessed the cognitive abilities of TgCRND8 mice—a widely used model of β-amyloid pathology—with a touch screen-based automated test battery. The test battery comprises highly translatable tests of multiple cognitive constructs impaired in human AD, such as memory, attention, and response control, as well as appropriate control tasks. We found that familial AD mutations affect not only memory, but also cause significant alterations of sustained attention and behavioral flexibility. Because changes in attention and response inhibition may affect performance on tests of other cognitive abilities including memory, our findings have important consequences for the assessment of disease mechanisms and therapeutics in animal models of AD. A more comprehensive phenotyping with specialized, multicomponent cognitive test batteries for mice might significantly advance translation from preclinical mouse studies to the clinic.
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Affiliation(s)
- Carola Romberg
- Department of Experimental Psychology, University of Cambridge, Cambridge, UK.
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27
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Götz J, Matamales M, Götz NN, Ittner LM, Eckert A. Alzheimer's disease models and functional genomics-How many needles are there in the haystack? Front Physiol 2012; 3:320. [PMID: 22934069 PMCID: PMC3429089 DOI: 10.3389/fphys.2012.00320] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 07/23/2012] [Indexed: 11/25/2022] Open
Abstract
Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD) are complex human brain disorders that affect an increasing number of people worldwide. With the identification first of the proteins that aggregate in AD and FTLD brains and subsequently of pathogenic gene mutations that cause their formation in the familial cases, the foundation was laid for the generation of animal models. These recapitulate essential aspects of the human conditions; expression of mutant forms of the amyloid-β protein-encoding APP gene in mice reproduces amyloid-β (Aβ) plaque formation in AD, while that of mutant forms of the tau-encoding microtubule-associated protein tau (MAPT) gene reproduces tau-containing neurofibrillary tangle formation, a lesion that is also prevalent in FTLD-Tau. The mouse models have been complemented by those in lower species such as C. elegans or Drosophila, highlighting the crucial role for Aβ and tau in human neurodegenerative disease. In this review, we will introduce selected AD/FTLD models and discuss how they were instrumental, by identifying deregulated mRNAs, miRNAs and proteins, in dissecting pathogenic mechanisms in neurodegenerative disease. We will discuss some recent examples, which includes miRNA species that are specifically deregulated by Aβ, mitochondrial proteins that are targets of both Aβ and tau, and the nuclear splicing factor SFPQ that accumulates in the cytoplasm in a tau-dependent manner. These examples illustrate how a functional genomics approach followed by a careful validation in experimental models and human tissue leads to a deeper understanding of the pathogenesis of AD and FTLD and ultimately, may help in finding a cure.
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Affiliation(s)
- Jürgen Götz
- Centre for Ageing Dementia Research, Queensland Brain Institute, The University of QueenslandSt Lucia, QLD, Australia
| | - Miriam Matamales
- Centre for Ageing Dementia Research, Queensland Brain Institute, The University of QueenslandSt Lucia, QLD, Australia
| | - Naeman N. Götz
- Centre for Ageing Dementia Research, Queensland Brain Institute, The University of QueenslandSt Lucia, QLD, Australia
| | - Lars M. Ittner
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of SydneyCamperdown, NSW, Australia
| | - Anne Eckert
- Neurobiology Laboratory, Psychiatric University Clinics Basel, University of BaselBasel, Switzerland
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28
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Ke Y, Dramiga J, Schütz U, Kril JJ, Ittner LM, Schröder H, Götz J. Tau-mediated nuclear depletion and cytoplasmic accumulation of SFPQ in Alzheimer's and Pick's disease. PLoS One 2012; 7:e35678. [PMID: 22558197 PMCID: PMC3338448 DOI: 10.1371/journal.pone.0035678] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 03/20/2012] [Indexed: 11/19/2022] Open
Abstract
Tau dysfunction characterizes neurodegenerative diseases such as Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). Here, we performed an unbiased SAGE (serial analysis of gene expression) of differentially expressed mRNAs in the amygdala of transgenic pR5 mice that express human tau carrying the P301L mutation previously identified in familial cases of FTLD. SAGE identified 29 deregulated transcripts including Sfpq that encodes a nuclear factor implicated in the splicing and regulation of gene expression. To assess the relevance for human disease we analyzed brains from AD, Pick's disease (PiD, a form of FTLD), and control cases. Strikingly, in AD and PiD, both dementias with a tau pathology, affected brain areas showed a virtually complete nuclear depletion of SFPQ in both neurons and astrocytes, along with cytoplasmic accumulation. Accordingly, neurons harboring either AD tangles or Pick bodies were also depleted of SFPQ. Immunoblot analysis of human entorhinal cortex samples revealed reduced SFPQ levels with advanced Braak stages suggesting that the SFPQ pathology may progress together with the tau pathology in AD. To determine a causal role for tau, we stably expressed both wild-type and P301L human tau in human SH-SY5Y neuroblastoma cells, an established cell culture model of tau pathology. The cells were differentiated by two independent methods, mitomycin C-mediated cell cycle arrest or neuronal differentiation with retinoic acid. Confocal microscopy revealed that SFPQ was confined to nuclei in non-transfected wild-type cells, whereas in wild-type and P301L tau over-expressing cells, irrespective of the differentiation method, it formed aggregates in the cytoplasm, suggesting that pathogenic tau drives SFPQ pathology in post-mitotic cells. Our findings add SFPQ to a growing list of transcription factors with an altered nucleo-cytoplasmic distribution under neurodegenerative conditions.
