1
|
Khorsand FR, Aziziyan F, Khajeh K. Factors influencing amyloid fibril formation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2024; 206:55-83. [PMID: 38811089 DOI: 10.1016/bs.pmbts.2024.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Protein aggregation is a complex process with several stages that lead to the formation of complex structures and shapes with a broad variability in stability and toxicity. The aggregation process is affected by various factors and environmental conditions that disrupt the protein's original state, including internal factors like mutations, expression levels, and polypeptide chain truncation, as well as external factors, such as dense molecular surroundings, post-translation modifications, and interactions with other proteins, nucleic acids, small molecules, metal ions, chaperones, and lipid membranes. During the aggregation process, the biological activity of an aggregating protein may be reduced or eliminated, whereas the resulting aggregates may have the potential to be immunogenic, or they may have other undesirable properties. Finding the cause(s) of protein aggregation and controlling it to an acceptable level is among the most crucial topics of research in academia and biopharmaceutical companies. This chapter aims to review intrinsic pathways of protein aggregation and potential extrinsic variables that influence this process.
Collapse
Affiliation(s)
| | - Fatemeh Aziziyan
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Khosro Khajeh
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
| |
Collapse
|
2
|
Armbrust F, Bickenbach K, Altmeppen H, Foggetti A, Winkelmann A, Wulff P, Glatzel M, Pietrzik CU, Becker-Pauly C. A novel mouse model for N-terminal truncated Aβ2-x generation through meprin β overexpression in astrocytes. Cell Mol Life Sci 2024; 81:139. [PMID: 38480559 PMCID: PMC10937767 DOI: 10.1007/s00018-024-05139-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 03/17/2024]
Abstract
Neurotoxic amyloid-β (Aβ) peptides cause neurodegeneration in Alzheimer's disease (AD) patients' brains. They are released upon proteolytic processing of the amyloid precursor protein (APP) extracellularly at the β-secretase site and intramembranously at the γ-secretase site. Several AD mouse models were developed to conduct respective research in vivo. Most of these classical models overexpress human APP with mutations driving AD-associated pathogenic APP processing. However, the resulting pattern of Aβ species in the mouse brains differs from those observed in AD patients' brains. Particularly mutations proximal to the β-secretase cleavage site (e.g., the so-called Swedish APP (APPswe) fostering Aβ1-x formation) lead to artificial Aβ production, as N-terminally truncated Aβ peptides are hardly present in these mouse brains. Meprin β is an alternative β-secretase upregulated in brains of AD patients and capable of generating N-terminally truncated Aβ2-x peptides. Therefore, we aimed to generate a mouse model for the production of so far underestimated Aβ2-x peptides by conditionally overexpressing meprin β in astrocytes. We chose astrocytes as meprin β was detected in this cell type in close proximity to Aβ plaques in AD patients' brains. The meprin β-overexpressing mice showed elevated amyloidogenic APP processing detected with a newly generated neo-epitope-specific antibody. Furthermore, we observed elevated Aβ production from endogenous APP as well as AD-related behavior changes (hyperlocomotion and deficits in spatial memory). The novel mouse model as well as the established tools and methods will be helpful to further characterize APP cleavage and the impact of different Aβ species in future studies.
Collapse
Affiliation(s)
- Fred Armbrust
- Biochemical Institute, Unit for Degradomics of the Protease Web, University of Kiel, Otto-Hahn-Platz 9, 24118, Kiel, Germany.
| | - Kira Bickenbach
- Biochemical Institute, Unit for Degradomics of the Protease Web, University of Kiel, Otto-Hahn-Platz 9, 24118, Kiel, Germany
| | - Hermann Altmeppen
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Angelica Foggetti
- Institute of Physiology, University of Kiel, Kiel, Germany
- Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Haining, 314400, China
- College of Medicine & Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Anne Winkelmann
- Biochemical Institute, Unit for Degradomics of the Protease Web, University of Kiel, Otto-Hahn-Platz 9, 24118, Kiel, Germany
| | - Peer Wulff
- Institute of Physiology, University of Kiel, Kiel, Germany
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Claus U Pietrzik
- Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Christoph Becker-Pauly
- Biochemical Institute, Unit for Degradomics of the Protease Web, University of Kiel, Otto-Hahn-Platz 9, 24118, Kiel, Germany.
| |
Collapse
|
3
|
Poejo J, Berrocal M, Saez L, Gutierrez-Merino C, Mata AM. Store-Operated Calcium Entry Inhibition and Plasma Membrane Calcium Pump Upregulation Contribute to the Maintenance of Resting Cytosolic Calcium Concentration in A1-like Astrocytes. Molecules 2023; 28:5363. [PMID: 37513235 PMCID: PMC10383710 DOI: 10.3390/molecules28145363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/30/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Highly neurotoxic A1-reactive astrocytes have been associated with several human neurodegenerative diseases. Complement protein C3 expression is strongly upregulated in A1 astrocytes, and this protein has been shown to be a specific biomarker of these astrocytes. Several cytokines released in neurodegenerative diseases have been shown to upregulate the production of amyloid β protein precursor (APP) and neurotoxic amyloid β (Aβ) peptides in reactive astrocytes. Also, aberrant Ca2+ signals have been proposed as a hallmark of astrocyte functional remodeling in Alzheimer's disease mouse models. In this work, we induced the generation of A1-like reactive astrocytes after the co-treatment of U251 human astroglioma cells with a cocktail of the cytokines TNF-α, IL1-α and C1q. These A1-like astrocytes show increased production of APP and Aβ peptides compared to untreated U251 cells. Additionally, A1-like astrocytes show a (75 ± 10)% decrease in the Ca2+ stored in the endoplasmic reticulum (ER), (85 ± 10)% attenuation of Ca2+ entry after complete Ca2+ depletion of the ER, and three-fold upregulation of plasma membrane calcium pump expression, with respect to non-treated Control astrocytes. These altered intracellular Ca2+ dynamics allow A1-like astrocytes to efficiently counterbalance the enhanced release of Ca2+ from the ER, preventing a rise in the resting cytosolic Ca2+ concentration.
Collapse
Affiliation(s)
- Joana Poejo
- Instituto de Biomarcadores de Patologías Moleculares (IBPM), Universidad de Extremadura, 06006 Badajoz, Spain
| | - María Berrocal
- Instituto de Biomarcadores de Patologías Moleculares (IBPM), Universidad de Extremadura, 06006 Badajoz, Spain
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Lucía Saez
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Carlos Gutierrez-Merino
- Instituto de Biomarcadores de Patologías Moleculares (IBPM), Universidad de Extremadura, 06006 Badajoz, Spain
| | - Ana M Mata
- Instituto de Biomarcadores de Patologías Moleculares (IBPM), Universidad de Extremadura, 06006 Badajoz, Spain
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain
| |
Collapse
|
4
|
Ablinger I, Dressel K, Rott T, Lauer AA, Tiemann M, Batista JP, Taddey T, Grimm HS, Grimm MOW. Interdisciplinary Approaches to Deal with Alzheimer's Disease-From Bench to Bedside: What Feasible Options Do Already Exist Today? Biomedicines 2022; 10:2922. [PMID: 36428494 PMCID: PMC9687885 DOI: 10.3390/biomedicines10112922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/03/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Alzheimer's disease is one of the most common neurodegenerative diseases in the western population. The incidence of this disease increases with age. Rising life expectancy and the resulting increase in the ratio of elderly in the population are likely to exacerbate socioeconomic problems. Alzheimer's disease is a multifactorial disease. In addition to amyloidogenic processing leading to plaques, and tau pathology, but also other molecular causes such as oxidative stress or inflammation play a crucial role. We summarize the molecular mechanisms leading to Alzheimer's disease and which potential interventions are known to interfere with these mechanisms, focusing on nutritional approaches and physical activity but also the beneficial effects of cognition-oriented treatments with a focus on language and communication. Interestingly, recent findings also suggest a causal link between oral conditions, such as periodontitis or edentulism, and Alzheimer's disease, raising the question of whether dental intervention in Alzheimer's patients can be beneficial as well. Unfortunately, all previous single-domain interventions have been shown to have limited benefit to patients. However, the latest studies indicate that combining these efforts into multidomain approaches may have increased preventive or therapeutic potential. Therefore, as another emphasis in this review, we provide an overview of current literature dealing with studies combining the above-mentioned approaches and discuss potential advantages compared to monotherapies. Considering current literature and intervention options, we also propose a multidomain interdisciplinary approach for the treatment of Alzheimer's disease patients that synergistically links the individual approaches. In conclusion, this review highlights the need to combine different approaches in an interdisciplinary manner, to address the future challenges of Alzheimer's disease.
Collapse
Affiliation(s)
- Irene Ablinger
- Speech and Language Therapy, Campus Bonn, SRH University of Applied Health Sciences, 53111 Bonn, Germany
| | - Katharina Dressel
- Speech and Language Therapy, Campus Düsseldorf, SRH University of Applied Health Sciences, 40210 Düsseldorf, Germany
| | - Thea Rott
- Interdisciplinary Periodontology and Prevention, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
| | - Anna Andrea Lauer
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
- Experimental Neurology, Saarland University, 66424 Homburg, Germany
| | - Michael Tiemann
- Sport Science, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
| | - João Pedro Batista
- Sport Science and Physiotherapy, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
| | - Tim Taddey
- Physiotherapy, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
| | - Heike Sabine Grimm
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
- Experimental Neurology, Saarland University, 66424 Homburg, Germany
| | - Marcus Otto Walter Grimm
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
- Experimental Neurology, Saarland University, 66424 Homburg, Germany
| |
Collapse
|
5
|
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: 5] [Impact Index Per Article: 2.5] [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.
