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Stazi M, Zampar S, Klafki HW, Meyer T, Wirths O. A Combination of Caffeine Supplementation and Enriched Environment in an Alzheimer's Disease Mouse Model. Int J Mol Sci 2023; 24:ijms24032155. [PMID: 36768476 PMCID: PMC9916825 DOI: 10.3390/ijms24032155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/12/2023] [Accepted: 01/20/2023] [Indexed: 01/25/2023] Open
Abstract
A variety of factors has been associated with healthy brain aging, and epidemiological studies suggest that physical activity and nutritional supplements such as caffeine may reduce the risk of developing dementia and, in particular, Alzheimer's disease (AD) in later life. Caffeine is known to act as a cognitive enhancer but has been also shown to positively affect exercise performance in endurance activities. We have previously observed that chronic oral caffeine supplementation and a treatment paradigm encompassing physical and cognitive stimulation by enriched environment (EE) housing can improve learning and memory performance and ameliorate hippocampal neuron loss in the Tg4-42 mouse model of AD. Here, we investigated whether these effects were synergistic. To that end, previous findings on individual treatments were complemented with unpublished, additional data and analyzed in depth by ANOVA followed by Bonferroni multiple comparison post tests. We further evaluated whether plasma neurofilament light chain levels reflect neuropathological and behavioral changes observed in the experimental groups. While a treatment combining physical activity and caffeine supplementation significantly improved learning and memory function compared to standard-housed vehicle-treated Tg4-42 in tasks such as the Morris water maze, no major additive effect outperforming the effects of the single interventions was observed.
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Affiliation(s)
- Martina Stazi
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Silvia Zampar
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Hans-Wolfgang Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Thomas Meyer
- Department of Psychosomatic Medicine, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
- Correspondence:
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Curdt N, Schmitt FW, Bouter C, Iseni T, Weile HC, Altunok B, Beindorff N, Bayer TA, Cooke MB, Bouter Y. Search strategy analysis of Tg4-42 Alzheimer Mice in the Morris Water Maze reveals early spatial navigation deficits. Sci Rep 2022; 12:5451. [PMID: 35361814 PMCID: PMC8971530 DOI: 10.1038/s41598-022-09270-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 03/18/2022] [Indexed: 12/20/2022] Open
Abstract
Spatial disorientation is one of the earliest symptoms in Alzheimer’s disease and allocentric deficits can already be detected in the asymptomatic preclinical stages of the disease. The Morris Water Maze (MWM) is used to study spatial learning in rodent models. Here we investigated the spatial memory of female 3, 7 and 12 month-old Alzheimer Tg4-42 mice in comparison to wild-type control animals. Conventional behavior analysis of escape latencies and quadrant preference revealed spatial memory and reference memory deficits in female 7 and 12 month-old Tg4-42 mice. In contrast, conventional analysis of the MWM indicated an intact spatial memory in 3 month-old Tg4-42 mice. However, a detailed analysis of the swimming strategies demonstrated allocentric-specific memory deficits in 3 month-old Tg4-42 mice before the onset of severe memory deficits. Furthermore, we could show that the spatial reference memory deficits in aged Tg4-42 animals are caused by the lack of allocentric and spatial strategies. Analyzing search strategies in the MWM allows to differentiate between hippocampus-dependent allocentric and hippocampus-independent egocentric search strategies. The spatial navigation impairments in young Tg4-42 mice are well in line with the hypometabolism and synaptic deficits in the hippocampus. Therefore, analyzing search strategies in the Tg4-42 model can be a powerful tool for preclinical drug testing and identifying early therapeutic successes.
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Affiliation(s)
- Nadine Curdt
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany
| | - Franziska W Schmitt
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany
| | - Caroline Bouter
- Department of Nuclear Medicine, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Trendelina Iseni
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany
| | - Hanna C Weile
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany
| | - Berfin Altunok
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany
| | - Nicola Beindorff
- Berlin Experimental Radionuclide Imaging Center (BERIC), Charité-University Medicine Berlin, Berlin, Germany
| | - Thomas A Bayer
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany
| | - Matthew B Cooke
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.,Department of Psychology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Yvonne Bouter
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075, Göttingen, Germany.
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Marengo L, Armbrust F, Schoenherr C, Storck SE, Schmitt U, Zampar S, Wirths O, Altmeppen H, Glatzel M, Kaether C, Weggen S, Becker-Pauly C, Pietrzik CU. Meprin β knockout reduces brain Aβ levels and rescues learning and memory impairments in the APP/lon mouse model for Alzheimer's disease. Cell Mol Life Sci 2022; 79:168. [PMID: 35235058 PMCID: PMC8891209 DOI: 10.1007/s00018-022-04205-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 01/26/2022] [Accepted: 02/10/2022] [Indexed: 11/25/2022]
Abstract
β-Site amyloid precursor protein (APP) cleaving enzyme-1 (BACE1) is the major described β-secretase to generate Aβ peptides in Alzheimer's disease (AD). However, all therapeutic attempts to block BACE1 activity and to improve AD symptoms have so far failed. A potential candidate for alternative Aβ peptides generation is the metalloproteinase meprin β, which cleaves APP predominantly at alanine in p2 and in this study we can detect an increased meprin β expression in AD brain. Here, we report the generation of the transgenic APP/lon mouse model of AD lacking the functional Mep1b gene (APP/lon × Mep1b-/-). We examined levels of canonical and truncated Aβ species using urea-SDS-PAGE, ELISA and immunohistochemistry in brains of APP/lon mouse × Mep1b-/-. Additionally, we investigated the cognitive abilities of these mice during the Morris water maze task. Aβ1-40 and 1-42 levels are reduced in APP/lon mice when meprin β is absent. Immunohistochemical staining of mouse brain sections revealed that N-terminally truncated Aβ2-x peptide deposition is decreased in APP/lon × Mep1b-/- mice. Importantly, loss of meprin β improved cognitive abilities and rescued learning behavior impairments in APP/lon mice. These observations indicate an important role of meprin β within the amyloidogenic pathway and Aβ production in vivo.
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Affiliation(s)
- Liana Marengo
- Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Fred Armbrust
- Institute of Biochemistry, Unit for Degradomics of the Protease Web, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Caroline Schoenherr
- Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Steffen E. Storck
- Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Ulrich Schmitt
- Leibniz-Institute for Resilience Research, Mainz, Germany
| | - Silvia Zampar
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Hermann Altmeppen
- Institute of Neuropathology, University Medical Center HH-Eppendorf, Hamburg, Germany
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center HH-Eppendorf, Hamburg, Germany
| | | | - Sascha Weggen
- Department of Neuropathology, Heinrich Heine University, Düsseldorf, Germany
| | - Christoph Becker-Pauly
- Institute of Biochemistry, Unit for Degradomics of the Protease Web, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Claus U. Pietrzik
- Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Molecular Neurodegeneration, Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg University of Mainz, Duesbergweg 6, 55099 Mainz, Germany
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Discovery of a novel pseudo β-hairpin structure of N-truncated amyloid-β for use as a vaccine against Alzheimer's disease. Mol Psychiatry 2022; 27:840-848. [PMID: 34776512 DOI: 10.1038/s41380-021-01385-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/16/2021] [Accepted: 10/27/2021] [Indexed: 12/21/2022]
Abstract
One of the hallmarks of Alzheimer's disease (AD) are deposits of amyloid-beta (Aβ) protein in amyloid plaques in the brain. The Aβ peptide exists in several forms, including full-length Aβ1-42 and Aβ1-40 - and the N-truncated species, pyroglutamate Aβ3-42 and Aβ4-42, which appear to play a major role in neurodegeneration. We previously identified a murine antibody (TAP01), which binds specifically to soluble, non-plaque N-truncated Aβ species. By solving crystal structures for TAP01 family antibodies bound to pyroglutamate Aβ3-14, we identified a novel pseudo β-hairpin structure in the N-terminal region of Aβ and show that this underpins its unique binding properties. We engineered a stabilised cyclic form of Aβ1-14 (N-Truncated Amyloid Peptide AntibodieS; the 'TAPAS' vaccine) and showed that this adopts the same 3-dimensional conformation as the native sequence when bound to TAP01. Active immunisation of two mouse models of AD with the TAPAS vaccine led to a striking reduction in amyloid-plaque formation, a rescue of brain glucose metabolism, a stabilisation in neuron loss, and a rescue of memory deficiencies. Treating both models with the humanised version of the TAP01 antibody had similar positive effects. Here we report the discovery of a unique conformational epitope in the N-terminal region of Aβ, which offers new routes for active and passive immunisation against AD.