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Affiliation(s)
- Yazi Ke
- Alzheimer's and Parkinson's Disease Laboratory, Brain & Mind Research Institute, University of Sydney, Camperdown, New South Wales, Australia
| | - Joe Dramiga
- Department II of Anatomy and Neuroanatomy, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, CMMC, University of Cologne, Cologne, Germany
| | - Ulrich Schütz
- Department II of Anatomy and Neuroanatomy, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, CMMC, University of Cologne, Cologne, Germany
| | - Jillian J. Kril
- Disciplines of Medicine and Pathology, University of Sydney, Sydney, New South Wales, Australia
| | - Lars M. Ittner
- Alzheimer's and Parkinson's Disease Laboratory, Brain & Mind Research Institute, University of Sydney, Camperdown, New South Wales, Australia
| | - Hannsjörg Schröder
- Department II of Anatomy and Neuroanatomy, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, CMMC, University of Cologne, Cologne, Germany
- * E-mail: (HS); (JG)
| | - Jürgen Götz
- Alzheimer's and Parkinson's Disease Laboratory, Brain & Mind Research Institute, University of Sydney, Camperdown, New South Wales, Australia
- * E-mail: (HS); (JG)
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Age-dependent axonal transport and locomotor changes and tau hypophosphorylation in a “P301L” tau knockin mouse. Neurobiol Aging 2012; 33:621.e1-621.e15. [DOI: 10.1016/j.neurobiolaging.2011.02.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 02/03/2011] [Accepted: 02/20/2011] [Indexed: 12/19/2022]
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ENU mutagenesis screen to establish motor phenotypes in wild-type mice and modifiers of a pre-existing motor phenotype in tau mutant mice. J Biomed Biotechnol 2011; 2011:130947. [PMID: 22219655 PMCID: PMC3246812 DOI: 10.1155/2011/130947] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 11/04/2011] [Indexed: 11/20/2022] Open
Abstract
Modifier screening is a powerful genetic tool. While not widely used in the vertebrate system, we applied these tools to transgenic mouse strains that recapitulate key aspects of Alzheimer's disease (AD), such as tau-expressing mice. These are characterized by a robust pathology including both motor and memory impairment. The phenotype can be modulated by ENU mutagenesis, which results in novel mutant mouse strains and allows identifying the underlying gene/mutation. Here we discuss this strategy in detail. We firstly obtained pedigrees that modify the tau-related motor phenotype, with mapping ongoing. We further obtained transgene-independent motor pedigrees: (i) hyperactive, circling ENU 37 mice with a causal mutation in the Tbx1 gene—the complete knock-out of Tbx1 models DiGeorge Syndrome; (ii) ENU12/301 mice that show sudden jerky movements and tremor constantly; they have a causal mutation in the Kcnq1 gene, modelling aspects of the Romano-Ward and Jervell and Lange-Nielsen syndromes; and (iii) ENU16/069 mice with tremor and hypermetric gait that have a causal mutation in the Mpz (Myelin Protein Zero) gene, modelling Charcot-Marie-Tooth disease type 1 (CMT1B). Together, we provide evidence for a real potential of an ENU mutagenesis to dissect motor functions in wild-type and tau mutant mice.
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Recent rodent models for Alzheimer's disease: clinical implications and basic research. J Neural Transm (Vienna) 2011; 119:173-95. [PMID: 22086139 DOI: 10.1007/s00702-011-0731-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Accepted: 10/24/2011] [Indexed: 01/27/2023]
Abstract
Alzheimer's disease (AD) is the most common origin of dementia in the elderly. Although the cause of AD remains unknown, several factors have been identified that appear to play a critical role in the development of this debilitating disorder. In particular, amyloid precursor protein (APP), tau hyperphosphorylation, and the secretase enzymes, have become the focal point of recent research. Over the last two decades, several transgenic and non-transgenic animal models have been developed to elucidate the mechanistic aspects of AD and to validate potential therapeutic targets. Transgenic rodent models over-expressing human β-amyloid precursor protein (β-APP) and mutant forms of tau have become precious tools to study and understand the pathogenesis of AD at the molecular, cellular and behavioural levels, and to test new therapeutic agents. Nevertheless, none of the transgenic models of AD recapitulate fully all of the pathological features of the disease. Octodon degu, a South American rodent has been recently found to spontaneously develop neuropathological signs of AD in old age. This review aims to address the limitations and clinical relevance of transgenic rodent models in AD, and to highlight the potential for O. degu as a natural model for the study of AD neuropathology.