Collapse
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
| |
Collapse
|
6
|
Noor A, Zafar S, Shafiq M, Younas N, Siegert A, Mann FA, Kruss S, Schmitz M, Dihazi H, Ferrer I, Zerr I. Molecular Profiles of Amyloid-β Proteoforms in Typical and Rapidly Progressive Alzheimer's Disease. Mol Neurobiol 2021; 59:17-34. [PMID: 34618331 PMCID: PMC8786784 DOI: 10.1007/s12035-021-02566-9] [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: 06/24/2021] [Accepted: 09/13/2021] [Indexed: 11/02/2022]
Abstract
The molecular determinants of atypical clinical variants of Alzheimer's disease, including the recently discovered rapidly progressive Alzheimer's disease (rpAD), are unknown to date. Fibrilization of the amyloid-β (Aβ) peptide is the most frequently studied candidate in this context. The Aβ peptide can exist as multiple proteoforms that vary in their post-translational processing, amyloidogenesis, and toxicity. The current study was designed to identify these variations in Alzheimer's disease patients exhibiting classical (sAD) and rapid progression, with the primary aim of establishing if these variants may constitute strains that underlie the phenotypic variability of Alzheimer's disease. We employed two-dimensional polyacrylamide gel electrophoresis and MALDI-ToF mass spectrometry to validate and identify the Aβ proteoforms extracted from targeted brain tissues. The biophysical analysis was conducted using RT-QuIC assay, confocal microscopy, and atomic force microscopy. Interactome analysis was performed by co-immunoprecipitation. We present a signature of 33 distinct pathophysiological proteoforms, including the commonly targeted Aβ40, Aβ42, Aβ4-42, Aβ11-42, and provide insight into their synthesis and quantities. Furthermore, we have validated the presence of highly hydrophobic Aβ seeds in rpAD brains that seeded reactions at a slower pace in comparison to typical Alzheimer's disease. In vitro and in vivo analyses also verified variations in the molecular pathways modulated by brain-derived Aβ. These variations in the presence, synthesis, folding, and interactions of Aβ among sAD and rpAD brains constitute important points of intervention. Further validation of reported targets and mechanisms will aid in the diagnosis of and therapy for Alzheimer's disease.
Collapse
Affiliation(s)
- Aneeqa Noor
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Saima Zafar
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany. .,Biomedical Engineering and Sciences Department, School of Mechanical and Manufacturing Engineering (SMME), National University of Sciences and Technology (NUST), Bolan Road, Islamabad, H-12, 44000, Pakistan.
| | - Mohsin Shafiq
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany.,Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Neelam Younas
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Anna Siegert
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Florian A Mann
- Institute of Physical Chemistry, Georg-August University, Tammannstraße 6, 37077, Göttingen, Germany
| | - Sebastian Kruss
- Institute of Physical Chemistry, Georg-August University, Tammannstraße 6, 37077, Göttingen, Germany
| | - Matthias Schmitz
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Hassan Dihazi
- Department of Nephrology and Rheumatology, Georg-August University, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Isidre Ferrer
- Department of Pathology and Experimental Therapeutics, University of BarcelonaCIBERNEDBellvitge University Hospital (IDIBELL), Carrer de la Feixa Llarga, 08907, Hospitalet de Llobregat, Spain
| | - Inga Zerr
- Clinical Department of Neurology, University Medical Center Göttingen and the German Center for Neurodegenerative Diseases (DZNE), Robert-Koch-Straße 40, 37075, Göttingen, Germany
| |
Collapse
|
7
|
Temporal lobe epilepsy: Evaluation of central and systemic immune-inflammatory features associated with drug resistance. Seizure 2021; 91:447-455. [PMID: 34340190 DOI: 10.1016/j.seizure.2021.07.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 07/13/2021] [Accepted: 07/21/2021] [Indexed: 12/21/2022] Open
Abstract
Neuroinflammation is probably one of the factors involved in drug resistance in people with epilepsy. Finding peripheral markers reflecting the intensity of neuroinflammation could be of great help to decide for which patients anti-inflammatory treatment might be an option. In this context, peripheral cytokines levels and lymphocyte phenotypes were assessed by ELISA and flow cytometry in 3 groups of subjects: drug resistant patients with temporal lobe epilepsy (DR-TLE), non DR-TLE patients and healthy controls. The same parameters were assessed in brain tissue in the DR-TLE group. Differences in the peripheral immune-inflammatory status between the 3 groups of subjects, and correlations between the central and peripheral immune-inflammatory status in DR-TLE patients were evaluated. Forty-one patients with DR-TLE, ten with non-DR-TLE and twenty controls were included. In the periphery, decrease in regulatory cells were observed in DR-TLE patients compared to controls. In addition, significant increase of IL-6 and IL-5 was observed in patients with epilepsy (particularly DR-TLE patients). Two groups of DR-TLE patients with significant differences in several central inflammatory parameters were identified in a cluster analysis. The inflammatory cluster was associated with a peripheral increase of CD4+CD38+ cells and different significant correlations between central and systemic inflammatory parameters were observed. Although their interpretation is not immediate, they demonstrate a clear dialogue between central and peripheral inflammatory reactions. In conclusion, our results add new elements to better understand the interactions between the central and peripheral compartments in patients with DR-TLE, and to help better define treatment options in this group of patients.
Collapse
|
8
|
Oberstein TJ, Utz J, Spitzer P, Klafki HW, Wiltfang J, Lewczuk P, Kornhuber J, Maler JM. The Role of Cathepsin B in the Degradation of Aβ and in the Production of Aβ Peptides Starting With Ala2 in Cultured Astrocytes. Front Mol Neurosci 2021; 13:615740. [PMID: 33510618 PMCID: PMC7836726 DOI: 10.3389/fnmol.2020.615740] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/03/2020] [Indexed: 11/13/2022] Open
Abstract
Astrocytes may not only be involved in the clearance of Amyloid beta peptides (Aβ) in Alzheimer's disease (AD), but appear to produce N-terminally truncated Aβ (Aβn−x) independently of BACE1, which generates the N-Terminus of Aβ starting with Asp1 (Aβ1−x). A candidate protease for the generation of Aβn−x is cathepsin B (CatB), especially since CatB has also been reported to degrade Aβ, which could explain the opposite roles of astrocytes in AD. In this study, we investigated the influence of CatB inhibitors and the deletion of the gene encoding CatB (CTSB) using CRISPR/Cas9 technology on Aβ2−x and Aβ1−x levels in cell culture supernatants by one- and two-dimensional Urea-SDS-PAGE followed by immunoblot. While the cell-permeant inhibitors E64d and CA-074 Me did not significantly affect the Aβ1−x levels in supernatants of cultured chicken and human astrocytes, they did reduce the Aβ2−x levels. In the glioma-derived cell line H4, the Aβ2−x levels were likewise decreased in supernatants by treatment with the more specific, but cell-impermeant CatB-inhibitor CA-074, by CA-074 Me treatment, and by CTSB gene deletion. Additionally, a more than 2-fold increase in secreted Aβ1−x was observed under the latter two conditions. The CA-074 Me-mediated increase of Aβ1−x, but not the decrease of Aβ2−x, was influenced by concomitant treatment with the vacuolar H+-ATPase inhibitor Bafilomycin A1. This indicated that non-lysosomal CatB mediated the production of Aβ2−x in astrocytes, while the degradation of Aβ1−x seemed to be dependent on lysosomal CatB in H4 cells, but not in primary astrocytes. These findings highlight the importance of considering organelle targeting in drug development to promote Aβ degradation.
Collapse
Affiliation(s)
- Timo Jan Oberstein
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Janine Utz
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Philipp Spitzer
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Hans Wolfgang Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center, Georg-August-University, Göttingen, Germany
| | - Jens Wiltfang
- Department of Psychiatry and Psychotherapy, University Medical Center, Georg-August-University, Göttingen, Germany.,German Center for Neurodegenerative Diseases, Göttingen, Germany.,Neurosciences and Signaling Group, Department of Medical Sciences, Institute of Biomedicine, University of Aveiro, Aveiro, Portugal
| | - Piotr Lewczuk
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany.,Department of Neurodegeneration Diagnostics and Department of Biochemical Diagnostics, University Hospital of Bialystok, Bialystok, Poland
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Juan Manuel Maler
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
9
|
Hunter S, Brayne C. Amyloid in the ageing brain: New frameworks and perspectives. AGING BRAIN 2021; 1:100008. [PMID: 36911501 PMCID: PMC9997141 DOI: 10.1016/j.nbas.2021.100008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 01/23/2023] Open
Affiliation(s)
- Sally Hunter
- Cambridge Public Health, University of Cambridge School of Clinical Medicine, Forvie Site, Cambridge Biomedical Campus, Cambridge CB2 0SR, United Kingdom
| | - Carol Brayne
- Cambridge Public Health, University of Cambridge School of Clinical Medicine, Forvie Site, Cambridge Biomedical Campus, Cambridge CB2 0SR, United Kingdom
| |
Collapse
|
10
|
Development and Technical Validation of an Immunoassay for the Detection of APP 669-711 (Aβ -3-40) in Biological Samples. Int J Mol Sci 2020; 21:ijms21186564. [PMID: 32911706 PMCID: PMC7555726 DOI: 10.3390/ijms21186564] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 01/10/2023] Open
Abstract
The ratio of amyloid precursor protein (APP)669-711 (Aβ-3-40)/Aβ1-42 in blood plasma was reported to represent a novel Alzheimer's disease biomarker. Here, we describe the characterization of two antibodies against the N-terminus of Aβ-3-x and the development and "fit-for-purpose" technical validation of a sandwich immunoassay for the measurement of Aβ-3-40. Antibody selectivity was assessed by capillary isoelectric focusing immunoassay, Western blot analysis, and immunohistochemistry. The analytical validation addressed assay range, repeatability, specificity, between-run variability, impact of pre-analytical sample handling procedures, assay interference, and analytical spike recoveries. Blood plasma was analyzed after Aβ immunoprecipitation by a two-step immunoassay procedure. Both monoclonal antibodies detected Aβ-3-40 with no appreciable cross reactivity with Aβ1-40 or N-terminally truncated Aβ variants. However, the amyloid precursor protein was also recognized. The immunoassay showed high selectivity for Aβ-3-40 with a quantitative assay range of 22 pg/mL-7.5 ng/mL. Acceptable intermediate imprecision of the complete two-step immunoassay was reached after normalization. In a small clinical sample, the measured Aβ42/Aβ-3-40 and Aβ42/Aβ40 ratios were lower in patients with dementia of the Alzheimer's type than in other dementias. In summary, the methodological groundwork for further optimization and future studies addressing the Aβ42/Aβ-3-40 ratio as a novel biomarker candidate for Alzheimer's disease has been set.