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Pyroglutamate Aβ cascade as drug target in Alzheimer's disease. Mol Psychiatry 2022; 27:1880-1885. [PMID: 34880449 PMCID: PMC9126800 DOI: 10.1038/s41380-021-01409-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 02/07/2023]
Abstract
One of the central aims in Alzheimer's disease (AD) research is the identification of clinically relevant drug targets. A plethora of potential molecular targets work very well in preclinical model systems both in vitro and in vivo in AD mouse models. However, the lack of translation into clinical settings in the AD field is a challenging endeavor. Although it is long known that N-terminally truncated and pyroglutamate-modified Abeta (AβpE3) peptides are abundantly present in the brain of AD patients, form stable and soluble low-molecular weight oligomers, and induce neurodegeneration in AD mouse models, their potential as drug target has not been generally accepted in the past. This situation has dramatically changed with the report that passive immunization with donanemab, an AβpE3-specific antibody, cleared aymloid plaques and stabilized cognitive deficits in a group of patients with mild AD in a phase II trial. This review summarizes the current knowledge on the molecular mechanisms of generation of AβpE, its biochemical properties, and the intervention points as a drug target in AD.
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Long-term caffeine treatment of Alzheimer mouse models ameliorates behavioural deficits and neuron loss and promotes cellular and molecular markers of neurogenesis. Cell Mol Life Sci 2021; 79:55. [PMID: 34913091 PMCID: PMC8738505 DOI: 10.1007/s00018-021-04062-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/15/2021] [Accepted: 11/24/2021] [Indexed: 01/04/2023]
Abstract
Epidemiological studies indicate that the consumption of caffeine, the most commonly ingested psychoactive substance found in coffee, tea or soft drinks, reduces the risk of developing Alzheimer’s disease (AD). Previous treatment studies with transgenic AD mouse models reported a reduced amyloid plaque load and an amelioration of behavioral deficits. It has been further shown that moderate doses of caffeine have the potential to attenuate the health burden in preclinical mouse models of a variety of brain disorders (reviewed in Cunha in J Neurochem 139:1019–1055, 2016). In the current study, we assessed whether long-term caffeine consumption affected hippocampal neuron loss and associated behavioral deficits in the Tg4-42 mouse model of AD. Treatment over a 4-month period reduced hippocampal neuron loss, rescued learning and memory deficits, and ameliorated impaired neurogenesis. Neuron-specific RNA sequencing analysis in the hippocampus revealed an altered expression profile distinguished by the up-regulation of genes linked to synaptic function and processes, and to neural progenitor proliferation. Treatment of 5xFAD mice, which develop prominent amyloid pathology, with the same paradigm also rescued behavioral deficits but did not affect extracellular amyloid-β (Aβ) levels or amyloid precursor protein (APP) processing. These findings challenge previous assumptions that caffeine is anti-amyloidogenic and indicate that the promotion of neurogenesis might play a role in its beneficial effects.
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Bayer TA. N-Truncated Aβ Starting at Position Four-Biochemical Features, Preclinical Models, and Potential as Drug Target in Alzheimer's Disease. Front Aging Neurosci 2021; 13:710579. [PMID: 34489680 PMCID: PMC8417877 DOI: 10.3389/fnagi.2021.710579] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 07/29/2021] [Indexed: 12/21/2022] Open
Abstract
The discussion of whether amyloid plaque Aβ is a valid drug target to fight Alzheimer’s disease (AD) has been a matter of scientific dispute for decades. This question can only be settled by successful clinical trials and the approval of disease-modifying drugs. However, many clinical trials with antibodies against different regions of the amyloid Aβ peptide have been discontinued, as they did not meet the clinical endpoints required. Recently, passive immunization of AD patients with Donanemab, an antibody directed against the N-terminus of pyroglutamate Aβ, showed beneficial effects in a phase II trial, supporting the concept that N-truncated Aβ is a relevant target for AD therapy. There is long-standing evidence that N-truncated Aβ variants are the main variants found in amyloid plaques besides full-length Aβ1–42, t, therefore their role in triggering AD pathology and as targets for drug development are of interest. While the contribution of pyroglutamate Aβ3–42 to AD pathology has been well studied in the past, the potential role of Aβ4–42 has been largely neglected. The present review will therefore focus on Aβ4–42 as a possible drug target based on human and mouse pathology, in vitro and in vivo toxicity, and anti-Aβ4-X therapeutic effects in preclinical models.
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Affiliation(s)
- Thomas A Bayer
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
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Zampar S, Wirths O. Characterization of a Mouse Model of Alzheimer's Disease Expressing Aβ4-42 and Human Mutant Tau. Int J Mol Sci 2021; 22:ijms22105191. [PMID: 34069029 PMCID: PMC8156793 DOI: 10.3390/ijms22105191] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 01/04/2023] Open
Abstract
The relationship between the two most prominent neuropathological hallmarks of Alzheimer’s Disease (AD), extracellular amyloid-β (Aβ) deposits and intracellular accumulation of hyperphosphorylated tau in neurofibrillary tangles (NFT), remains at present not fully understood. A large body of evidence places Aβ upstream in the cascade of pathological events, triggering NFTs formation and the subsequent neuron loss. Extracellular Aβ deposits were indeed causative of an increased tau phosphorylation and accumulation in several transgenic models but the contribution of soluble Aβ peptides is still controversial. Among the different Aβ variants, the N-terminally truncated peptide Aβ4–42 is among the most abundant. To understand whether soluble Aβ4–42 peptides impact the onset or extent of tau pathology, we have crossed the homozygous Tg4–42 mouse model of AD, exclusively expressing Aβ4–42 peptides, with the PS19 (P301S) tau transgenic model. Behavioral assessment showed that the resulting double-transgenic line presented a partial worsening of motor performance and spatial memory deficits in the aged group. While an increased loss of distal CA1 pyramidal neurons was detected in young mice, no significant alterations in hippocampal tau phosphorylation were observed in immunohistochemical analyses.
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Sun ZT, Ma C, Li GJ, Zheng XY, Hao YT, Yang Y, Wang X. Application of Antibody Fragments Against Aβ With Emphasis on Combined Application With Nanoparticles in Alzheimer's Disease. Front Pharmacol 2021; 12:654611. [PMID: 33967797 PMCID: PMC8100690 DOI: 10.3389/fphar.2021.654611] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 04/09/2021] [Indexed: 11/13/2022] Open
Abstract
Alzheimer’s disease (AD) is one of the most common neurodegenerative diseases and accumulating evidences suggest a key role of amyloid-β (Aβ) peptide in the pathogenesis of AD. According to the amyloid cascade hypothesis, the imbalance of producing and clearing Aβ is the beginning of neurodegeneration and dementia. Consequently, immunotherapy becomes popular through using antibodies against Aβ. However, many studies of monoclonal antibodies were stopped because adverse effects appeared or there were no evident benefits observed. Some antibody fragments have many advantages over monoclonal antibodies, such as small sizes, lack of the crystallizable fraction (Fc) and so on. There are three main antibody fragments, including single chain variable fragments (scFvs), Fab fragments and single-domain antibody fragments. Nanoparticles can facilitate the entry of drug molecules across the blood-brain barrier, making them become excellent carriers. Various kinds of nanoparticles have been applied in the treatment of AD. The combination of nanoparticles and antibody fragments against amyloid-β can be used in the diagnosis and treatment of Alzheimer’s disease. In this review, we summarize the progress of antibody fragments against amyloid-β in AD, focusing on the combined application with nanoparticles in the diagnosis and treatment of AD.