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Modes of Aβ toxicity in Alzheimer's disease. Cell Mol Life Sci 2011; 68:3359-75. [PMID: 21706148 PMCID: PMC3181413 DOI: 10.1007/s00018-011-0750-2] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 06/01/2011] [Accepted: 06/06/2011] [Indexed: 12/18/2022]
Abstract
Alzheimer’s disease (AD) is reaching epidemic proportions, yet a cure is not yet available. While the genetic causes of the rare familial inherited forms of AD are understood, the causes of the sporadic forms of the disease are not. Histopathologically, these two forms of AD are indistinguishable: they are characterized by amyloid-β (Aβ) peptide-containing amyloid plaques and tau-containing neurofibrillary tangles. In this review we compare AD to frontotemporal dementia (FTD), a subset of which is characterized by tau deposition in the absence of overt plaques. A host of transgenic animal AD models have been established through the expression of human proteins with pathogenic mutations previously identified in familial AD and FTD. Determining how these mutant proteins cause disease in vivo should contribute to an understanding of the causes of the more frequent sporadic forms. We discuss the insight transgenic animal models have provided into Aβ and tau toxicity, also with regards to mitochondrial function and the crucial role tau plays in mediating Aβ toxicity. We also discuss the role of miRNAs in mediating the toxic effects of the Aβ peptide.
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Attems J, Ittner A, Jellinger K, Nitsch RM, Maj M, Wagner L, Götz J, Heikenwalder M. Reduced secretagogin expression in the hippocampus of P301L tau transgenic mice. J Neural Transm (Vienna) 2011; 118:737-45. [PMID: 21442354 DOI: 10.1007/s00702-011-0626-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Accepted: 03/13/2011] [Indexed: 11/26/2022]
Abstract
Neuropathological features in Alzheimer's Disease (AD) include the presence of hyperphosphorylated forms of the microtubule-associated tau protein (tau) in hippocampal neurones. Numerous studies indicate a neuroprotective effect of calcium-binding proteins (Ca2+ binding proteins) in neurodegenerative diseases (e.g., AD). Secretagogin is a newly described Ca2+ binding protein that is produced by pyramidal neurones of the human hippocampus. Recently, secretagogin expressing hippocampal neurones were demonstrated to resist tau-induced pathology in AD in contrast to the majority of neighbouring neurones. This suggested a neuroprotective effect of secretagogin in hippocampal neurones. Here, we investigated secretagogin expression in wild type (wt) mice as well as in hemizygous and homozygous P301L tau transgenic (tg) mice, which show pronounced and widespread tau pathology in hippocampal neurones. Secretagogin expression was analyzed at the immunohistochemical and biochemical levels in brains of age-matched wt and hemi- and homozygous tau tg mice. In wt mice hippocampal secretagogin-immunoreactive neurones were invariably detected, while immunoreactivity was much lower (P < 0.001) in tau tg mice. Of note, hippocampal secretagogin immunoreactivity was absent in 62.5% of homozygous tau tg mice. In line with this finding, Western blot analysis demonstrated a significant reduction in protein expression levels of secretagogin in homozygous tau tg compared to wt mice. Our results suggest that increased levels of tau negatively influence secretagogin expression in the hippocampus of tau tg mice.
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Affiliation(s)
- Johannes Attems
- Institute for Ageing and Health, Wolfson Research Centre, Newcastle University, Newcastle upon Tyne, UK.
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Götz J, Gladbach A, Pennanen L, van Eersel J, Schild A, David D, Ittner LM. Animal models reveal role for tau phosphorylation in human disease. Biochim Biophys Acta Mol Basis Dis 2010; 1802:860-71. [DOI: 10.1016/j.bbadis.2009.09.008] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 09/03/2009] [Accepted: 09/07/2009] [Indexed: 12/18/2022]
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van Eersel J, Ke YD, Liu X, Delerue F, Kril JJ, Götz J, Ittner LM. Sodium selenate mitigates tau pathology, neurodegeneration, and functional deficits in Alzheimer's disease models. Proc Natl Acad Sci U S A 2010; 107:13888-93. [PMID: 20643941 PMCID: PMC2922247 DOI: 10.1073/pnas.1009038107] [Citation(s) in RCA: 209] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Alzheimer's disease (AD) brains are characterized by amyloid-beta-containing plaques and hyperphosphorylated tau-containing neurofibrillary tangles (NFTs); however, in frontotemporal dementia, the tau pathology manifests in the absence of overt amyloid-beta plaques. Therapeutic strategies so far have primarily been targeting amyloid-beta, although those targeting tau are only slowly beginning to emerge. Here, we identify sodium selenate as a compound that reduces tau phosphorylation both in vitro and in vivo. Importantly, chronic oral treatment of two independent tau transgenic mouse strains with NFT pathology, P301L mutant pR5 and K369I mutant K3 mice, reduces tau hyperphosphorylation and completely abrogates NFT formation. Furthermore, treatment improves contextual memory and motor performance, and prevents neurodegeneration. As hyperphosphorylation of tau precedes NFT formation, the effect of selenate on tau phosphorylation was assessed in more detail, a process regulated by both kinases and phosphatases. A major phosphatase implicated in tau dephosphorylation is the serine/threonine-specific protein phosphatase 2A (PP2A) that is reduced in both levels and activity in the AD brain. We found that selenate stabilizes PP2A-tau complexes. Moreover, there was an absence of therapeutic effects in sodium selenate-treated tau transgenic mice that coexpress a dominant-negative mutant form of PP2A, suggesting a mediating role for PP2A. Taken together, sodium selenate mitigates tau pathology in several AD models, making it a promising lead compound for tau-targeted treatments of AD and related dementias.