Collapse
|
11
|
The impact of capsaicinoids on APP processing in Alzheimer's disease in SH-SY5Y cells. Sci Rep 2020; 10:9164. [PMID: 32514053 PMCID: PMC7280252 DOI: 10.1038/s41598-020-66009-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 05/11/2020] [Indexed: 11/08/2022] Open
Abstract
The vanilloid capsaicin is a widely consumed spice, known for its burning and "hot" sensation through activation of TRPV1 ion-channels, but also known to decrease oxidative stress, inflammation and influence tau-pathology. Beside these positive effects, little is known about its effects on amyloid-precursor-protein (APP) processing leading to amyloid-β (Aβ), the major component of senile plaques. Treatment of neuroblastoma cells with capsaicinoids (24 hours, 10 µM) resulted in enhanced Aβ-production and reduced Aβ-degradation, leading to increased Aβ-levels. In detailed analysis of the amyloidogenic-pathway, both BACE1 gene-expression as well as protein-levels were found to be elevated, leading to increased β-secretase-activity. Additionally, γ-secretase gene-expression as well as activity was enhanced, accompanied by a shift of presenilin from non-raft to raft membrane-domains where amyloidogenic processing takes place. Furthermore, impaired Aβ-degradation in presence of capsaicinoids is dependent on the insulin-degrading-enzyme, one of the major Aβ-degrading-enzymes. Regarding Aβ-homeostasis, no differences were found between the major capsaicinoids, capsaicin and dihydrocapsaicin, and a mixture of naturally derived capsaicinoids; effects on Ca2+-homeostasis were ruled out. Our results show that in respect to Alzheimer's disease, besides the known positive effects of capsaicinoids, pro-amyloidogenic properties also exist, enhancing Aβ-levels, likely restricting the potential use of capsaicinoids as therapeutic substances in Alzheimer's disease.
Collapse
|
12
|
Hornung K, Zampar S, Engel N, Klafki H, Liepold T, Bayer TA, Wiltfang J, Jahn O, Wirths O. N-Terminal Truncated Aβ4-42 Is a Substrate for Neprilysin Degradation in vitro and in vivo. J Alzheimers Dis 2020; 67:849-858. [PMID: 30664509 DOI: 10.3233/jad-181134] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In sporadic Alzheimer's disease (AD), an imbalance between production and clearance of amyloid-β (Aβ) peptides seems to account for enhanced Aβ accumulation. The metalloprotease neprilysin (NEP) is an important Aβ degrading enzyme as shown by a variety of in vitro and in vivo studies. While the degradation of full-length Aβ peptides such as Aβ1-40 and Aβ1-42 is well established, it is less clear whether NEP is also capable of degrading N-terminally truncated Aβ species such as the common variant Aβ4-42. In the present report, we confirmed the degradation of Aβ4-x species by neprilysin using in vitro digestion and subsequent analysis using gel-based assays and mass spectrometry. By crossing Tg4-42 mice expressing only Aβ4-42 peptides with homozygous NEP-knock-out mice (NEP-/-), we were able to demonstrate that NEP deficiency increased hippocampal intraneuronal Aβ levels and aggravated neuron loss in the Tg4-42 transgenic mouse model of AD.
Collapse
Affiliation(s)
- Karen Hornung
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany
| | - Silvia Zampar
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany
| | - Nadine Engel
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany
| | - Hans Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany
| | - Thomas Liepold
- Max Planck Institute of Experimental Medicine, Proteomics Group, Goettingen, Germany
| | - Thomas A Bayer
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany
| | - Jens Wiltfang
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany.,German Center for Neurodegenerative Diseases (DZNE), Goettingen, Germany.,Department of iBiMED, Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Olaf Jahn
- Max Planck Institute of Experimental Medicine, Proteomics Group, Goettingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Goettingen, Germany
| |
Collapse
|
13
|
Eede P, Obst J, Benke E, Yvon-Durocher G, Richard BC, Gimber N, Schmoranzer J, Böddrich A, Wanker EE, Prokop S, Heppner FL. Interleukin-12/23 deficiency differentially affects pathology in male and female Alzheimer's disease-like mice. EMBO Rep 2020; 21:e48530. [PMID: 32003148 PMCID: PMC7054677 DOI: 10.15252/embr.201948530] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 12/19/2019] [Accepted: 01/08/2020] [Indexed: 12/30/2022] Open
Abstract
Pathological aggregation of amyloid‐β (Aβ) is a main hallmark of Alzheimer's disease (AD). Recent genetic association studies have linked innate immune system actions to AD development, and current evidence suggests profound gender differences in AD pathogenesis. Here, we characterise gender‐specific pathologies in the APP23 AD‐like mouse model and find that female mice show stronger amyloidosis and astrogliosis compared with male mice. We tested the gender‐specific effect of lack of IL12p40, the shared subunit of interleukin (IL)‐12 and IL‐23, that we previously reported to ameliorate pathology in APPPS1 mice. IL12p40 deficiency gender specifically reduces Aβ plaque burden in male APP23 mice, while in female mice, a significant reduction in soluble Aβ1–40 without changes in Aβ plaque burden is seen. Similarly, plasma and brain cytokine levels are altered differently in female versus male APP23 mice lacking IL12p40, while glial properties are unchanged. These data corroborate the therapeutic potential of targeting IL‐12/IL‐23 signalling in AD, but also highlight the importance of gender considerations when studying the role of the immune system and AD.
Collapse
Affiliation(s)
- Pascale Eede
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Juliane Obst
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Eileen Benke
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Genevieve Yvon-Durocher
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Bernhard C Richard
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Niclas Gimber
- Advanced Medical Bioimaging Core Facility (AMBIO), corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jan Schmoranzer
- Advanced Medical Bioimaging Core Facility (AMBIO), corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Annett Böddrich
- Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Erich E Wanker
- Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Stefan Prokop
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Frank L Heppner
- Department of Neuropathology, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Cluster of Excellence, NeuroCure, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany
| |
Collapse
|
14
|
Tan JZA, Fourriere L, Wang J, Perez F, Boncompain G, Gleeson PA. Distinct anterograde trafficking pathways of BACE1 and amyloid precursor protein from the TGN and the regulation of amyloid-β production. Mol Biol Cell 2020; 31:27-44. [PMID: 31746668 PMCID: PMC6938271 DOI: 10.1091/mbc.e19-09-0487] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 11/01/2019] [Accepted: 11/15/2019] [Indexed: 01/08/2023] Open
Abstract
Processing of amyloid precursor protein (APP) by the β-secretase BACE1 is the initial step of the amyloidogenic pathway to generate amyloid-β (Aβ). Although newly synthesized BACE1 and APP are transported along the secretory pathway, it is not known whether BACE1 and APP share the same post-Golgi trafficking pathways or are partitioned into different transport routes. Here we demonstrate that BACE1 exits the Golgi in HeLa cells and primary neurons by a pathway distinct from the trafficking pathway for APP. By using the Retention Using Selective Hooks system, we show that BACE1 is transported from the trans-Golgi network to the plasma membrane in an AP-1- and Arf1/4-dependent manner. Subsequently, BACE1 is endocytosed to early and recycling endosomes. Perturbation of BACE1 post-Golgi trafficking results in an increase in BACE1 cleavage of APP and increased production of both Aβ40 and Aβ42. These findings reveal that Golgi exit of BACE1 and APP in primary neurons is tightly regulated, resulting in their segregation along different transport routes, which limits APP processing.
Collapse
Affiliation(s)
- Jing Zhi A. Tan
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Lou Fourriere
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Jingqi Wang
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Franck Perez
- Dynamics of Intracellular Organization Laboratory, Institut Curie, PSL Research University, Sorbonne Université, Centre National de la Recherche Scientifique, UMR 144, 75248 Paris, France
| | - Gaelle Boncompain
- Dynamics of Intracellular Organization Laboratory, Institut Curie, PSL Research University, Sorbonne Université, Centre National de la Recherche Scientifique, UMR 144, 75248 Paris, France
| | - Paul A. Gleeson
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| |
Collapse
|
15
|
Bastrup J, Birkelund S, Asuni AA, Volbracht C, Stensballe A. Dual strategy for reduced signal-suppression effects in matrix-assisted laser desorption/ionization mass spectrometry imaging. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:1711-1721. [PMID: 31307118 DOI: 10.1002/rcm.8521] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 05/16/2019] [Accepted: 07/01/2019] [Indexed: 06/10/2023]
Abstract
RATIONALE The molecular complexity of tissue features several signal-suppression effects which reduce the ionization of analytes significantly and thereby weakens the quality of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) imaging (MALDI imaging). We report a novel approach in MALDI imaging by reducing signal-suppression effects for the analysis of beta-amyloid (Aβ) plaques, one pathological hallmark of Alzheimer's disease (AD). METHODS We analyzed Aβ proteoforms from postmortem AD brains and brains from transgenic mice (APPPS1-21) overexpressing familial AD mutations by combining two techniques: (1) laser capture microdissection (LCM) to accumulate Aβ plaques and (2) phosphoric acid (PA) as additive to the super-2,5-dihydroxybenzoic acid matrix. RESULTS LCM and MALDI-MS enabled tandem mass spectrometric fragmentation of stained Aβ plaques. PA improved the signal-to-noise (S/N) ratio, especially of the Aβ1-42 peptide, by three-fold compared with the standard matrix additive trifluoroacetic acid. The beneficial effect of the PA matrix additive in MALDI imaging was particularly important for AD brain tissue. We identified several significant differences in Aβ plaque composition from AD compared with APPPS1-21, underlining the value of reducing signal-suppressing effects in MALDI imaging. CONCLUSIONS We present a novel strategy for overcoming signal-suppression effects in MALDI imaging of Aβ proteoforms.