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Affiliation(s)
- Zhi-Ting Sun
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Chi Ma
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China
| | - Guang-Jian Li
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Xiang-Yu Zheng
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Yi-Tong Hao
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Yu Yang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Xu Wang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
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Hinteregger B, Loeffler T, Flunkert S, Neddens J, Bayer TA, Madl T, Hutter-Paier B. Metabolic, Phenotypic, and Neuropathological Characterization of the Tg4-42 Mouse Model for Alzheimer's Disease. J Alzheimers Dis 2021; 80:1151-1168. [PMID: 33646155 PMCID: PMC8150512 DOI: 10.3233/jad-201204] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND Preclinical Alzheimer's disease (AD) research strongly depends on transgenic mouse models that display major symptoms of the disease. Although several AD mouse models have been developed representing relevant pathologies, only a fraction of available mouse models, like the Tg4-42 mouse model, display hippocampal atrophy caused by the death of neurons as the key feature of AD. The Tg4-42 mouse model is therefore very valuable for use in preclinical research. Furthermore, metabolic biomarkers which have the potential to detect biochemical changes, are crucial to gain deeper insights into the pathways, the underlying pathological mechanisms and disease progression. OBJECTIVE We thus performed an in-depth characterization of Tg4-42 mice by using an integrated approach to analyze alterations of complex biological networks in this AD in vivo model. METHODS Therefore, untargeted NMR-based metabolomic phenotyping was combined with behavioral tests and immunohistological and biochemical analyses. RESULTS Our in vivo experiments demonstrate a loss of body weight increase in homozygous Tg4-42 mice over time as well as severe impaired learning behavior and memory deficits in the Morris water maze behavioral test. Furthermore, we found significantly altered metabolites in two different brain regions and metabolic changes of the glutamate/4-aminobutyrate-glutamine axis. Based on these results, downstream effects were analyzed showing increased Aβ42 levels, increased neuroinflammation as indicated by increased astro- and microgliosis as well as neuronal degeneration and neuronal loss in homozygous Tg4-42 mice. CONCLUSION Our study provides a comprehensive characterization of the Tg4-42 mouse model which could lead to a deeper understanding of pathological features of AD. Additionally this study reveals changes in metabolic biomarker which set the base for future preclinical studies or drug development.
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Affiliation(s)
- Barbara Hinteregger
- QPS Austria GmbH, Grambach, Austria
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging), Division of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | | | | | | | - Thomas A. Bayer
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, University Medical Center, Göttingen (UMG), Göttingen, Germany
| | - Tobias Madl
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging), Division of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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Stazi M, Wirths O. Physical activity and cognitive stimulation ameliorate learning and motor deficits in a transgenic mouse model of Alzheimer's disease. Behav Brain Res 2020; 397:112951. [PMID: 33027669 DOI: 10.1016/j.bbr.2020.112951] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/07/2020] [Accepted: 09/26/2020] [Indexed: 10/23/2022]
Abstract
Epidemiological studies suggest that physical exercise or cognitive stimulation might contribute to lower the risk of developing dementia disorders such as Alzheimer's disease (AD). Here, we used the well-established enrichment environment (EE) paradigm to study the impact of prolonged physical activity and cognitive stimulation in a mouse model of AD overexpressing only Aβ4-42 peptides. These mice display age-dependent memory and motor deficits, in the absence of human amyloid precursor protein (APP) overexpression. We demonstrate that housing under EE conditions leads to an entire preservation of recognition and spatial memory, as well as a rescue of motor deficits in this mouse model. Moreover, we find that Tg4-42hom mice present a typical floating phenotype in the Morris water maze task that could be completely ameliorated upon long-term EE housing. Our findings are in line with epidemiological studies suggesting that physical activity and cognitive stimulation might represent efficient strategies to prevent age-related neurodegenerative disorders such as AD.
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Affiliation(s)
- Martina Stazi
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany.
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Stazi M, Wirths O. Chronic Memantine Treatment Ameliorates Behavioral Deficits, Neuron Loss, and Impaired Neurogenesis in a Model of Alzheimer's Disease. Mol Neurobiol 2020; 58:204-216. [PMID: 32914393 PMCID: PMC7695672 DOI: 10.1007/s12035-020-02120-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 09/05/2020] [Indexed: 02/06/2023]
Abstract
Memantine, a non-competitive NMDA receptor antagonist possessing neuroprotective properties, belongs to the small group of drugs which have been approved for the treatment of Alzheimer's disease (AD). While several preclinical studies employing different transgenic AD mouse models have described beneficial effects with regard to rescued behavioral deficits or reduced amyloid plaque pathology, it is largely unknown whether memantine might have beneficial effects on neurodegeneration. In the current study, we assessed whether memantine treatment has an impact on hippocampal neuron loss and associated behavioral deficits in the Tg4-42 mouse model of AD. We demonstrate that a chronic oral memantine treatment for 4 months diminishes hippocampal CA1 neuron loss and rescues learning and memory performance in different behavioral paradigms, such as Morris water maze or a novel object recognition task. Cognitive benefits of chronic memantine treatment were accompanied by an amelioration of impaired adult hippocampal neurogenesis. Taken together, our results demonstrate that memantine successfully counteracts pathological alterations in a preclinical mouse model of AD.
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Affiliation(s)
- Martina Stazi
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August University, Von-Siebold-Str. 5, 37075, Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August University, Von-Siebold-Str. 5, 37075, Göttingen, Germany.
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Pinheiro L, Faustino C. Therapeutic Strategies Targeting Amyloid-β in Alzheimer's Disease. Curr Alzheimer Res 2020; 16:418-452. [PMID: 30907320 DOI: 10.2174/1567205016666190321163438] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/16/2019] [Accepted: 03/17/2019] [Indexed: 12/16/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder linked to protein misfolding and aggregation. AD is pathologically characterized by senile plaques formed by extracellular Amyloid-β (Aβ) peptide and Intracellular Neurofibrillary Tangles (NFT) formed by hyperphosphorylated tau protein. Extensive synaptic loss and neuronal degeneration are responsible for memory impairment, cognitive decline and behavioral dysfunctions typical of AD. Amyloidosis has been implicated in the depression of acetylcholine synthesis and release, overactivation of N-methyl-D-aspartate (NMDA) receptors and increased intracellular calcium levels that result in excitotoxic neuronal degeneration. Current drugs used in AD treatment are either cholinesterase inhibitors or NMDA receptor antagonists; however, they provide only symptomatic relief and do not alter the progression of the disease. Aβ is the product of Amyloid Precursor Protein (APP) processing after successive cleavage by β- and γ-secretases while APP proteolysis by α-secretase results in non-amyloidogenic products. According to the amyloid cascade hypothesis, Aβ dyshomeostasis results in the accumulation and aggregation of Aβ into soluble oligomers and insoluble fibrils. The former are synaptotoxic and can induce tau hyperphosphorylation while the latter deposit in senile plaques and elicit proinflammatory responses, contributing to oxidative stress, neuronal degeneration and neuroinflammation. Aβ-protein-targeted therapeutic strategies are thus a promising disease-modifying approach for the treatment and prevention of AD. This review summarizes recent findings on Aβ-protein targeted AD drugs, including β-secretase inhibitors, γ-secretase inhibitors and modulators, α-secretase activators, direct inhibitors of Aβ aggregation and immunotherapy targeting Aβ, focusing mainly on those currently under clinical trials.