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Affiliation(s)
- Janet van Eersel
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, Camperdown, New South Wales 2050, Australia; and
- Department of Pathology, University of Sydney, Camperdown, New South Wales 2016, Australia
| | - Yazi D. Ke
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, Camperdown, New South Wales 2050, Australia; and
| | - Xin Liu
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, Camperdown, New South Wales 2050, Australia; and
| | - Fabien Delerue
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, Camperdown, New South Wales 2050, Australia; and
| | - Jillian J. Kril
- Department of Pathology, University of Sydney, Camperdown, New South Wales 2016, Australia
| | - Jürgen Götz
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, Camperdown, New South Wales 2050, Australia; and
| | - Lars M. Ittner
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, Camperdown, New South Wales 2050, Australia; and
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Köhler C, Bista P, Götz J, Schröder H. Analysis of the cholinergic pathology in the P301L tau transgenic pR5 model of tauopathy. Brain Res 2010; 1347:111-24. [DOI: 10.1016/j.brainres.2010.05.076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 05/21/2010] [Accepted: 05/24/2010] [Indexed: 01/28/2023]
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Convergence of amyloid-beta and tau pathologies on mitochondria in vivo. Mol Neurobiol 2010; 41:107-14. [PMID: 20217279 PMCID: PMC2876263 DOI: 10.1007/s12035-010-8109-5] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Accepted: 02/12/2010] [Indexed: 12/14/2022]
Abstract
The histopathological characteristics of Alzheimer’s disease (AD) are amyloid-β (Aβ) containing plaques and neurofibrillary tangles (NFTs) as well as neuronal and synaptic loss. Until today, the underlying mechanisms of the interplay of plaques and tangles remained unresolved. There is increasing evidence that mitochondrial dysfunction might be a possible link, as revealed by studies in several APP and tau transgenic mouse models. Recently, we examined mitochondrial function in a novel triple transgenic mouse model (pR5/APP/PS2)—tripleAD mice—that combines both pathologic features of the disease in brain. Using comparative, quantitative proteomics (iTRAQ) and mass spectroscopy, we found a massive deregulation of 24 proteins, of which one third were mitochondrial proteins mainly related to complexes I and IV of the oxidative phosphorylation system (OXPHOS). Remarkably, deregulation of complex I was related to tau, whereas deregulation of complex IV was Aβ dependent, both at the protein and activity levels. The tripleAD mice showed synergistic effects of Aβ and tau already at the age of 8 months, resulting in a depolarized mitochondrial membrane potential. At 12 months, the strongest defects on OXPHOS, synthesis of ATP and reactive oxygen species, were exhibited in the tripleAD mice, again emphasizing synergistic, age-associated effects of Aβ and tau in impairing mitochondria. This review highlights the convergence of Aβ and tau on mitochondria and establishes a molecular link in AD pathology in vivo.
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SJLB mice develop tauopathy-induced parkinsonism. Neurosci Lett 2010; 473:182-5. [PMID: 20178834 DOI: 10.1016/j.neulet.2010.02.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 02/09/2010] [Accepted: 02/15/2010] [Indexed: 11/20/2022]
Abstract
Frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) is an inherited dementia caused by tauopathy. Recently, we established the N279K mutant human tau transgenic mice SJLB. Although SJLB mice show cognitive dysfunction with insoluble tau in the brain, it has remained unclear whether they show signs of parkinsonism. To clarify this issue, we studied whether SJLB mice in fact develop parkinsonism. Behavioral analysis showed shorter stride length than that of non-transgenic control mice in the footprint test and movement disorder in the pole test, thus mimicking some features of human parkinsonism. We also found that these symptoms were not affected by dopamine treatment. These results indicate that SJLB mice show signs of parkinsonism and they could be of usefulness not only for studies of dementing disease but also of parkinsonism induced by tauopathy.