Collapse
Affiliation(s)
- Joakim Bastrup
- Department of Health Science and Technology, Aalborg University, 9220, Aalborg East, Denmark
- Neuroscience, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Svend Birkelund
- Department of Health Science and Technology, Aalborg University, 9220, Aalborg East, Denmark
| | - Ayodeji A Asuni
- Neuroscience, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | | | - Allan Stensballe
- Department of Health Science and Technology, Aalborg University, 9220, Aalborg East, Denmark
| |
Collapse
|
16
|
Janitschke D, Nelke C, Lauer AA, Regner L, Winkler J, Thiel A, Grimm HS, Hartmann T, Grimm MOW. Effect of Caffeine and Other Methylxanthines on Aβ-Homeostasis in SH-SY5Y Cells. Biomolecules 2019; 9:biom9110689. [PMID: 31684105 PMCID: PMC6920871 DOI: 10.3390/biom9110689] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/25/2019] [Accepted: 10/30/2019] [Indexed: 02/07/2023] Open
Abstract
Methylxanthines (MTX) are alkaloids derived from the purine-base xanthine. Whereas especially caffeine, the most prominent known MTX, has been formerly assessed to be detrimental, this point of view has changed substantially. MTXs are discussed to have beneficial properties in neurodegenerative diseases, however, the mechanisms of action are not completely understood. Here we investigate the effect of the naturally occurring caffeine, theobromine and theophylline and the synthetic propentofylline and pentoxifylline on processes involved in Alzheimer’s disease (AD). All MTXs decreased amyloid-β (Aβ) level by shifting the amyloid precursor protein (APP) processing from the Aβ-producing amyloidogenic to the non-amyloidogenic pathway. The α-secretase activity was elevated whereas β-secretase activity was decreased. Breaking down the molecular mechanism, caffeine increased protein stability of the major α-secretase ADAM10, downregulated BACE1 expression and directly decreased β-secretase activity. Additionally, APP expression was reduced. In line with literature, MTXs reduced oxidative stress, decreased cholesterol and a decreased in Aβ1-42 aggregation. In conclusion, all MTXs act via the pleiotropic mechanism resulting in decreased Aβ and show beneficial properties with respect to AD in neuroblastoma cells. However, the observed effect strength was moderate, suggesting that MTXs should be integrated in a healthy diet rather than be used exclusively to treat or prevent AD.
Collapse
Affiliation(s)
- Daniel Janitschke
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Christopher Nelke
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Anna Andrea Lauer
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Liesa Regner
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Jakob Winkler
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Andrea Thiel
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Heike Sabine Grimm
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
| | - Tobias Hartmann
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
- Deutsches Institut für DemenzPrävention (DIDP), Saarland University, 66424 Homburg/Saar, Germany.
| | - Marcus Otto Walter Grimm
- Experimental Neurology, Saarland University, 66424 Homburg/Saar, Germany.
- Deutsches Institut für DemenzPrävention (DIDP), Saarland University, 66424 Homburg/Saar, Germany.
| |
Collapse
|
17
|
Bie B, Wu J, Foss JF, Naguib M. Activation of mGluR1 Mediates C1q-Dependent Microglial Phagocytosis of Glutamatergic Synapses in Alzheimer's Rodent Models. Mol Neurobiol 2019; 56:5568-5585. [PMID: 30652266 DOI: 10.1007/s12035-019-1467-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 01/04/2019] [Indexed: 12/29/2022]
Abstract
Microglia and complements appear to be involved in the synaptic and cognitive deficits in Alzheimer's disease (AD), though the mechanisms remain elusive. In this study, utilizing two types of rodent model of AD, we reported increased complement C1q-mediated microglial phagocytosis of hippocampal glutamatergic synapses, which led to synaptic and cognitive deficits. We also found increased activity of the metabotropic glutamate receptor 1 (mGluR1) in hippocampal CA1 in the modeled rodents. Artificial activation of mGluR1 signaling promoted dephosphorylation of fragile X mental retardation protein (FMRP) and facilitated the local translation machinery of synaptic C1q mRNA, thus mimicking the C1q-mediated microglial phagocytosis of hippocampal glutamatergic synapses and synaptic and cognitive deficiency in the modeled rodents. However, suppression of mGluR1 signaling inhibited the dephosphorylation of FMRP and repressed the local translation of synaptic C1q mRNA, which consequently alleviated microglial phagocytosis of synapses and restored the synaptic and cognitive function in the rodent models. These findings illustrate a novel molecular mechanism underlying C1q-mediated microglial phagocytosis of hippocampal glutamatergic synapses in AD.
Collapse
Affiliation(s)
- Bihua Bie
- Anesthesiology Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH, 44195, USA
| | - Jiang Wu
- Anesthesiology Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH, 44195, USA
| | - Joseph F Foss
- Anesthesiology Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH, 44195, USA
| | - Mohamed Naguib
- Anesthesiology Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH, 44195, USA. .,Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, 9500 Euclid Ave., Mail Code NB3-78, Cleveland, OH, 44195, USA.
| |
Collapse
|
18
|
Hüttenrauch M, Ogorek I, Klafki H, Otto M, Stadelmann C, Weggen S, Wiltfang J, Wirths O. Glycoprotein NMB: a novel Alzheimer's disease associated marker expressed in a subset of activated microglia. Acta Neuropathol Commun 2018; 6:108. [PMID: 30340518 PMCID: PMC6194687 DOI: 10.1186/s40478-018-0612-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/02/2018] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD) is an irreversible, devastating neurodegenerative brain disorder characterized by the loss of neurons and subsequent cognitive decline. Despite considerable progress in the understanding of the pathophysiology of AD, the precise molecular mechanisms that cause the disease remain elusive. By now, there is ample evidence that activated microglia have a critical role in the initiation and progression of AD. The present study describes the identification of Glycoprotein nonmetastatic melanoma protein B (GPNMB) as a novel AD-related factor in both transgenic mice and sporadic AD patients by expression profiling, immunohistochemistry and ELISA measurements. We show that GPNMB levels increase in an age-dependent manner in transgenic AD models showing profound cerebral neuron loss and demonstrate that GPNMB co-localizes with a distinct population of IBA1-positive microglia cells that cluster around amyloid plaques. Our data further indicate that GPNMB is part of a microglia activation state that is only present under neurodegenerative conditions and that is characterized by the up-regulation of a subset of genes including TREM2, APOE and CST7. In agreement, we provide in vitro evidence that soluble Aβ has a direct effect on GPNMB expression in an immortalized microglia cell line. Importantly, we show for the first time that GPNMB is elevated in brain samples and cerebrospinal fluid (CSF) of sporadic AD patients when compared to non-demented controls. The current findings indicate that GPNMB represents a novel disease-associated marker that appears to play a role in the neuroinflammatory response of AD.
Collapse
|
19
|
Lanza V, Bellia F, Rizzarelli E. An inorganic overview of natural Aβ fragments: Copper(II) and zinc(II)-mediated pathways. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.04.004] [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]
|
20
|
Galante D, Cavallo E, Perico A, D'Arrigo C. Effect of ferric citrate on amyloid-beta peptides behavior. Biopolymers 2018; 109:e23224. [PMID: 29897618 DOI: 10.1002/bip.23224] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/06/2018] [Accepted: 04/19/2018] [Indexed: 12/26/2022]
Abstract
Amyloid beta (Aβ) aggregation and oxidative stress are two of the central events in Alzheimer's Disease (AD). Both these phenomena can be caused by the interaction of Aβ with metal ions. In the last years the interaction between ZnII , CuII , and Aβ was much studied, but between iron and Aβ it is still little known. In this work we determine how three Aβ peptides, present in AD, interact with FeIII -citrate. The three Aβ peptides are: full length Aβ1-42, an isoform truncated at Glutamic acid in position three, Aβ3-42, and its pyroglutamated form AβpE3-42. Conformation and morphology of the three peptides, aggregated with and without FeIII -citrate were studied. Besides, we have determined the strength of the interactions Aβ/FeIII -citrate studying the effect of ethylenediaminetetraacetic acid as chelator. Results reported here demonstrate that FeIII -citrate promotes the aggregation in all the three peptides. Moreover, Aspartic acid 1, Glutamic acid 3, and Tyrosine 10 have an important role in the coordination with iron, generating a more stable complex for Aβ1-42 compared to that for the truncated peptides.
Collapse
Affiliation(s)
- D Galante
- Institute for Macromolecular Studies, National Research Council, Genova, 16149, Italy
| | - E Cavallo
- Institute for Macromolecular Studies, National Research Council, Genova, 16149, Italy.,Department of Chemistry and Industrial Chemistry, University of Genova, Via Dodecaneso 31, Genova, 16146, Italy
| | - A Perico
- Institute for Macromolecular Studies, National Research Council, Genova, 16149, Italy
| | - C D'Arrigo
- Institute for Macromolecular Studies, National Research Council, Genova, 16149, Italy
| |
Collapse
|
21
|
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.
Collapse
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
| |
Collapse
|
22
|
Hartlage-Rübsamen M, Bluhm A, Piechotta A, Linnert M, Rahfeld JU, Demuth HU, Lues I, Kuhn PH, Lichtenthaler SF, Roßner S, Höfling C. Immunohistochemical Evidence from APP-Transgenic Mice for Glutaminyl Cyclase as Drug Target to Diminish pE-Abeta Formation. Molecules 2018; 23:molecules23040924. [PMID: 29673150 PMCID: PMC6017857 DOI: 10.3390/molecules23040924] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/05/2018] [Accepted: 04/10/2018] [Indexed: 02/06/2023] Open
Abstract
Oligomeric assemblies of neurotoxic amyloid beta (Abeta) peptides generated by proteolytical processing of the amyloid precursor protein (APP) play a key role in the pathogenesis of Alzheimer’s disease (AD). In recent years, a substantial heterogeneity of Abeta peptides with distinct biophysical and cell biological properties has been demonstrated. Among these, a particularly neurotoxic and disease-specific Abeta variant is N-terminally truncated and modified to pyroglutamate (pE-Abeta). Cell biological and animal experimental studies imply the catalysis of this modification by the enzyme glutaminyl cyclase (QC). However, direct histopathological evidence in transgenic animals from comparative brain region and cell type-specific expression of transgenic hAPP and QC, on the one hand, and on the formation of pE-Abeta aggregates, on the other, is lacking. Here, using single light microscopic, as well as triple immunofluorescent, labeling, we report the deposition of pE-Abeta only in the brain regions of APP-transgenic Tg2576 mice with detectable human APP and endogenous QC expression, such as the hippocampus, piriform cortex, and amygdala. Brain regions showing human APP expression without the concomitant presence of QC (the anterodorsal thalamic nucleus and perifornical nucleus) do not display pE-Abeta plaque formation. However, we also identified brain regions with substantial expression of human APP and QC in the absence of pE-Abeta deposition (the Edinger-Westphal nucleus and locus coeruleus). In these brain regions, the enzymes required to generate N-truncated Abeta peptides as substrates for QC might be lacking. Our observations provide additional evidence for an involvement of QC in AD pathogenesis via QC-catalyzed pE-Abeta formation.