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Affiliation(s)
- Lídia Pinheiro
- iMed.ULisboa - Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto 1649-003 Lisboa, Portugal
| | - Célia Faustino
- iMed.ULisboa - Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto 1649-003 Lisboa, Portugal
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14
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Gerberding AL, Zampar S, Stazi M, Liebetanz D, Wirths O. Physical Activity Ameliorates Impaired Hippocampal Neurogenesis in the Tg4-42 Mouse Model of Alzheimer's Disease. ASN Neuro 2020; 11:1759091419892692. [PMID: 31818124 PMCID: PMC6906584 DOI: 10.1177/1759091419892692] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
There is growing evidence from epidemiological studies that especially midlife physical activity might exert a positive influence on the risk and progression of Alzheimer’s disease. In this study, the Tg4-42 mouse model of Alzheimer’s disease has been utilized to assess the effect of different housing conditions on structural changes in the hippocampus. Focusing on the dentate gyrus, we demonstrate that 6-month-old Tg4-42 mice have a reduced number of newborn neurons in comparison to age-matched wild-type mice. Housing these mice for 4 months with either unlimited or intermittent access to a running wheel resulted in a significant rescue of dentate gyrus neurogenesis. Although neither dentate gyrus volume nor neuron number could be modified in this Alzheimer’s disease mouse model, unrestricted access to a running wheel significantly increased dentate gyrus volume and granule cell number in wild-type mice.
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Affiliation(s)
- Anna-Lina Gerberding
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Silvia Zampar
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Martina Stazi
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - David Liebetanz
- Department of Clinical Neurophysiology, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
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15
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Hinteregger B, Loeffler T, Flunkert S, Neddens J, Birner-Gruenberger R, Bayer TA, Madl T, Hutter-Paier B. Transgene integration causes RARB downregulation in homozygous Tg4-42 mice. Sci Rep 2020; 10:6377. [PMID: 32286473 PMCID: PMC7156671 DOI: 10.1038/s41598-020-63512-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 03/30/2020] [Indexed: 02/07/2023] Open
Abstract
Alzheimer's disease can be modelled by different transgenic mouse strains. To gain deeper insight into disease model mechanisms, the previously described Tg4-42 mouse was analysed for transgene integration. On RNA/DNA level the transgene integration resulted in more than 20 copy numbers and further caused a deletion of exon 2 of the retinoic acid receptor beta. These findings were also confirmed on protein level with highly decreased retinoic acid receptor beta protein levels in homozygous Tg4-42 mice and may have an impact on the previously described phenotype of homozygous Tg4-42 mice to be solely dependent on amyloid-ß 4-42 expression. Since hemizygous mice show no changes in RARB protein levels it can be concluded that the previously described phenotype of these mice should not be affected by the retinoic acid receptor beta gene knockout. In order to fully understand the results of transgenesis, it is extremely advisable to determine the genome integration site and the basic structure of the inserted transgenes. This can be carried out for instance by next-generation sequencing techniques. Our results thus suggest that a detailed characterization of new disease models using the latest genomics technologies prior to functional studies could be a valuable tool to avoid an unexpected genetic influence on the animals' phenotype that is not only based on the inserted transgene. This would also significantly improve the selection of mouse models that are best suited for therapeutic development and basic research.
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Affiliation(s)
- Barbara Hinteregger
- QPS Austria GmbH, Parkring 12, 8074, Grambach, Austria
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging) Division of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Tina Loeffler
- QPS Austria GmbH, Parkring 12, 8074, Grambach, Austria
| | | | - Joerg Neddens
- QPS Austria GmbH, Parkring 12, 8074, Grambach, Austria
| | - Ruth Birner-Gruenberger
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging) Division of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- Diagnostic and Research Institute of Pathology & Omics Center Graz, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
- Vienna University of Technology, Institute of Chemical Technologies and Analytics, Vienna, Austria
| | - Thomas A Bayer
- Department of Psychiatry and Psychotherapy, Division of Molecular Psychiatry, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Tobias Madl
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging) Division of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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16
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Acero G, Garay C, Venegas D, Ortega E, Gevorkian G. Novel monoclonal antibody 3B8 specifically recognizes pyroglutamate-modified amyloid β 3-42 peptide in brain of AD patients and 3xTg-AD transgenic mice. Neurosci Lett 2020; 724:134876. [PMID: 32114116 DOI: 10.1016/j.neulet.2020.134876] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/11/2020] [Accepted: 02/26/2020] [Indexed: 12/19/2022]
Abstract
In addition to the full-length beta-amyloid peptides (Aβ 1-40/42), several Aβ variants, truncated at their N- or C-termini and bearing different post-translational modifications, have been detected in the brain of Alzheimer´s disease (AD) patients. AβN3(pE), an Aβ peptide bearing an amino-terminal pyroglutamate at position 3, is a significant constituent of intracellular, extracellular and vascular Aβ deposits in brain tissue from individuals with AD and Down syndrome. Pioneering immunotherapy studies have primarily focused on the full-length Aβ peptide, disregarding the presence of N-truncated/modified species. However, in recent years, increasing attention has been directed towards AβN3(pE), in both pre-clinical studies and clinical trials. In the present study, we generated and characterized an anti-AβN3(pE) mouse monoclonal antibody (3B8) that recognizes amyloid aggregates in brain tissue from AD patients and in 3xTg-AD transgenic mice. To identify the epitope recognized by 3B8, a library of random heptapeptides fused to the minor coat protein of M13 phage was screened. Results from screening, along with those from ELISA assays against distinct Aβ fragments, suggest recognition of two conformational epitopes present in AβN3(pE) and Aβ 3-42, regardless of the glutamate-pyroglutamate modification. The novel 3B8 antibody may be useful in future therapeutic and diagnostic applications for AD.
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Affiliation(s)
- Gonzalo Acero
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70228, Cuidad Universitaria, CDMX, CP, 04510, Mexico
| | - Claudia Garay
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70228, Cuidad Universitaria, CDMX, CP, 04510, Mexico
| | - David Venegas
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70228, Cuidad Universitaria, CDMX, CP, 04510, Mexico
| | - Enrique Ortega
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70228, Cuidad Universitaria, CDMX, CP, 04510, Mexico
| | - Goar Gevorkian
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70228, Cuidad Universitaria, CDMX, CP, 04510, Mexico.
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17
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Wagner JM, Sichler ME, Schleicher EM, Franke TN, Irwin C, Löw MJ, Beindorff N, Bouter C, Bayer TA, Bouter Y. Analysis of Motor Function in the Tg4-42 Mouse Model of Alzheimer's Disease. Front Behav Neurosci 2019; 13:107. [PMID: 31156407 PMCID: PMC6533559 DOI: 10.3389/fnbeh.2019.00107] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 05/02/2019] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder and the most common form of dementia. Hallmarks of AD are memory impairments and cognitive deficits, but non-cognitive impairments, especially motor dysfunctions are also associated with the disease and may even precede classic clinical symptoms. With an aging society and increasing hospitalization of the elderly, motor deficits are of major interest to improve independent activities in daily living. Consistent with clinical findings, a variety of AD mouse models develop motor deficits as well. We investigated the motor function of 3- and 7-month-old Tg4-42 mice in comparison to wild-type controls and 5XFAD mice and discuss the results in context with several other AD mouse model. Our study shows impaired balance and motor coordination in aged Tg4-42 mice in the balance beam and rotarod test, while general locomotor activity and muscle strength is not impaired at 7 months. The cerebellum is a major player in the regulation and coordination of balance and locomotion through practice. Particularly, the rotarod test is able to detect cerebellar deficits. Furthermore, supposed cerebellar impairment was verified by 18F-FDG PET/MRI. Aged Tg4-42 mice showed reduced cerebellar glucose metabolism in the 18F-FDG PET. Suggesting that, deficits in coordination and balance are most likely due to cerebellar impairment. In conclusion, Tg4-42 mice develop motor deficits before memory deficits, without confounding memory test. Thus, making the Tg4-42 mouse model a good model to study the effects on cognitive decline of therapies targeting motor impairments.