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Scattoni ML, Gasparini L, Alleva E, Goedert M, Calamandrei G, Spillantini MG. Early behavioural markers of disease in P301S tau transgenic mice. Behav Brain Res 2009; 208:250-7. [PMID: 20004218 DOI: 10.1016/j.bbr.2009.12.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/01/2009] [Accepted: 12/02/2009] [Indexed: 10/20/2022]
Abstract
The present study aimed at characterizing the early behavioural changes preceding the onset of disease in a transgenic mouse model of tauopathy. Mice transgenic for human P301S tau protein exhibit many characteristics of human tauopathies, including neurodegeneration, the formation of neuronal tau inclusions in the brain and the development of a pronounced motor phenotype by 5 months of age. In this study we analyzed the ultrasonic vocalization pattern in the first week of life and the response to nest-related olfactory stimuli on postnatal day 10 in both homozygous and heterozygous transgenic mice in comparison with the behavioural responses of C57BL/6J pups. Expression of human tau in the brain and spinal cord was evaluated by Western blot analysis. Homozygous P301S tau transgenic and C57BL/6J mice were also assessed for motor coordination in the Rotarod apparatus at 1, 2, 3 and 4 months of age, and spatial learning and spontaneous behaviour were evaluated at 2 months in the Morris water-maze and the open-field test. Results showed that P301S pups emitted more ultrasounds than C57BL/6J pups when separated from the mother. Two-month-old P301S mice displayed a hyperactive profile, as shown by increased swimming speed, enhanced locomotion and exploration of a novel object in the open field. However, the spatial task acquisition was unaltered. Decline of motor coordination capacities was evident only by the third month of age in the rotarod test. Behavioural abnormalities can be detected well before occurrence of neurodegeneration in this transgenic strain, thus representing precocious markers of pathology.
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Affiliation(s)
- Maria Luisa Scattoni
- Neurotoxicology and Neuroendocrinology Section, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy.
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Abstract
In dementia research, animal models have become indispensable tools. They not only model aspects of the human condition, but also simulate processes that occur in humans and hence provide insight into how disease is initiated and propagated. The present review discusses two prominent human neurodegenerative disorders, Alzheimer's disease and frontotemporal dementia. It discusses what we would like to model in animals and highlights some of the more recent achievements using species as diverse as mice, fish, flies and worms. Advances in imaging and therapy are explored. We also discuss some anticipated new models and developments. These will reveal how key players in the pathogenesis of Alzheimer's disease and frontotemporal dementia, such as the peptide Aβ (amyloid β) and the protein tau, cause neuronal dysfunction and eventually, neuronal demise. Understanding these processes fully will lead to early diagnosis and therapy.
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Zilka N, Korenova M, Novak M. Misfolded tau protein and disease modifying pathways in transgenic rodent models of human tauopathies. Acta Neuropathol 2009; 118:71-86. [PMID: 19238406 DOI: 10.1007/s00401-009-0499-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 02/05/2009] [Accepted: 02/09/2009] [Indexed: 12/24/2022]
Abstract
Human tauopathies represent a heterogeneous group of neurodegenerative disorders such as Alzheimer's disease (AD) that are characterized by the presence of intracellular accumulations of abnormal filaments of protein tau. Presently, AD poses an increasing public health concern, because it affects nearly 2% of the population in industrialized countries and the number of patients is expected to increase threefold within the next 50 years. Therefore, the identification of disease modifying pathways that will lead to the development of novel therapeutic approaches targeting downstream molecular events of the tauopathy is of paramount importance. In order to identify factors that may exacerbate or inhibit the disease phenotype a number of genetically modified rodent models reproducing key clinical, histopathological and molecular hallmarks of human tauopathies were developed. Current tau transgenic rodent models express as a transgene either an individual or all six human wild-type tau isoforms, mutant tau linked to FTDP-17, or structurally modified tau species derived from AD. In this review we will provide an up-to-date account of various facets of the tau neurodegenerative cascade with a special emphasis on the evolution of neurofibrillary tangles, neuronal death and neuroinflammation.