Collapse
Affiliation(s)
| | - Alexandra Bluhm
- Paul Flechsig Institute for Brain Research, University of Leipzig, 04103 Leipzig, Germany.
| | - Anke Piechotta
- Department of Molecular Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, 06120 Halle (Saale), Germany.
| | - Miriam Linnert
- Department of Molecular Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, 06120 Halle (Saale), Germany.
| | - Jens-Ulrich Rahfeld
- Department of Molecular Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, 06120 Halle (Saale), Germany.
| | - Hans-Ulrich Demuth
- Department of Molecular Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, 06120 Halle (Saale), Germany.
| | - Inge Lues
- Probiodrug AG, 06120 Halle (Saale), Germany.
| | - Peer-Hendrik Kuhn
- Institute of Pathology, Technical University of Munich, 81675 Munich, Germany.
| | - Stefan F Lichtenthaler
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), 81377 Munich, Germany.
- Munich Cluster of Systems Neurology (SyNergy), 81377 Munich, Germany.
- Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany.
- Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany.
| | - Steffen Roßner
- Paul Flechsig Institute for Brain Research, University of Leipzig, 04103 Leipzig, Germany.
| | - Corinna Höfling
- Paul Flechsig Institute for Brain Research, University of Leipzig, 04103 Leipzig, Germany.
| |
Collapse
|
23
|
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
| |
Collapse
|
24
|
Toombs J, Foiani MS, Wellington H, Paterson RW, Arber C, Heslegrave A, Lunn MP, Schott JM, Wray S, Zetterberg H. Amyloid β peptides are differentially vulnerable to preanalytical surface exposure, an effect incompletely mitigated by the use of ratios. ALZHEIMER'S & DEMENTIA: DIAGNOSIS, ASSESSMENT & DISEASE MONITORING 2018; 10:311-321. [PMID: 29780875 PMCID: PMC5956932 DOI: 10.1016/j.dadm.2018.02.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Introduction We tested the hypothesis that the amyloid β (Aβ) peptide ratios are more stable than Aβ42 alone when biofluids are exposed to two preanalytical conditions known to modify measurable Aβ concentration. Methods Human cerebrospinal fluid (CSF) and culture media (CM) from human cortical neurons were exposed to a series of volumes and polypropylene surfaces. Aβ42, Aβ40, and Aβ38 peptide concentrations were measured using a multiplexed electrochemiluminescence immunoassay. Data were analyzed using mixed models in R. Results Decrease of measurable Aβ peptide concentrations was exaggerated in longer peptides, affecting the Aβ42:Aβ40 and Aβ42:Aβ38 ratios. However, the effect size of surface treatment was reduced in Aβ peptide ratios versus Aβ42 alone. For Aβ42:Aβ40, the effect was reduced by approximately 50% (volume) and 75% (transfer) as compared to Aβ42 alone. Discussion Use of Aβ ratios, in conjunction with concentrations, may mitigate confounding factors and assist the clinical diagnostic process for Alzheimer's disease.
Collapse
Affiliation(s)
- Jamie Toombs
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
| | - Martha S Foiani
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
| | - Henrietta Wellington
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
| | - Ross W Paterson
- Department of Neurodegeneration, Dementia Research Centre, Institute of Neurology, London, UK
| | - Charles Arber
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
| | - Amanda Heslegrave
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
| | - Michael P Lunn
- Department of Neuroimmunology, Institute of Neurology, University College London, London, UK
| | - Jonathan M Schott
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
| | - Selina Wray
- Department of Neurodegeneration, Dementia Research Centre, Institute of Neurology, London, UK
| | - Henrik Zetterberg
- Department of Molecular Neuroscience, University College London, London, UK.,UK Dementia Research Institute, London, UK.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| |
Collapse
|
25
|
Shinohara M, Koga S, Konno T, Nix J, Shinohara M, Aoki N, Das P, Parisi JE, Petersen RC, Rosenberry TL, Dickson DW, Bu G. Distinct spatiotemporal accumulation of N-truncated and full-length amyloid-β42 in Alzheimer's disease. Brain 2017; 140:3301-3316. [PMID: 29161341 PMCID: PMC5841214 DOI: 10.1093/brain/awx284] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 09/02/2017] [Accepted: 09/11/2017] [Indexed: 01/22/2023] Open
Abstract
Accumulation of amyloid-β peptides is a dominant feature in the pathogenesis of Alzheimer's disease; however, it is not clear how individual amyloid-β species accumulate and affect other neuropathological and clinical features in the disease. Thus, we compared the accumulation of N-terminally truncated amyloid-β and full-length amyloid-β, depending on disease stage as well as brain area, and determined how these amyloid-β species respectively correlate with clinicopathological features of Alzheimer's disease. To this end, the amounts of amyloid-β species and other proteins related to amyloid-β metabolism or Alzheimer's disease were quantified by enzyme-linked immunosorbent assays (ELISA) or theoretically calculated in 12 brain regions, including neocortical, limbic and subcortical areas from Alzheimer's disease cases (n = 19), neurologically normal elderly without amyloid-β accumulation (normal ageing, n = 13), and neurologically normal elderly with cortical amyloid-β accumulation (pathological ageing, n = 15). We observed that N-terminally truncated amyloid-β42 and full-length amyloid-β42 accumulations distributed differently across disease stages and brain areas, while N-terminally truncated amyloid-β40 and full-length amyloid-β40 accumulation showed an almost identical distribution pattern. Cortical N-terminally truncated amyloid-β42 accumulation was increased in Alzheimer's disease compared to pathological ageing, whereas cortical full-length amyloid-β42 accumulation was comparable between Alzheimer's disease and pathological ageing. Moreover, N-terminally truncated amyloid-β42 were more likely to accumulate more in specific brain areas, especially some limbic areas, while full-length amyloid-β42 tended to accumulate more in several neocortical areas, including frontal cortices. Immunoprecipitation followed by mass spectrometry analysis showed that several N-terminally truncated amyloid-β42 species, represented by pyroglutamylated amyloid-β11-42, were enriched in these areas, consistent with ELISA results. N-terminally truncated amyloid-β42 accumulation showed significant regional association with BACE1 and neprilysin, but not PSD95 that regionally associated with full-length amyloid-β42 accumulation. Interestingly, accumulations of tau and to a greater extent apolipoprotein E (apoE, encoded by APOE) were more strongly correlated with N-terminally truncated amyloid-β42 accumulation than those of other amyloid-β species across brain areas and disease stages. Consistently, immunohistochemical staining and in vitro binding assays showed that apoE co-localized and bound more strongly with pyroglutamylated amyloid-β11-x fibrils than full-length amyloid-β fibrils. Retrospective review of clinical records showed that accumulation of N-terminally truncated amyloid-β42 in cortical areas was associated with disease onset, duration and cognitive scores. Collectively, N-terminally truncated amyloid-β42 species have spatiotemporal accumulation patterns distinct from full-length amyloid-β42, likely due to different mechanisms governing their accumulations in the brain. These truncated amyloid-β species could play critical roles in the disease by linking other clinicopathological features of Alzheimer's disease.
Collapse
Affiliation(s)
| | - Shunsuke Koga
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Takuya Konno
- Department of Neurology, Mayo Clinic, Jacksonville, FL, USA
| | - Jeremy Nix
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | - Naoya Aoki
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Pritam Das
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Joseph E Parisi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | | | | | | | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| |
Collapse
|
26
|
Frost GR, Li YM. The role of astrocytes in amyloid production and Alzheimer's disease. Open Biol 2017; 7:170228. [PMID: 29237809 PMCID: PMC5746550 DOI: 10.1098/rsob.170228] [Citation(s) in RCA: 228] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/16/2017] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is marked by the presence of extracellular amyloid beta (Aβ) plaques, intracellular neurofibrillary tangles (NFTs) and gliosis, activated glial cells, in the brain. It is thought that Aβ plaques trigger NFT formation, neuronal cell death, neuroinflammation and gliosis and, ultimately, cognitive impairment. There are increased numbers of reactive astrocytes in AD, which surround amyloid plaques and secrete proinflammatory factors and can phagocytize and break down Aβ. It was thought that neuronal cells were the major source of Aβ. However, mounting evidence suggests that astrocytes may play an additional role in AD by secreting significant quantities of Aβ and contributing to overall amyloid burden in the brain. Astrocytes are the most numerous cell type in the brain, and therefore even minor quantities of amyloid secretion from individual astrocytes could prove to be substantial when taken across the whole brain. Reactive astrocytes have increased levels of the three necessary components for Aβ production: amyloid precursor protein, β-secretase (BACE1) and γ-secretase. The identification of environmental factors, such as neuroinflammation, that promote astrocytic Aβ production, could redefine how we think about developing therapeutics for AD.
Collapse
Affiliation(s)
- Georgia R Frost
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Programs of Neurosciences, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, USA
| | - Yue-Ming Li
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Programs of Neurosciences, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, USA
- Pharmacology, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, USA
| |
Collapse
|
27
|
Grimm MOW, Michaelson DM, Hartmann T. Omega-3 fatty acids, lipids, and apoE lipidation in Alzheimer's disease: a rationale for multi-nutrient dementia prevention. J Lipid Res 2017; 58:2083-2101. [PMID: 28528321 PMCID: PMC5665674 DOI: 10.1194/jlr.r076331] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/09/2017] [Indexed: 12/14/2022] Open
Abstract
In the last decade, it has become obvious that Alzheimer's disease (AD) is closely linked to changes in lipids or lipid metabolism. One of the main pathological hallmarks of AD is amyloid-β (Aβ) deposition. Aβ is derived from sequential proteolytic processing of the amyloid precursor protein (APP). Interestingly, both, the APP and all APP secretases are transmembrane proteins that cleave APP close to and in the lipid bilayer. Moreover, apoE4 has been identified as the most prevalent genetic risk factor for AD. ApoE is the main lipoprotein in the brain, which has an abundant role in the transport of lipids and brain lipid metabolism. Several lipidomic approaches revealed changes in the lipid levels of cerebrospinal fluid or in post mortem AD brains. Here, we review the impact of apoE and lipids in AD, focusing on the major brain lipid classes, sphingomyelin, plasmalogens, gangliosides, sulfatides, DHA, and EPA, as well as on lipid signaling molecules, like ceramide and sphingosine-1-phosphate. As nutritional approaches showed limited beneficial effects in clinical studies, the opportunities of combining different supplements in multi-nutritional approaches are discussed and summarized.