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Affiliation(s)
- Jannek M Wagner
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Marius E Sichler
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Eva M Schleicher
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Timon N Franke
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Caroline Irwin
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Maximilian Johannes Löw
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Nicola Beindorff
- Berlin Experimental Radionuclide Imaging Center, Charité - University Medicine Berlin, Berlin, Germany
| | - Caroline Bouter
- Department of Nuclear Medicine, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Thomas A Bayer
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Yvonne Bouter
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
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18
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Bouter C, Bouter Y. 18F-FDG-PET in Mouse Models of Alzheimer's Disease. Front Med (Lausanne) 2019; 6:71. [PMID: 31058151 PMCID: PMC6482246 DOI: 10.3389/fmed.2019.00071] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 03/21/2019] [Indexed: 01/08/2023] Open
Abstract
Suitable animal models and in vivo biomarkers are essential for development and evaluation of new therapeutic strategies in Alzheimer's disease (AD). 18F-Fluorodeoxyglucose (18F-FDG)-positron-emission tomography (PET) is an imaging biomarker that allows the assessment of cerebral glucose metabolism in vivo. While 18F-FDG-PET/CT is an established tool in the evaluation of AD patients, its role in preclinical studies with AD mouse models remains unclear. Here, we want to review available studies on 18F-FDG-PET/CT in AD mouse models in order to evaluate the method and its impact in preclinical AD research. Only a limited number of studies using 18F-FDG-PET in AD mice were carried out so far showing contradictory findings in cerebral FDG uptake. Methodological differences as well as underlying pathological features of used mouse models seem to be accountable for those varying results. However, 18F-FDG-PET can be a valuable tool in longitudinal in vivo therapy monitoring with a lot of potential for future studies.
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Affiliation(s)
- Caroline Bouter
- Department of Nuclear Medicine, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - Yvonne Bouter
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
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19
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Bouter C, Henniges P, Franke TN, Irwin C, Sahlmann CO, Sichler ME, Beindorff N, Bayer TA, Bouter Y. 18F-FDG-PET Detects Drastic Changes in Brain Metabolism in the Tg4-42 Model of Alzheimer's Disease. Front Aging Neurosci 2019; 10:425. [PMID: 30670962 PMCID: PMC6333025 DOI: 10.3389/fnagi.2018.00425] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/07/2018] [Indexed: 12/19/2022] Open
Abstract
The evaluation of new therapeutic strategies in Alzheimer’s disease (AD) relies heavily on in vivo imaging and suitable animal models that mimic the pathological changes seen in patients. 18F-Fluorodeoxyglucose (18F-FDG)-positron-emission tomography (PET) is a well-established non-invasive imaging tool for monitoring changes in cerebral brain glucose metabolism in vivo. 18F-FDG-PET is used as a functional biomarker for AD as patients show an early and progressive reduction of cerebral glucose metabolism. However, earlier studies in preclinical models of AD showed conflicting results. The aim of this study was the evaluation of cerebral glucose metabolism in the Tg4–42 mouse model of AD using 18F-FDG-PET/magnetic resonance imaging (MRI). Tg4–42 mice show an age-dependent reduction in glucose metabolism together with severe neuron loss and memory deficits. Similar to AD patients early decrease in 18F-FDG uptake was already detected in young (3 months) Tg4–42 mice. The altered glucose metabolism coupled with age- and disease related cognitive decline of Tg4–42 mice make it a well-suited model for preclinical testing of AD-relevant therapeutics.
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Affiliation(s)
- Caroline Bouter
- Department of Nuclear Medicine, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Philipp Henniges
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Timon N Franke
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Caroline Irwin
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Carsten Oliver Sahlmann
- Department of Nuclear Medicine, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Marius E Sichler
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Nicola Beindorff
- Berlin Experimental Radionuclide Imaging Center (BERIC), Charité-University Medicine Berlin, Berlin, Germany
| | - Thomas A Bayer
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Yvonne Bouter
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
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20
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Zhang Y, Huai Y, Zhang X, Song C, Cai J, Zhang Y. The Mode of Action of an Anti-Oligomeric Amyloid β-Protein Antibody Affects its Protective Efficacy. Neurotox Res 2018; 35:304-317. [PMID: 30229545 DOI: 10.1007/s12640-018-9955-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 09/06/2018] [Accepted: 09/07/2018] [Indexed: 12/22/2022]
Abstract
The process of developing antibody drugs for Alzheimer's disease therapy has been both long and difficult; however, recent advances suggest that antibodies against neurotoxic Αβ42 can suppress the progression of AD, especially on its early stage. Here, we obtained and characterized a novel anti-oligomeric Aβ42 aggregate scFv antibody, HT7, which could induce the significant disaggregation of Aβ42 aggregates through the release of stable and non-cytotoxic hexameric complexes that were composed of three scFv HT7s and one Aβ42 trimer, the latter being found to serve as the assembled subunit within larger Aβ42 aggregates in addition to existing freely between the cells. The docking model of the scFv HT7-Aβ42 complex revealed that only the N-terminal peptide of the Aβ42 molecule was bound into the groove between the VH and VL domains of scFv HT7. Thus, it was suggested that the hydrophobic interaction between the C-terminal peptides of Aβ42 molecules maintained the stability of the Aβ42 trimers or the Aβ42 trimer subunits. The saturation of Aβ42 trimer subunits by scFv HT7 and the subsequent dissociation of the scFv HT7-saturated Aβ42 trimer subunits from larger Aβ42 aggregates constituted the primary mechanisms underlying the high efficacy of scFv HT7. Our findings revealed that it was not sufficient for an anti-oligomeric Aβ42 antibody to exhibit high specificity and high affinity to the oligomeric Aβ42 aggregates in order to promote Aβ42 aggregate clearance and neutralize their cytotoxic effects. Here, for the first time, we proposed a "post-saturation dissociation" mechanism of Aβ42 oligomeric subunits for effective anti-Aβ42 antibodies.
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Affiliation(s)
- Yunlong Zhang
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, 2699 Qian-Jin Street, Changchun, 130012, Jilin, China
| | - Yangyang Huai
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, 2699 Qian-Jin Street, Changchun, 130012, Jilin, China
| | - Xiaoning Zhang
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, 2699 Qian-Jin Street, Changchun, 130012, Jilin, China
| | - Chuli Song
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, 2699 Qian-Jin Street, Changchun, 130012, Jilin, China
| | - Jing Cai
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, 2699 Qian-Jin Street, Changchun, 130012, Jilin, China.,China-Japan Union Hospital of Jilin University, Changchun, China
| | - Yingjiu Zhang
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, 2699 Qian-Jin Street, Changchun, 130012, Jilin, China. .,School of Life Science, Jilin University, Changchun, China.
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21
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Dunys J, Valverde A, Checler F. Are N- and C-terminally truncated Aβ species key pathological triggers in Alzheimer's disease? J Biol Chem 2018; 293:15419-15428. [PMID: 30143530 DOI: 10.1074/jbc.r118.003999] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The histopathology of Alzheimer's disease (AD) is characterized by neuronal loss, neurofibrillary tangles, and senile plaque formation. The latter results from an exacerbated production (familial AD cases) or altered degradation (sporadic cases) of 40/42-amino acid-long β-amyloid peptides (Aβ peptides) that are produced by sequential cleavages of Aβ precursor protein (βAPP) by β- and γ-secretases. The amyloid cascade hypothesis proposes a key role for the full-length Aβ42 and the Aβ40/42 ratio in AD etiology, in which soluble Aβ oligomers lead to neurotoxicity, tau hyperphosphorylation, aggregation, and, ultimately, cognitive defects. However, following this postulate, during the last decade, several clinical approaches aimed at decreasing full-length Aβ42 production or neutralizing it by immunotherapy have failed to reduce or even stabilize AD-related decline. Thus, the Aβ peptide (Aβ40/42)-centric hypothesis is probably a simplified view of a much more complex situation involving a multiplicity of APP fragments and Aβ catabolites. Indeed, biochemical analyses of AD brain deposits and fluids have unraveled an Aβ peptidome consisting of additional Aβ-related species. Such Aβ catabolites could be due to either primary enzymatic cleavages of βAPP or secondary processing of Aβ itself by exopeptidases. Here, we review the diversity of N- and C-terminally truncated Aβ peptides and their biosynthesis and outline their potential function/toxicity. We also highlight their potential as new pharmaceutical targets and biomarkers.