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Affiliation(s)
- Norbert Zilka
- Centre of Excellence for Alzheimer's Disease and Related Disorders, Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska 9, 84510 Bratislava, Slovak Republic
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Nishimura T, Kubosaki A, Ito Y, Notkins AL. Disturbances in the secretion of neurotransmitters in IA-2/IA-2beta null mice: changes in behavior, learning and lifespan. Neuroscience 2009; 159:427-37. [PMID: 19361477 DOI: 10.1016/j.neuroscience.2009.01.022] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 12/24/2008] [Accepted: 01/07/2009] [Indexed: 11/15/2022]
Abstract
Islet-associated protein 2 (IA-2) and IA-2beta are major autoantigens in type 1 diabetes and transmembrane proteins in dense core secretory vesicles (DCV) of neuroendocrine cells. The deletion of these genes results in a decrease in insulin secretion. The present study was initiated to test the hypothesis that this deletion not only affects the secretion of insulin, but has a more global effect on neuroendocrine secretion that leads to disturbances in behavior and learning. Measurement of neurotransmitters showed that norepinephrine, dopamine and 5-HT were significantly decreased in the brain of double knockout (DKO) mice (P<0.05 to <0.001). In tests evaluating anxiety-like behavior and conditioned-learning, the DKO mice showed a highly significant increase in anxiety-like behavior (P<0.01 to <0.001) and impairment of conditioned learning (P<0.01) as compared to WT mice. The DKO mice also displayed an increase in spontaneous and induced seizures (P<0.01) and age-related death. Contrary to the generally held view that IA-2 and IA-2beta are expressed exclusively in DCV, subcellular fractionation studies revealed that IA-2beta, but not IA-2, co-purifies with fractions rich in synaptic vesicles (SV), and that the secretion of dopamine, GABA and glutamate from the synaptosomes of the DKO mice was significantly decreased as was the number of SV (P<0.01). Taken together, these findings show that IA-2beta is present in both DCV and SV, and that the deletion of IA-2/IA-2beta has a global effect on the secretion of neurotransmitters. The impairment of secretion leads to behavioral and learning disturbances, seizures and reduced lifespan.
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Affiliation(s)
- T Nishimura
- Experimental Medicine Section, Oral Infection and Immunity Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4322, USA
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Hanna A, Horne P, Yager D, Eckman C, Eckman E, Janus C. Amyloid beta and impairment in multiple memory systems in older transgenic APP TgCRND8 mice. GENES BRAIN AND BEHAVIOR 2009; 8:676-84. [PMID: 19531156 DOI: 10.1111/j.1601-183x.2009.00510.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The relationship between amyloid beta and cognitive dysfunction in mouse models of Alzheimer's disease has been evaluated predominantly with the spatial reference memory version of the water maze task. However, as Alzheimer's disease encompasses decline in multiple memory systems, it is important to also utilize non-spatial tasks to fully characterize the role of amyloid on behaviour in animal models. We used the TgCRND8 mouse model of Alzheimer's disease to evaluate the effect of amyloid on spatial reference memory, as well as on the non-spatial task of acquisition of conditioned taste aversion, and on the procedural task of swimming to a visible platform. We demonstrate that 8- to 12-month-old TgCRND8 mice are significantly impaired in all three tasks, and that the levels of soluble amyloid beta are significantly correlated with impairment in spatial reference memory, but not with impairment in conditioned taste aversion or swimming to a visible platform. Insoluble fractions of amyloid, which correspond closely to amyloid plaque burden in the brain, are not associated with any behavioural measure. Our study extends the characterization of the model to stages of advanced amyloid pathology and demonstrates that older TgCRND8 mice are impaired in multiple memory systems, including procedural tasks, which are spared at younger ages. The lack of association between amyloid plaques and memory decline supports clinical findings in Alzheimer's patients.
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Affiliation(s)
- A Hanna
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
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Korenova M, Stozicka Z. Improved behavioral response as a valid biomarker for drug screening program in transgenic rodent models of tauopathies. Cell Mol Neurobiol 2009; 29:937-44. [PMID: 19283467 DOI: 10.1007/s10571-009-9378-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 02/24/2009] [Indexed: 11/25/2022]
Abstract
Neurodegenerative tauopathies are defined as a group of dementia and movement disorders characterized by prominent filamentous tau inclusions and degeneration located within certain brain regions. Their common sign is a presence of proteinaceous aggregates composed of hyperphosphorylated and truncated tau proteins. The molecular mechanisms of the disease still remain unresolved, therefore transgenic organisms displaying tau-related neurodegenerative cascade have been created to allow decoding of individual pathways involved in human pathological conditions. Moreover, use of transgenic model organisms enables the application of potential therapeutic approaches. The expression of mutated or misfolded tau as a transgene in vivo leads to significant alteration of neurobehavioral features of experimental animal, therefore detailed classification of behavioral phenotype become one of the first crucial analyses, while it functionally correlates with central nervous system impairment. Currently, two major types of behavioral impairment have been described in transgenic rodent models of tauopathies, (1) progressive motor impairment associated with muscular weakness and premature death and (2) age-related impairment of cognitive functions attended with unaffected motor status. Up to the present, only transgenic models displaying motor impairment were successfully applied into the drug trials targeting misfolded tau protein, despite their behavioral inconsistence with clinical profile of progressive human tauopathy. The aim of this study was, therefore, to summarize the pros and cons of used transgenic rodent models mimicking human tauopathies in connection with development of therapeutic strategies.
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Affiliation(s)
- Miroslava Korenova
- Institute of Neuroimmunology, Slovak Academy of Sciences, AD Centre, Bratislava 845 10, Slovak Republic.