Collapse
Affiliation(s)
- Marcus O W Grimm
- Department of Experimental Neurology and Department of Neurodegeneration and Neurobiology, and Deutsches Institut für DemenzPrävention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Daniel M Michaelson
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Tobias Hartmann
- Department of Experimental Neurology and Department of Neurodegeneration and Neurobiology, and Deutsches Institut für DemenzPrävention (DIDP), Saarland University, Homburg/Saar, Germany
| |
Collapse
|
28
|
Diversity of Amyloid-beta Proteoforms in the Alzheimer's Disease Brain. Sci Rep 2017; 7:9520. [PMID: 28842697 PMCID: PMC5572664 DOI: 10.1038/s41598-017-10422-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/08/2017] [Indexed: 12/31/2022] Open
Abstract
Amyloid-beta (Aβ) plays a key role in the pathogenesis of Alzheimer’s disease (AD), but little is known about the proteoforms present in AD brain. We used high-resolution mass spectrometry to analyze intact Aβ from soluble aggregates and insoluble material in brains of six cases with severe dementia and pathologically confirmed AD. The soluble aggregates are especially relevant because they are believed to be the most toxic form of Aβ. We found a diversity of Aβ peptides, with 26 unique proteoforms including various N- and C-terminal truncations. N- and C-terminal truncations comprised 73% and 30%, respectively, of the total Aβ proteoforms detected. The Aβ proteoforms segregated between the soluble and more insoluble aggregates with N-terminal truncations predominating in the insoluble material and C- terminal truncations segregating into the soluble aggregates. In contrast, canonical Aβ comprised the minority of the identified proteoforms (15.3%) and did not distinguish between the soluble and more insoluble aggregates. The relative abundance of many truncated Aβ proteoforms did not correlate with post-mortem interval, suggesting they are not artefacts. This heterogeneity of Aβ proteoforms deepens our understanding of AD and offers many new avenues for investigation into pathological mechanisms of the disease, with implications for therapeutic development.
Collapse
|
29
|
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.
Collapse
Affiliation(s)
- Simon C. Drew
- Department of Medicine, Royal Melbourne Hospital, University of MelbourneMelbourne, VIC, Australia
| |
Collapse
|
30
|
Mehta PD, Blain JF, Freeman EA, Patrick BA, Barshatzky M, Hrdlicka LA, Mehta SP, Frackowiak J, Mazur-Kolecka B, Wegiel J, Patzke H, Miller DL. Generation and Partial Characterization of Rabbit Monoclonal Antibody to Amyloid-β Peptide 1-37 (Aβ37). J Alzheimers Dis 2017; 57:135-145. [PMID: 28222530 DOI: 10.3233/jad-161207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Secreted soluble amyloid-β 1-37 (Aβ37) peptide is one of the prominent Aβ forms next to Aβ40, and is found in cerebrospinal fluid (CSF) and blood. Recent studies have shown the importance of quantitation of CSF Aβ37 levels in combination with Aβ38, Aβ40, and Aβ42 to support the diagnosis of patients with probable Alzheimer's disease (AD), and the value of antibody to Aβ37 to facilitate drug discovery studies. However, the availability of reliable and specific monoclonal antibody to Aβ37 is very limited. Our aims were: 1) to generate and partially characterize rabbit monoclonal antibody (RabmAb) to Aβ37, and 2) to determine whether the antibody detects changes in Aβ37 levels produced by a γ-secretase modulator (GSM). Our generated RabmAb to Aβ37 was found to be specific to Aβ37, since it did not react with Aβ36, Aβ38, Aβ39, Aβ40, and Aβ42 in an ELISA or immunoblotting. The epitope of the antibody was contained in the seven C-terminal residues of Aβ37. The antibody was sensitive enough to measure CSF and plasma Aβ37 levels in ELISA. Immunohistological studies showed the presence of Aβ37-positive deposits in the brain of AD, and Down syndrome persons diagnosed with AD. Our studies also showed that the antibody detected Aβ37 increases in CSF and brains of rodents following treatment with a GSM. Thus, our antibody can be widely applied to AD research, and in a panel based approach it may have potential to support the diagnosis of probable AD, and in testing the effect of GSMs to target AD.
Collapse
Affiliation(s)
- Pankaj D Mehta
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | | | | | - Bruce A Patrick
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | - Marc Barshatzky
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | | | - Sangita P Mehta
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | - Janusz Frackowiak
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | - Bozena Mazur-Kolecka
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | - Jerzy Wegiel
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| | | | - David L Miller
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY, USA
| |
Collapse
|
31
|
Becker-Pauly C, Pietrzik CU. The Metalloprotease Meprin β Is an Alternative β-Secretase of APP. Front Mol Neurosci 2017; 9:159. [PMID: 28105004 PMCID: PMC5215381 DOI: 10.3389/fnmol.2016.00159] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 12/09/2016] [Indexed: 01/08/2023] Open
Abstract
The membrane bound metalloprotease meprin β is important for collagen fibril assembly in connective tissue formation and for the detachment of the intestinal mucus layer for proper barrier function. Recent proteomic studies revealed dozens of putative new substrates of meprin β, including the amyloid precursor protein (APP). It was shown that APP is cleaved by meprin β in distinct ways, either at the β-secretase site resulting in increased levels of Aβ peptides, or at the N-terminus releasing 11 kDa, and 20 kDa peptide fragments. The latter event was discussed to be rather neuroprotective, whereas the ectodomain shedding of APP by meprin β reminiscent to BACE-1 is in line with the amyloid hypothesis of Alzheimer's disease, promoting neurodegeneration. The N-terminal 11 kDa and 20 kDa peptide fragments represent physiological cleavage products, since they are found in human brains under different diseased or non-diseased states, whereas these fragments are completely missing in brains of meprin β knock-out animals. Meprin β is not only a sheddase of adhesion molecules, such as APP, but was additionally demonstrated to cleave within the prodomain of ADAM10. Activated ADAM10, the α-secretase of APP, is then able to shed meprin β from the cell surface thereby abolishing the β-secretase activity. All together meprin β seems to be a novel player in APP processing events, even influencing other enzymes involved in APP cleavage.
Collapse
Affiliation(s)
- Christoph Becker-Pauly
- Unit for Degradomics of the Protease Web, Institute of Biochemistry, University of Kiel Kiel, Germany
| | - Claus U Pietrzik
- Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University Mainz Mainz, Germany
| |
Collapse
|
32
|
Breydo L, Redington JM, Uversky VN. Effects of Intrinsic and Extrinsic Factors on Aggregation of Physiologically Important Intrinsically Disordered Proteins. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 329:145-185. [PMID: 28109327 DOI: 10.1016/bs.ircmb.2016.08.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Misfolding and aggregation of proteins and peptides play an important role in a number of diseases as well as in many physiological processes. Many of the proteins that misfold and aggregate in vivo are intrinsically disordered. Protein aggregation is a complex multistep process, and aggregates can significantly differ in morphology, structure, stability, cytotoxicity, and self-propagation ability. The aggregation process is influenced by both intrinsic (e.g., mutations and expression levels) and extrinsic (e.g., polypeptide chain truncation, macromolecular crowding, posttranslational modifications, as well as interaction with metal ions, other small molecules, lipid membranes, and chaperons) factors. This review examines the effect of a variety of these factors on aggregation of physiologically important intrinsically disordered proteins.
Collapse
Affiliation(s)
- L Breydo
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States.
| | - J M Redington
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - V N Uversky
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
| |
Collapse
|
33
|
Savastano A, Klafki H, Haußmann U, Oberstein TJ, Muller P, Wirths O, Wiltfang J, Bayer TA. N-truncated Aβ2-X starting with position two in sporadic Alzheimer's disease cases and two Alzheimer mouse models. J Alzheimers Dis 2016; 49:101-10. [PMID: 26529393 DOI: 10.3233/jad-150394] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
According to the modified amyloid hypothesis, the key event in the pathogenesis of Alzheimer's disease (AD) is the deposition of neurotoxic amyloid β-peptides (Aβs) in plaques and cerebral blood vessels. Additionally to full-length peptides, a great diversity of N-truncated Aβ variants is derived from the larger amyloid-β protein precursor (AβPP). Vast evidence suggests that Aβx-42 isoforms play an important role in triggering neurodegeneration due to their high abundance, amyloidogenic propensity and toxicity. Although N-truncated Aβ peptides and Aβx-42 species appear to be the crucial players in AD etiology, the Aβ2-X isoforms did not receive much attention yet. The present study is the first to show immunohistochemical evidence of Aβ2-X in cases of AD and its distribution in AβPP/PS1KI and 5XFAD transgenic mouse models using a novel antibody pAB77 that has been developed using Aβ2-14 as antigen. Positive plaques and congophilic amyloid angiopathy (CAA) were observed in AD cases and in both mouse models. While in AD cases, abundant CAA and less pronounced plaque pathology was evident, the two mouse models showed predominantly extracellular Aβ deposits and minor CAA staining. Western blotting and a capillary isoelectric focusing immunoassay demonstrated the high specificity of the antibody pAb77 against Aβ-variants starting with the N-terminal Alanine-2.