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Affiliation(s)
- Julie Dunys
- From the Université Côte d'Azur, INSERM, CNRS, IPMC, Team labeled "Laboratory of Excellence (LABEX) Distalz," 660 Route des Lucioles, Sophia-Antipolis, 06560 Valbonne, France
| | - Audrey Valverde
- From the Université Côte d'Azur, INSERM, CNRS, IPMC, Team labeled "Laboratory of Excellence (LABEX) Distalz," 660 Route des Lucioles, Sophia-Antipolis, 06560 Valbonne, France
| | - Frédéric Checler
- From the Université Côte d'Azur, INSERM, CNRS, IPMC, Team labeled "Laboratory of Excellence (LABEX) Distalz," 660 Route des Lucioles, Sophia-Antipolis, 06560 Valbonne, France
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22
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Li G, Yang WY, Zhao YF, Chen YX, Hong L, Li YM. Differential Modulation of the Aggregation of N-Terminal Truncated Aβ using Cucurbiturils. Chemistry 2018; 24:13647-13653. [DOI: 10.1002/chem.201802655] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Gao Li
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry; Tsinghua University; 100084 Beijing China
| | - Wu-Yue Yang
- Zhou Pei-Yuan Center for Applied Mathematics; Department of, Mathematical Sciences; Tsinghua University; 100084 Beijing China
| | - Yu-Fen Zhao
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry; Tsinghua University; 100084 Beijing China
| | - Yong-Xiang Chen
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry; Tsinghua University; 100084 Beijing China
| | - Liu Hong
- Zhou Pei-Yuan Center for Applied Mathematics; Department of, Mathematical Sciences; Tsinghua University; 100084 Beijing China
| | - Yan-Mei Li
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry; Tsinghua University; 100084 Beijing China
- Beijing Institute for Brain Disorders; 100069 Beijing China
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23
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PTK2B/Pyk2 overexpression improves a mouse model of Alzheimer's disease. Exp Neurol 2018; 307:62-73. [PMID: 29803828 DOI: 10.1016/j.expneurol.2018.05.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/14/2018] [Accepted: 05/23/2018] [Indexed: 12/31/2022]
Abstract
Pyk2 is a Ca2+-activated non-receptor tyrosine kinase enriched in forebrain neurons and involved in synaptic regulation. Human genetic studies associated PTK2B, the gene coding Pyk2, with risk for Alzheimer's disease (AD). We previously showed that Pyk2 is important for hippocampal function, plasticity, and spine structure. However, its potential role in AD is unknown. To address this question we used human brain samples and 5XFAD mice, an amyloid mouse model of AD expressing mutated human amyloid precursor protein and presenilin1. In the hippocampus of 5XFAD mice and in human AD patients' cortex and hippocampus, Pyk2 total levels were normal. However, Pyk2 Tyr-402 phosphorylation levels, reflecting its autophosphorylation-dependent activity, were reduced in 5XFAD mice at 8 months of age but not 3 months. We crossed these mice with Pyk2-/- mice to generate 5XFAD animals devoid of Pyk2. At 8 months the phenotype of 5XFAD x Pyk2-/- double mutant mice was not different from that of 5XFAD. In contrast, overexpression of Pyk2 in the hippocampus of 5XFAD mice, using adeno-associated virus, rescued autophosphorylated Pyk2 levels and improved synaptic markers and performance in several behavioral tasks. Both Pyk2-/- and 5XFAD mice showed an increase of potentially neurotoxic Src cleavage product, which was rescued by Pyk2 overexpression. Manipulating Pyk2 levels had only minor effects on Aβ plaques, which were slightly decreased in hippocampus CA3 region of double mutant mice and increased following overexpression. Our results show that Pyk2 is not essential for the pathogenic effects of human amyloidogenic mutations in the 5XFAD mouse model. However, the slight decrease in plaque number observed in these mice in the absence of Pyk2 and their increase following Pyk2 overexpression suggest a contribution of this kinase in plaque formation. Importantly, a decreased function of Pyk2 was observed in 5XFAD mice, indicated by its decreased autophosphorylation and associated Src alterations. Overcoming this deficit by Pyk2 overexpression improved the behavioral and molecular phenotype of 5XFAD mice. Thus, our results in a mouse model of AD suggest that Pyk2 impairment may play a role in the symptoms of the disease.
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24
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Sumner IL, Edwards RA, Asuni AA, Teeling JL. Antibody Engineering for Optimized Immunotherapy in Alzheimer's Disease. Front Neurosci 2018; 12:254. [PMID: 29740272 PMCID: PMC5924811 DOI: 10.3389/fnins.2018.00254] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/03/2018] [Indexed: 12/17/2022] Open
Abstract
There are nearly 50 million people with Alzheimer's disease (AD) worldwide and currently no disease modifying treatment is available. AD is characterized by deposits of Amyloid-β (Aβ), neurofibrillary tangles, and neuroinflammation, and several drug discovery programmes studies have focussed on Aβ as therapeutic target. Active immunization and passive immunization against Aβ leads to the clearance of deposits in humans and transgenic mice expressing human Aβ but have failed to improve memory loss. This review will discuss the possible explanations for the lack of efficacy of Aβ immunotherapy, including the role of a pro-inflammatory response and subsequent vascular side effects, the binding site of therapeutic antibodies and the timing of the treatment. We further discuss how antibodies can be engineered for improved efficacy.
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Affiliation(s)
- Isabelle L Sumner
- Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Ross A Edwards
- Biological Sciences, University of Southampton, Southampton, United Kingdom
| | | | - Jessica L Teeling
- Biological Sciences, University of Southampton, Southampton, United Kingdom
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25
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Mehta PD, Patrick BA, Barshatzky M, Mehta SP, Frackowiak J, Mazur-Kolecka B, Wegiel J, Wisniewski T, Miller DL. Generation and Partial Characterization of Rabbit Monoclonal Antibody to Pyroglutamate Amyloid-β3-42 (pE3-Aβ). J Alzheimers Dis 2018; 62:1635-1649. [DOI: 10.3233/jad-170898] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Pankaj D. Mehta
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Bruce A. Patrick
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Marc Barshatzky
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Sangita P. Mehta
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Janusz Frackowiak
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Bozena Mazur-Kolecka
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Jerzy Wegiel
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Thomas Wisniewski
- Center for Cognitive Neurology, New York University School of Medicine, New York, NY, USA
| | - David L. Miller
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
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26
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Dietrich K, Bouter Y, Müller M, Bayer TA. Synaptic Alterations in Mouse Models for Alzheimer Disease-A Special Focus on N-Truncated Abeta 4-42. Molecules 2018; 23:E718. [PMID: 29561816 PMCID: PMC6017701 DOI: 10.3390/molecules23040718] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 03/16/2018] [Accepted: 03/19/2018] [Indexed: 11/29/2022] Open
Abstract
This commentary reviews the role of the Alzheimer amyloid peptide Aβ on basal synaptic transmission, synaptic short-term plasticity, as well as short- and long-term potentiation in transgenic mice, with a special focus on N-terminal truncated Aβ4-42. Aβ4-42 is highly abundant in the brain of Alzheimer's disease (AD) patients. It demonstrates increased neurotoxicity compared to full length Aβ, suggesting an important role in the pathogenesis of AD. Transgenic Tg4-42 mice, a model for sporadic AD, express human Aβ4-42 in Cornu Ammonis (CA1) neurons, and develop age-dependent hippocampal neuron loss and neurological deficits. In contrast to other transgenic AD mouse models, the Tg4-42 model exhibits synaptic hyperexcitability, altered synaptic short-term plasticity with no alterations in short- and long-term potentiation. The outcomes of this study are discussed in comparison with controversial results from other AD mouse models.
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Affiliation(s)
- Katharina Dietrich
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, von-Siebold-Strasse 5, 37075 Göttingen, Germany.
| | - Yvonne Bouter
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, von-Siebold-Strasse 5, 37075 Göttingen, Germany.
| | - Michael Müller
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Humboldtallee 23, 37073 Göttingen, Germany.
- Center for Physiology and Pathophysiology, Institute for Neuro- and Sense Physiology, University Medical Center (UMG), Georg-August-University, Humboldtallee 23, 37073 Göttingen, Germany.
| | - Thomas A Bayer
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, von-Siebold-Strasse 5, 37075 Göttingen, Germany.