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Denk F, Wade-Martins R. Knock-out and transgenic mouse models of tauopathies. Neurobiol Aging 2009; 30:1-13. [PMID: 17590238 PMCID: PMC2806682 DOI: 10.1016/j.neurobiolaging.2007.05.010] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Revised: 05/04/2007] [Accepted: 05/11/2007] [Indexed: 12/26/2022]
Abstract
Tauopathies, characterized by the dysfunction and aggregation of the microtubule-associated protein tau (MAPT), represent some of the most devastating neurodegenerative disorders afflicting the elderly, including Alzheimer's disease and progressive supranuclear palsy. Here we review the range of Mapt knock-out and MAPT transgenic mouse models which have proven successful at providing insights into the molecular mechanisms of neurodegenerative disease. In this overview we highlight several themes, including the insights such models provide into the cellular and molecular mechanisms of tauopathy, the direct relationship between neuropathology and behaviour, and the use of mouse models to help provide a platform for testing novel therapies. Mouse models have helped clarify the relationship between pathological forms of tau, cell death, and the emergence of disease, as well as the interaction between tau and other disease-associated molecules, such as the A beta peptide. Finally, we discuss potential future MAPT genomic DNA models to investigate the importance of alternative splicing of the MAPT locus and its role in sporadic tauopathies.
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Affiliation(s)
- Franziska Denk
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, United Kingdom.
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Götz J, Ittner LM, Schonrock N, Cappai R. An update on the toxicity of Abeta in Alzheimer's disease. Neuropsychiatr Dis Treat 2008; 4:1033-42. [PMID: 19337449 PMCID: PMC2646638 DOI: 10.2147/ndt.s3016] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Alzheimer's disease is characterized histopathologically by deposition of insoluble forms of the peptide Abeta and the protein tau in brain. Abeta is the principal component of amyloid plaques and tau of neurofibrillary tangles. Familial cases of AD are associated with causal mutations in the gene encoding the amyloid precursor protein, APP, from which the amyloidogenic Abeta peptide is derived, and this supports a role for Abeta in disease. Abeta can promote tau pathology and at the same time its toxicity is also tau-dependent. Abeta can adopt different conformations including soluble oligomers and insoluble fibrillar species present in plaques. We discuss which of these conformations exert toxicity, highlight molecular pathways involved and discuss what has been learned by applying functional genomics.
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Affiliation(s)
- Jürgen Götz
- Alzheimer's and Parkinson's Disease Laboratory, Brain and Mind Research Institute, University of Sydney, 100 Mallett St, Camperdown, NSW 2050, Australia.
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Deters N, Ittner LM, Götz J. Divergent phosphorylation pattern of tau in P301L tau transgenic mice. Eur J Neurosci 2008; 28:137-47. [PMID: 18662339 DOI: 10.1111/j.1460-9568.2008.06318.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Aggregates of hyperphosphorylated tau are prominent in brains of patients with Alzheimer's disease or frontotemporal dementia (FTD). They have been reproduced in animal models following the identification of tau mutations in familial cases of FTD. This includes our previously generated transgenic model, pR5, which expresses FTD (P301L) mutant tau in neurons. The mice are characterized by tau aggregation including tangle (NFT) formation, memory impairment and mitochondrial dysfunction. In 8-month-old mice, S422 phosphorylation of tau is linked to NFT formation, however, a detailed analysis of tau solubility, phosphorylation and aggregation has not been done nor have the mice been monitored until a high age. Here, we undertook an analysis by immunohistochemistry, Gallyas impregnation and Western blotting of brains from 3 month- up to 20 month-old mice. NFTs first appeared at 6 months in the amygdala, followed by the CA1 region of the hippocampus. As the mice get older, the solubility of tau is decreased as determined by sequential extractions. Histological analysis revealed increased phosphorylation at the AT180, AT270 and 12E8 epitopes with ageing. The numbers of AT8-positive neurons increased from 3 to 6 months old. However, whereas S422 appeared only late and concomitantly with NFT formation, the only neurons left with AT8-reactivity at 20 months were those that had undergone NFT formation. As hyperphosphorylated tau continued to accumulate, the lack of AT8-reactivity suggests regulatory mechanisms in specifically dephosphorylating the AT8 epitope in the remaining neurons. Thus, differential regulation of phosphorylation is important for NFT formation in neurodegenerative diseases with tau pathology.