Collapse
Affiliation(s)
- Adriana Savastano
- Georg-August-University Göttingen, University Medicine Göttingen, Department of Psychiatry and Psychotherapy, Göttingen, Germany
| | - Hans Klafki
- Georg-August-University Göttingen, University Medicine Göttingen, Department of Psychiatry and Psychotherapy, Göttingen, Germany.,LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - Ute Haußmann
- LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - Timo Jan Oberstein
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Petr Muller
- Moravian Biotechnology, Brno, Czech Republic
| | - Oliver Wirths
- Georg-August-University Göttingen, University Medicine Göttingen, Department of Psychiatry and Psychotherapy, Göttingen, Germany
| | - Jens Wiltfang
- Georg-August-University Göttingen, University Medicine Göttingen, Department of Psychiatry and Psychotherapy, Göttingen, Germany
| | - Thomas A Bayer
- Georg-August-University Göttingen, University Medicine Göttingen, Department of Psychiatry and Psychotherapy, Göttingen, Germany
| |
Collapse
|
34
|
Beyer I, Rezaei-Ghaleh N, Klafki HW, Jahn O, Haußmann U, Wiltfang J, Zweckstetter M, Knölker HJ. Solid-Phase Synthesis and Characterization of N-Terminally Elongated Aβ-3-x -Peptides. Chemistry 2016; 22:8685-93. [PMID: 27167300 PMCID: PMC5084751 DOI: 10.1002/chem.201600892] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Indexed: 01/24/2023]
Abstract
In addition to the prototypic amyloid-β (Aβ) peptides Aβ1-40 and Aβ1-42 , several Aβ variants differing in their amino and carboxy termini have been described. Synthetic availability of an Aβ variant is often the key to study its role under physiological or pathological conditions. Herein, we report a protocol for the efficient solid-phase peptide synthesis of the N-terminally elongated Aβ-peptides Aβ-3-38 , Aβ-3-40 , and Aβ-3-42 . Biophysical characterization by NMR spectroscopy, CD spectroscopy, an aggregation assay, and electron microscopy revealed that all three peptides were prone to aggregation into amyloid fibrils. Immunoprecipitation, followed by mass spectrometry, indicated that Aβ-3-38 and Aβ-3-40 are generated by transfected cells even in the presence of a tripartite β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitor. The elongated Aβ peptides starting at Val(-3) can be separated from N-terminally-truncated Aβ forms by high-resolution isoelectric-focusing techniques, despite virtually identical isoelectric points. The synthetic Aβ variants and the methods presented here are providing tools to advance our understanding of the potential roles of N-terminally elongated Aβ variants in Alzheimer's disease.
Collapse
Affiliation(s)
- Isaak Beyer
- Department Chemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
| | - Nasrollah Rezaei-Ghaleh
- Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Hans-Wolfgang Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-Universität, 37075, Göttingen, Germany
| | - Olaf Jahn
- Max Planck Institute for Experimental Medicine, Proteomics Group, 37075, Göttingen, Germany
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, University of Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Ute Haußmann
- University of Duisburg-Essen, 45141, Essen, Germany
| | - Jens Wiltfang
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany. ,
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-Universität, 37075, Göttingen, Germany. ,
| | - Markus Zweckstetter
- Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, University of Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Hans-Joachim Knölker
- Department Chemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany.
| |
Collapse
|
35
|
Nagel-Steger L, Owen MC, Strodel B. An Account of Amyloid Oligomers: Facts and Figures Obtained from Experiments and Simulations. Chembiochem 2016; 17:657-76. [PMID: 26910367 DOI: 10.1002/cbic.201500623] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Indexed: 12/27/2022]
Abstract
The deposition of amyloid in brain tissue in the context of neurodegenerative diseases involves the formation of intermediate species-termed oligomers-of lower molecular mass and with structures that deviate from those of mature amyloid fibrils. Because these oligomers are thought to be primarily responsible for the subsequent disease pathogenesis, the elucidation of their structure is of enormous interest. Nevertheless, because of the high aggregation propensity and the polydispersity of oligomeric species formed by the proteins or peptides in question, the preparation of appropriate samples for high-resolution structural methods has proven to be rather difficult. This is why theoretical approaches have been of particular importance in gaining insights into possible oligomeric structures for some time. Only recently has it been possible to achieve some progress with regard to the experimentally based structural characterization of defined oligomeric species. Here we discuss how theory and experiment are used to determine oligomer structures and what can be done to improve the integration of the two disciplines.
Collapse
Affiliation(s)
- Luitgard Nagel-Steger
- Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany.,Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätstrasse 1, 40225, Düsseldorf, Germany
| | - Michael C Owen
- Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Birgit Strodel
- Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany. .,Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Universitätstrasse 1, 40225, Düsseldorf, Germany.
| |
Collapse
|
36
|
Immunotherapy Against N-Truncated Amyloid-β Oligomers. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2016. [DOI: 10.1007/978-1-4939-3560-4_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
|
37
|
Frost JL, Liu B, Rahfeld JU, Kleinschmidt M, O'Nuallain B, Le KX, Lues I, Caldarone BJ, Schilling S, Demuth HU, Lemere CA. An anti-pyroglutamate-3 Aβ vaccine reduces plaques and improves cognition in APPswe/PS1ΔE9 mice. Neurobiol Aging 2015; 36:3187-3199. [PMID: 26453001 DOI: 10.1016/j.neurobiolaging.2015.08.021] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 07/10/2015] [Accepted: 08/22/2015] [Indexed: 10/23/2022]
Abstract
Pyroglutamate-3 amyloid-beta (pGlu-3 Aβ) is an N-terminally truncated Aβ isoform likely playing a decisive role in Alzheimer's disease pathogenesis. Here, we describe a prophylactic passive immunization study in APPswe/PS1ΔE9 mice using a novel pGlu-3 Aβ immunoglobulin G1 (IgG1) monoclonal antibody, 07/1 (150 and 500 μg, intraperitoneal, weekly) and compare its efficacy with a general Aβ IgG1 monoclonal antibody, 3A1 (200 μg, intraperitoneal, weekly) as a positive control. After 28 weeks of treatment, plaque burden was reduced and cognitive performance of 07/1-immunized Tg mice, especially at the higher dose, was normalized to wild-type levels in 2 hippocampal-dependent tests and partially spared compared with phosphate-buffered saline-treated Tg mice. Mice that received 3A1 had reduced plaque burden but showed no cognitive benefit. In contrast with 3A1, treatment with 07/1 did not increase the concentration of Aβ in plasma, suggesting different modes of Aβ plaque clearance. In conclusion, early selective targeting of pGlu-3 Aβ by immunotherapy may be effective in lowering cerebral Aβ plaque burden and preventing cognitive decline in the clinical setting. Targeting this pathologically modified form of Aβ thereby is unlikely to interfere with potential physiologic function(s) of Aβ that have been proposed.
Collapse
Affiliation(s)
- Jeffrey L Frost
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Bin Liu
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | | | | | - Brian O'Nuallain
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Kevin X Le
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Inge Lues
- Probiodrug AG, Halle (Saale), Germany
| | - Barbara J Caldarone
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Harvard NeuroDiscovery Center NeuroBehavior Laboratory Core, Harvard Institutes of Medicine, Boston, MA, USA
| | | | | | - Cynthia A Lemere
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
38
|
Grimm MOW, Mett J, Stahlmann CP, Grösgen S, Haupenthal VJ, Blümel T, Hundsdörfer B, Zimmer VC, Mylonas NT, Tanila H, Müller U, Grimm HS, Hartmann T. APP intracellular domain derived from amyloidogenic β- and γ-secretase cleavage regulates neprilysin expression. Front Aging Neurosci 2015; 7:77. [PMID: 26074811 PMCID: PMC4443740 DOI: 10.3389/fnagi.2015.00077] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/24/2015] [Indexed: 01/30/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by an accumulation of Amyloid-β (Aβ), released by sequential proteolytic processing of the amyloid precursor protein (APP) by β - and γ-secretase. Aβ peptides can aggregate, leading to toxic Aβ oligomers and amyloid plaque formation. Aβ accumulation is not only dependent on de novo synthesis but also on Aβ degradation. Neprilysin (NEP) is one of the major enzymes involved in Aβ degradation. Here we investigate the molecular mechanism of NEP regulation, which is up to now controversially discussed to be affected by APP processing itself. We found that NEP expression is highly dependent on the APP intracellular domain (AICD), released by APP processing. Mouse embryonic fibroblasts devoid of APP processing, either by the lack of the catalytically active subunit of the γ-secretase complex [presenilin (PS) 1/2] or by the lack of APP and the APP-like protein 2 (APLP2), showed a decreased NEP expression, activity and protein level. Similar results were obtained by utilizing cells lacking a functional AICD domain (APPΔCT15) or expressing mutations in the genes encoding for PS1. AICD supplementation or retransfection with an AICD encoding plasmid could rescue the down-regulation of NEP further strengthening the link between AICD and transcriptional NEP regulation, in which Fe65 acts as an important adaptor protein. Especially AICD generated by the amyloidogenic pathway seems to be more involved in the regulation of NEP expression. In line, analysis of NEP gene expression in vivo in six transgenic AD mouse models (APP and APLP2 single knock-outs, APP/APLP2 double knock-out, APP-swedish, APP-swedish/PS1Δexon9, and APPΔCT15) confirmed the results obtained in cell culture. In summary, in the present study we clearly demonstrate an AICD-dependent regulation of the Aβ-degrading enzyme NEP in vitro and in vivo and elucidate the underlying mechanisms that might be beneficial to develop new therapeutic strategies for the treatment of AD.