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27
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Dunkelmann T, Teichmann K, Ziehm T, Schemmert S, Frenzel D, Tusche M, Dammers C, Jürgens D, Langen KJ, Demuth HU, Shah NJ, Kutzsche J, Willuweit A, Willbold D. Aβ oligomer eliminating compounds interfere successfully with pEAβ(3-42) induced motor neurodegenerative phenotype in transgenic mice. Neuropeptides 2018; 67:27-35. [PMID: 29273382 DOI: 10.1016/j.npep.2017.11.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 11/24/2017] [Accepted: 11/26/2017] [Indexed: 10/18/2022]
Abstract
Currently, there are no causative or disease modifying treatments available for Alzheimer's disease (AD). Previously, it has been shown that D3, a small, fully d-enantiomeric peptide is able to eliminate low molecular weight Aβ oligomers in vitro, enhance cognition and reduce plaque load in AD transgenic mice. To further characterise the therapeutic potential of D3 towards N-terminally truncated and pyroglutamated Aβ (pEAβ(3-42)) we tested D3 and its head-to-tail tandem derivative D3D3 both in vitro and in vivo in the new mouse model TBA2.1. These mice produce human pEAβ(3-42) leading to a strong, early onset motor neurodegenerative phenotype. In the present study, we were able to demonstrate 1) strong binding affinity of both D3 and D3D3 to pEAβ(3-42) in comparison to Aβ(1-42) and 2) increased affinity of the tandem derivative D3D3 in comparison to D3. Subsequently we tested the therapeutic potentials of both peptides in the TBA2.1 animal model. Truly therapeutic, non-preventive treatment with D3 and D3D3 clearly slowed the progression of the neurodegenerative TBA2.1 phenotype, indicating the strong therapeutic potential of both peptides against pEAβ(3-42) induced neurodegeneration.
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Affiliation(s)
- Tina Dunkelmann
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Kerstin Teichmann
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Tamar Ziehm
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Sarah Schemmert
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Daniel Frenzel
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Markus Tusche
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Christina Dammers
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Dagmar Jürgens
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Karl-Josef Langen
- Institute of Neuroscience and Medicine (INM-4), Medical Imaging Physics, Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany; Department of Nuclear Medicine, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Hans-Ulrich Demuth
- Fraunhofer-Institute of Cell Therapy and Immunology (IZI), Leipzig, Department of Drug Design and Target Validation (MWT), Biozentrum, Weinbergweg 22, 06120 Halle, Germany
| | - Nadim Jon Shah
- Institute of Neuroscience and Medicine (INM-4), Medical Imaging Physics, Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany; Department of Neurology, Faculty of Medicine, JARA, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany; Department of Electrical and Computer Systems Engineering and Monash Biomedical Imaging, School of Psychological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Janine Kutzsche
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
| | - Antje Willuweit
- Institute of Neuroscience and Medicine (INM-4), Medical Imaging Physics, Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany.
| | - Dieter Willbold
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany; Institut für Physikalische Biologie, Heinrich Heine Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany.
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28
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McGraw CM, Ward CS, Samaco RC. Genetic rodent models of brain disorders: Perspectives on experimental approaches and therapeutic strategies. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 175:368-379. [PMID: 28910526 PMCID: PMC5659732 DOI: 10.1002/ajmg.c.31570] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 06/28/2017] [Indexed: 12/14/2022]
Abstract
Neurobehavioral disorders comprised of neurodegenerative, neurodevelopmental, and psychiatric disorders together represent leading causes of morbidity and mortality. Despite significant academic research and industry efforts to elucidate the disease mechanisms operative in these disorders and to develop mechanism‐based therapies, our understanding remains incomplete and our access to tractable therapeutic interventions severely limited. The magnitude of these short‐comings can be measured by the growing list of disappointing clinical trials based on initially promising compounds identified in genetic animal models. This review and commentary will explore why this may be so, focusing on the central role that genetic models of neurobehavioral disorders have come to occupy in current efforts to identify disease mechanisms and therapies. In particular, we will highlight the unique pitfalls and challenges that have hampered success in these models as compared to genetic models of non‐neurological diseases as well as to symptom‐based models of the early 20th century that led to the discovery of all major classes of psychoactive pharmaceutical compounds still used today. Using examples from specific genetic rodent models of human neurobehavioral disorders, we will highlight issues of reproducibility, construct validity, and translational relevance in the hopes that these examples will be instructive toward greater success in future endeavors. Lastly, we will champion a two‐pronged approach toward identifying novel therapies for neurobehavioral disorders that makes greater use of the historically more successful symptom‐based approaches in addition to more mechanism‐based approaches.
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Affiliation(s)
- Christopher M McGraw
- Department of Neurology, University of California, San Francisco, San Francisco, California
| | - Christopher S Ward
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Rodney C Samaco
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas.,Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, Texas
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29
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Abstract
The production of soluble amyloid-β oligomers (AβOs) and the activation of inflammation are two important early steps in the pathogenesis of Alzheimer's disease (AD). The central role of oligomers as responsible for the neuronal dysfunction associated with the clinical features has been extended to the other protein misfolding disorders definable, on this basis, as oligomeropathies. In AD, recent evidence indicates that the mechanism of inflammation as a consequence of neurodegeneration must be assessed in favor of a more direct role of glial activation in the alteration of synaptic function. Our own experimental models demonstrate the efficacy of anti-inflammatory treatments in preventing the cognitive deficits induced acutely by AβOs applied directly in the brain. Moreover, some promising clinical tools are based on immunological activation reducing the presence of cerebral Aβ deposits. However, the strategies based on the control of inflammatory factors as well as the amyloid aggregation show poor or non-therapeutic efficacy. Numerous studies have examined inflammatory factors in biological fluids as possible markers of the neuroinflammation in AD. In some cases, altered levels of cytokines or other inflammatory markers in cerebrospinal fluid correlate with the severity of the disease. Here we propose, according to the precision medicine principles, innovative therapeutic approaches to AD based on the patient's inflammatory profile/state. The earlier intervention and a multifactor approach are two other elements considered essential to improve the chances of effective therapy in AD.
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Affiliation(s)
- Gianluigi Forloni
- Department of Neuroscience, IRCCS, Istituto di Ricerche Farmacologiche “Mario Negri”, Milano, Italy
| | - Claudia Balducci
- Department of Neuroscience, IRCCS, Istituto di Ricerche Farmacologiche “Mario Negri”, Milano, Italy
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30
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Yu J, Kong L, Zhang A, Han Y, Liu Z, Sun H, Liu L, Wang X. High-Throughput Metabolomics for Discovering Potential Metabolite Biomarkers and Metabolic Mechanism from the APPswe/PS1dE9 Transgenic Model of Alzheimer’s Disease. J Proteome Res 2017; 16:3219-3228. [DOI: 10.1021/acs.jproteome.7b00206] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Jingbo Yu
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
| | - Ling Kong
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
| | - Aihua Zhang
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
| | - Ying Han
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
| | - Zhidong Liu
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
| | - Hui Sun
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
| | - Liang Liu
- State
Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China
| | - Xijun Wang
- Sino-America
Chinmedomics Technology Collaboration Center, National TCM Key Laboratory
of Serum Pharmacochemistry, Chinmedomics Research Center of State
Administration of TCM, Metabolomics Laboratory, Department of Pharmaceutical
Analysis, Heilongjiang University of Chinese Medicine, Heping Road
24, Harbin 150040, China
- State
Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China
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31
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Aβ truncated species: Implications for brain clearance mechanisms and amyloid plaque deposition. Biochim Biophys Acta Mol Basis Dis 2017; 1864:208-225. [PMID: 28711595 DOI: 10.1016/j.bbadis.2017.07.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/24/2017] [Accepted: 07/11/2017] [Indexed: 12/14/2022]
Abstract
Extensive parenchymal and vascular Aβ deposits are pathological hallmarks of Alzheimer's disease (AD). Besides classic full-length peptides, biochemical analyses of brain deposits have revealed high degree of Aβ heterogeneity likely resulting from the action of multiple proteolytic enzymes. In spite of the numerous studies focusing in Aβ, the relevance of N- and C-terminal truncated species for AD pathogenesis remains largely understudied. In the present work, using novel antibodies specifically recognizing Aβ species N-terminally truncated at position 4 or C-terminally truncated at position 34, we provide a clear assessment of the differential topographic localization of these species in AD brains and transgenic models. Based on their distinct solubility, brain N- and C-terminal truncated species were extracted by differential fractionation and identified via immunoprecipitation coupled to mass spectrometry analysis. Biochemical/biophysical studies with synthetic homologues further confirmed the different solubility properties and contrasting fibrillogenic characteristics of the truncated species composing the brain Aβ peptidome. Aβ C-terminal degradation leads to the production of more soluble fragments likely to be more easily eliminated from the brain. On the contrary, N-terminal truncation at position 4 favors the formation of poorly soluble, aggregation prone peptides with high amyloidogenic propensity and the potential to exacerbate the fibrillar deposits, self-perpetuating the amyloidogenic loop. Detailed assessment of the molecular diversity of Aβ species composing interstitial fluid and amyloid deposits at different disease stages, as well as the evaluation of the truncation profile during various pharmacologic approaches will provide a comprehensive understanding of the still undefined contribution of Aβ truncations to the disease pathogenesis and their potential as novel therapeutic targets.