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Affiliation(s)
- Natasha Deters
- Alzheimer's and Parkinson's Disease Laboratory, Brain & Mind Research Institute, University of Sydney, 100 Mallett St, Camperdown, NSW 2050, Australia
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Oligomeric and fibrillar species of beta-amyloid (A beta 42) both impair mitochondrial function in P301L tau transgenic mice. J Mol Med (Berl) 2008; 86:1255-67. [PMID: 18709343 DOI: 10.1007/s00109-008-0391-6] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Revised: 07/18/2008] [Accepted: 07/21/2008] [Indexed: 01/19/2023]
Abstract
We recently provided evidence for a mitochondrial dysfunction in P301L tau transgenic mice, a strain modeling the tau pathology of Alzheimer's disease (AD) and frontotemporal dementia (FTD). In addition to tau aggregates, the AD brain is further characterized by A beta peptide-containing plaques. When we addressed the role of A beta, this indicated a synergistic action of tau and A beta pathology on the mitochondria. In the present study, we compared the toxicity of different A beta 42 conformations in light of recent studies suggesting that oligomeric rather than fibrillar A beta might be the actual toxic species. Interestingly, both oligomeric and fibrillar, but not disaggregated (mainly monomeric) A beta 42 caused a decreased mitochondrial membrane potential in cortical brain cells obtained from FTD P301L tau transgenic mice. This was not observed with cerebellar preparations indicating selective vulnerability of cortical neurons. Furthermore, we found reductions in state 3 respiration, the respiratory control ratio, and uncoupled respiration when incubating P301L tau mitochondria either with oligomeric or fibrillar preparations of A beta 42. Finally, we found that aging specifically increased the sensitivity of mitochondria to oligomeric A beta 42 damage indicating that oligomeric and fibrillar A beta 42 are both toxic, but exert different degrees of toxicity.
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Cassel JC, Mathis C, Majchrzak M, Moreau PH, Dalrymple-Alford JC. Coexisting cholinergic and parahippocampal degeneration: a key to memory loss in dementia and a challenge for transgenic models? NEURODEGENER DIS 2008; 5:304-17. [PMID: 18520165 DOI: 10.1159/000135615] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Accepted: 10/31/2007] [Indexed: 12/25/2022] Open
Abstract
One century after Alzheimer's initial report, a variety of animal models of Alzheimer's disease (AD) are being used to mimic one or more pathological signs viewed as critical for the evolution of cognitive decline in dementia. Among the most common are, (a) traditional lesion models aimed at reproducing the degeneration of one of two key brain regions affected in AD, namely the cholinergic basal forebrain (CBF) and the transentorhinal region, and (b) transgenic mouse models aimed at reproducing AD histopathological hallmarks, namely amyloid plaques and neurofibrillary tangles. These models have provided valuable insights into the development and consequences of the pathology, but they have not consistently reproduced the severity of memory deficits exhibited in AD. The reasons for this lack of correspondence with the severity of expected deficits may include the limited replication of multiple neuropathology in potentially key brain regions. A recent lesion model in the rat found that severe memory impairment was obtained only when the two traditional lesions were combined together (i.e. conjoint CBF and entorhinal cortex lesions), indicative of a dramatic impact on cognitive function when there is coexisting, rather than isolated, damage in these two brain regions. It is proposed that combining AD transgenic mouse models with additional experimental damage to both the CBF and entorhinal regions might provide a unique opportunity to further understand the evolution of the disease and improve treatments of severe cognitive dysfunction in neurodegenerative dementias.
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Affiliation(s)
- Jean-Christophe Cassel
- LINC UMR 7191, Université Louis Pasteur, CNRS, Institut Fédératif de Recherche IFR 37, GDR CNRS 2905, Strasbourg, France.
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Pistell PJ, Zhu M, Ingram DK. Acquisition of conditioned taste aversion is impaired in the amyloid precursor protein/presenilin 1 mouse model of Alzheimer's disease. Neuroscience 2008; 152:594-600. [PMID: 18304749 DOI: 10.1016/j.neuroscience.2008.01.025] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 01/16/2008] [Accepted: 01/21/2008] [Indexed: 11/25/2022]
Abstract
Research into the underlying mechanisms of cognitive dysfunction in Alzheimer's disease (AD) has relied traditionally on tasks such as the water maze which evaluate spatial learning and memory. Since non-spatial forms of memory are also disrupted by AD, it is critical to establish other paradigms capable of investigating these deficits. Utilizing a non-spatial learning task, acquisition of conditioned taste aversion (CTA) was evaluated in a mouse model of AD. This line of transgenic mice encode a mutated allele of the human amyloid precursor protein (APP) and presenilin 1 (PS1) genes and exhibit extensive amyloid plaque deposition in the brain by 6-7 mo of age. Compared with wild-type mice, 10-17 month old APP/PS1 mice failed to acquire CTA to saccharin. Mice that only possessed one of the two mutations were able to acquire CTA to the saccharin. In 2-5 month old APP/PS1 mice acquisition of CTA was disrupted despite the lack of extensive plaque deposition. However, further analysis indicated a potential gender difference in both the CTA deficit and onset of plaque deposition with females showing greater conditioned aversion.
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Affiliation(s)
- P J Pistell
- Behavioral Neuroscience Section, Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, Gerontology Research Center, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA.
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