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32
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Drew SC. The Case for Abandoning Therapeutic Chelation of Copper Ions in Alzheimer's Disease. Front Neurosci 2017; 11:317. [PMID: 28626387 PMCID: PMC5455140 DOI: 10.3389/fnins.2017.00317] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 05/18/2017] [Indexed: 12/26/2022] Open
Abstract
The "therapeutic chelation" approach to treating Alzheimer's disease (AD) evolved from the metals hypothesis, with the premise that small molecules can be designed to prevent transition metal-induced amyloid deposition and oxidative stress within the AD brain. Over more than 20 years, countless in vitro studies have been devoted to characterizing metal binding, its effect on Aβ aggregation, ROS production, and in vitro toxicity. Despite a lack of evidence for any clinical benefit, the conjecture that therapeutic chelation is an effective approach for treating AD remains widespread. Here, the author plays the devil's advocate, questioning the experimental evidence, the dogma, and the value of therapeutic chelation, with a major focus on copper ions.
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Affiliation(s)
- Simon C. Drew
- Department of Medicine, Royal Melbourne Hospital, University of MelbourneMelbourne, VIC, Australia
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33
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Li Y, Zhu X, Wang P, Wang J, Liu S, Li F, Qiu M. Detection of Aβ plaque deposition in MR images based on pixel feature selection and class information in image level. Biomed Eng Online 2016; 15:108. [PMID: 27632977 PMCID: PMC5025619 DOI: 10.1186/s12938-016-0222-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 08/10/2016] [Indexed: 01/17/2023] Open
Abstract
Background Amyloid β-protein (Aβ) plaque deposition is an important prevention and treatment target for Alzheimer’s disease (AD). As a noninvasive, nonradioactive and highly cost-effective clinical imaging method, magnetic resonance imaging (MRI) is the perfect imaging technology for the clinical diagnosis of AD, but it cannot display the plaque deposition directly. This paper resolves this problem based on pixel feature selection algorithms at the image level. Methods and results Firstly, the brain region was segmented from mouse model brain MR images. Secondly, the pixels in the segmented brain region were extracted as a feature vector (features). Thirdly, feature selection was conducted on the extracted features, and the optimal feature subset was obtained. Fourthly, the various optimal feature subsets were obtained by repeating the same processing above. Fifthly, based on the optimal feature subsets, the final optimal feature subset was obtained by voting mechanism. Finally, using the final optimal selected features, the corresponding pixels on the MR images could be found and marked to show the information about Aβ plaque deposition. The MR images and brain histological image slices of twenty-two model mice were used in the experiments. Four feature selection algorithms were used on the MR images and six kinds of classification experiments are conducted, thereby choosing a pixel feature selection algorithm for further study. The experimental results showed that by using the pixel features selected by the algorithms in this paper, the best classification accuracy between early AD and control slides could be as high as 80 %. The selected and marked MR pixels could show information of Aβ plaque deposition without missing most of the Aβ plaque deposition compared with brain histological slice images. The hit rate is over than 90 %. Conclusions According to the experimental results, the proposed detection algorithm of the Aβ plaque deposition based on MR pixel feature selection algorithm is effective. The proposed algorithm can detect the information of the Aβ plaque deposition on MR images and the information can be useful for improving the classification accuracy as assistant MR biomarker. Besides, these findings firstly show the feasibility of detection of the Aβ plaque deposition on MR images and provide reference method for interested relevant researchers in public.
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Affiliation(s)
- Yongming Li
- Department of Medical Image, College of Biomedical Engineering, Third Military Medical University, Chongqing, 400038, China. .,College of Communication Engineering, Chongqing University, Shapingba District, Chongqing, 400044, China.
| | - Xueru Zhu
- College of Communication Engineering, Chongqing University, Shapingba District, Chongqing, 400044, China
| | - Pin Wang
- College of Communication Engineering, Chongqing University, Shapingba District, Chongqing, 400044, China
| | - Jie Wang
- College of Communication Engineering, Chongqing University, Shapingba District, Chongqing, 400044, China
| | - Shujun Liu
- College of Communication Engineering, Chongqing University, Shapingba District, Chongqing, 400044, China
| | - Fan Li
- College of Communication Engineering, Chongqing University, Shapingba District, Chongqing, 400044, China
| | - Mingguo Qiu
- Department of Medical Image, College of Biomedical Engineering, Third Military Medical University, Chongqing, 400038, China.
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34
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Hüttenrauch M, Brauß A, Kurdakova A, Borgers H, Klinker F, Liebetanz D, Salinas-Riester G, Wiltfang J, Klafki HW, Wirths O. Physical activity delays hippocampal neurodegeneration and rescues memory deficits in an Alzheimer disease mouse model. Transl Psychiatry 2016; 6:e800. [PMID: 27138799 PMCID: PMC5070068 DOI: 10.1038/tp.2016.65] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 03/11/2016] [Indexed: 01/12/2023] Open
Abstract
The evidence for a protective role of physical activity on the risk and progression of Alzheimer's disease (AD) has been growing in the last years. Here we studied the influence of a prolonged physical and cognitive stimulation on neurodegeneration, with special emphasis on hippocampal neuron loss and associated behavioral impairment in the Tg4-42 mouse model of AD. Tg4-42 mice overexpress Aβ4-42 without any mutations, and develop an age-dependent hippocampal neuron loss associated with a severe memory decline. We demonstrate that long-term voluntary exercise diminishes CA1 neuron loss and completely rescues spatial memory deficits in different experimental settings. This was accompanied by changes in the gene expression profile of Tg4-42 mice. Deep sequencing analysis revealed an upregulation of chaperones involved in endoplasmatic reticulum protein processing, which might be intimately linked to the beneficial effects seen upon long-term exercise. We believe that we provide evidence for the first time that enhanced physical activity counteracts neuron loss and behavioral deficits in a transgenic AD mouse model. The present findings underscore the relevance of increased physical activity as a potential strategy in the prevention of dementia.
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Affiliation(s)
- M Hüttenrauch
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - A Brauß
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - A Kurdakova
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - H Borgers
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - F Klinker
- Department of Clinical
Neurophysiology, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - D Liebetanz
- Department of Clinical
Neurophysiology, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - G Salinas-Riester
- Department of Developmental
Biochemistry, DNA Microarray and Deep-Sequencing Facility, University
Medical Center (UMG), Georg-August-University,
Göttingen, Germany
| | - J Wiltfang
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
- German Center for Neurodegenerative
Diseases (DZNE), Göttingen, Germany
| | - H W Klafki
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
| | - O Wirths
- Department of Psychiatry and
Psychotherapy, University Medical Center (UMG),
Georg-August-University, Göttingen,
Germany
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