Collapse
Affiliation(s)
- Marcus O W Grimm
- Department of Experimental Neurology, Saarland University Homburg, Germany ; Department of Neurodegeneration and Neurobiology, Saarland University Homburg, Germany ; Deutsches Institut für DemenzPrävention, Saarland University Homburg, Germany
| | - Janine Mett
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | | | - Sven Grösgen
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | - Viola J Haupenthal
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | - Tamara Blümel
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | | | - Valerie C Zimmer
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | - Nadine T Mylonas
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | - Heikki Tanila
- Department of Neurobiology, A.I. Virtanen Institute, University of Eastern Finland Kuopio, Finland ; Department of Neurology, Kuopio University Hospital Kuopio, Finland
| | - Ulrike Müller
- Department of Functional Genomics, Institute for Pharmacy and Molecular Biotechnology, Heidelberg University Heidelberg, Germany
| | - Heike S Grimm
- Department of Experimental Neurology, Saarland University Homburg, Germany
| | - Tobias Hartmann
- Department of Experimental Neurology, Saarland University Homburg, Germany ; Department of Neurodegeneration and Neurobiology, Saarland University Homburg, Germany ; Deutsches Institut für DemenzPrävention, Saarland University Homburg, Germany
| |
Collapse
|
39
|
Oberstein TJ, Spitzer P, Klafki HW, Linning P, Neff F, Knölker HJ, Lewczuk P, Wiltfang J, Kornhuber J, Maler JM. Astrocytes and microglia but not neurons preferentially generate N-terminally truncated Aβ peptides. Neurobiol Dis 2015; 73:24-35. [DOI: 10.1016/j.nbd.2014.08.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 08/05/2014] [Accepted: 08/31/2014] [Indexed: 12/30/2022] Open
|
40
|
Kummer MP, Heneka MT. Truncated and modified amyloid-beta species. ALZHEIMERS RESEARCH & THERAPY 2014; 6:28. [PMID: 25031638 PMCID: PMC4055046 DOI: 10.1186/alzrt258] [Citation(s) in RCA: 211] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer’s disease pathology is closely connected to the processing of the amyloid precursor protein (APP) resulting in the formation of a variety of amyloid-beta (Aβ) peptides. They are found as insoluble aggregates in senile plaques, the histopathological hallmark of the disease. These peptides are also found in soluble, mostly monomeric and dimeric, forms in the interstitial and cerebrospinal fluid. Due to the combination of several enzymatic activities during APP processing, Aβ peptides exist in multiple isoforms possessing different N-termini and C-termini. These peptides include, to a certain extent, part of the juxtamembrane and transmembrane domain of APP. Besides differences in size, post-translational modifications of Aβ – including oxidation, phosphorylation, nitration, racemization, isomerization, pyroglutamylation, and glycosylation – generate a plethora of peptides with different physiological and pathological properties that may modulate disease progression.
Collapse
Affiliation(s)
- Markus P Kummer
- Department of Neurology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
| | - Michael T Heneka
- Department of Neurology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany ; German Center for Neurodegenerative Diseases (DZNE), Holbeinstrasse 15, 53117 Bonn, Germany
| |
Collapse
|
41
|
Focusing the amyloid cascade hypothesis on N-truncated Abeta peptides as drug targets against Alzheimer's disease. Acta Neuropathol 2014; 127:787-801. [PMID: 24803226 PMCID: PMC4024135 DOI: 10.1007/s00401-014-1287-x] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 04/25/2014] [Accepted: 04/25/2014] [Indexed: 02/07/2023]
Abstract
Although N-truncated Aβ variants are known to be the main constituent of amyloid plaques in the brains of patients with Alzheimer’s disease, their potential as targets for pharmacological intervention has only recently been investigated. In the last few years, the Alzheimer field has experienced a paradigm shift with the ever increasing understanding that targeting amyloid plaques has not led to a successful immunotherapy. On the other hand, there can be no doubt that the amyloid cascade hypothesis is central to the etiology of Alzheimer’s disease, raising the question as to why it is apparently failing to translate into the clinic. In this review, we aim to refocus the amyloid hypothesis integrating N-truncated Aβ peptides based on mounting evidence that they may represent better targets than full-length Aβ. In addition to Aβ peptides starting with an Asp at position 1, a variety of different N-truncated Aβ peptides have been identified starting with amino residue Ala-2, pyroglutamylated Glu-3, Phe-4, Arg-5, His-6, Asp-7, Ser-8, Gly-9, Tyr-10 and pyroglutamylated Glu-11. Certain forms of N-truncated species are better correlates for early pathological changes found pre-symptomatically more often than others. There is also evidence that, together with full-length Aβ, they might be physiologically detectable and are naturally secreted by neurons. Others are known to form soluble aggregates, which have neurotoxic properties in transgenic mouse models. It has been clearly demonstrated by several groups that some N-truncated Aβs dominate full-length Aβ in the brains of Alzheimer’s patients. We try to address which of the N-truncated variants may be promising therapeutic targets and which enzymes might be involved in the generation of these peptides
Collapse
|
42
|
de Rivero Vaccari JP, Brand FJ, Sedaghat C, Mash DC, Dietrich WD, Keane RW. RIG-1 receptor expression in the pathology of Alzheimer's disease. J Neuroinflammation 2014; 11:67. [PMID: 24694234 PMCID: PMC3977677 DOI: 10.1186/1742-2094-11-67] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 03/25/2014] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Neuroinflammation plays a critical role in the pathogenesis of Alzheimer's disease (AD) and involves activation of the innate immune response via recognition of diverse stimuli by pattern recognition receptors (PRRs). The inflammatory inducers and precise innate signaling pathway contributing to AD pathology remain largely undefined. RESULTS In the present study we analyzed expression levels of innate immune proteins in temporal and occipital cortices from preclinical (no cognitive impairment, NCI, N = 22) to mild cognitive impairment (MCI, N = 20) associated with AD pathology (N = 20) and AD patients (N = 23). We found that retinoic acid-inducible gene-I (RIG-1) is significantly elevated in the temporal cortex and plasma in patients with MCI. In addition, primary human astrocytes stimulated with the RIG-1 ligand 5'ppp RNA showed increased expression of amyloid precursor protein (APP) and amyloid-β (Aβ), supporting the idea that RIG-1 is involved in the pathology of MCI associated with early progression to AD. CONCLUSION These findings suggest that RIG-1 may play a critical role in incipient AD.
Collapse
Affiliation(s)
- Juan Pablo de Rivero Vaccari
- Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Frank J Brand
- Department of Physiology & Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Christina Sedaghat
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Deborah C Mash
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - W Dalton Dietrich
- Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Robert W Keane
- Department of Physiology & Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| |
Collapse
|
43
|
PDK1 decreases TACE-mediated α-secretase activity and promotes disease progression in prion and Alzheimer's diseases. Nat Med 2013; 19:1124-31. [DOI: 10.1038/nm.3302] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 07/16/2013] [Indexed: 12/17/2022]
|
44
|
Haußmann U, Jahn O, Linning P, Janßen C, Liepold T, Portelius E, Zetterberg H, Bauer C, Schuchhardt J, Knölker HJ, Klafki H, Wiltfang J. Analysis of Amino-Terminal Variants of Amyloid-β Peptides by Capillary Isoelectric Focusing Immunoassay. Anal Chem 2013; 85:8142-9. [DOI: 10.1021/ac401055y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ute Haußmann
- LVR-Klinikum Essen, Department
of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, D-45147 Essen, Germany
| | - Olaf Jahn
- Max-Planck-Institute of Experimental Medicine, Proteomics Group, D-37075
Göttingen, Germany
| | - Philipp Linning
- Department of Chemistry, Technische Universität Dresden, D-01069 Dresden,
Germany
| | - Christin Janßen
- LVR-Klinikum Essen, Department
of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, D-45147 Essen, Germany
| | - Thomas Liepold
- Max-Planck-Institute of Experimental Medicine, Proteomics Group, D-37075
Göttingen, Germany
| | - Erik Portelius
- Department of Psychiatry
and
Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska
Academy, University of Gothenburg, 431
80 Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry
and
Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska
Academy, University of Gothenburg, 431
80 Mölndal, Sweden
- UCL Institute of Neurology, Queen Square, London, U.K
| | - Chris Bauer
- MicroDiscovery GmbH, D-10405 Berlin, Germany
| | | | - Hans-Joachim Knölker
- Department of Chemistry, Technische Universität Dresden, D-01069 Dresden,
Germany
| | - Hans Klafki
- LVR-Klinikum Essen, Department
of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, D-45147 Essen, Germany
| | - Jens Wiltfang
- LVR-Klinikum Essen, Department
of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, D-45147 Essen, Germany
| |
Collapse
|
45
|
Yamashima T. Reconsider Alzheimer's disease by the 'calpain-cathepsin hypothesis'--a perspective review. Prog Neurobiol 2013; 105:1-23. [PMID: 23499711 DOI: 10.1016/j.pneurobio.2013.02.004] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 02/08/2013] [Accepted: 02/28/2013] [Indexed: 01/24/2023]
Abstract
Alzheimer's disease (AD) is characterized by slowly progressive neuronal death, but its molecular cascade remains elusive for over 100 years. Since accumulation of autophagic vacuoles (also called granulo-vacuolar degenerations) represents one of the pathologic hallmarks of degenerating neurons in AD, a causative connection between autophagy failure and neuronal death should be present. The aim of this perspective review is at considering such underlying mechanism of AD that age-dependent oxidative stresses may affect the autophagic-lysosomal system via carbonylation and cleavage of heat-shock protein 70.1 (Hsp70.1). AD brains exhibit gradual but continual ischemic insults that cause perturbed Ca(2+) homeostasis, calpain activation, amyloid β deposition, and oxidative stresses. Membrane lipids such as linoleic and arachidonic acids are vulnerable to the cumulative oxidative stresses, generating a toxic peroxidation product 'hydroxynonenal' that can carbonylate Hsp70.1. Recent data advocate for dual roles of Hsp70.1 as a molecular chaperone for damaged proteins and a guardian of lysosomal integrity. Accordingly, impairments of lysosomal autophagy and stabilization may be driven by the calpain-mediated cleavage of carbonylated Hsp70.1, and this causes lysosomal permeabilization and/or rupture with the resultant release of the cell degradation enzyme, cathepsins (calpain-cathepsin hypothesis). Here, the author discusses three topics; (1) how age-related decrease in lysosomal and autophagic activities has a causal connection to programmed neuronal necrosis in sporadic AD, (2) how genetic factors such as apolipoprotein E and presenilin 1 can facilitate lysosomal destabilization in the sequential molecular events, and (3) whether a single cascade can simultaneously account for implications of all players previously reported. In conclusion, Alzheimer neuronal death conceivably occurs by the similar 'calpain-hydroxynonenal-Hsp70.1-cathepsin cascade' with ischemic neuronal death. Blockade of calpain and/or extra-lysosomal cathepsins as well as scavenging of hydroxynonenal would become effective AD therapeutic approaches.
Collapse
Affiliation(s)
- Tetsumori Yamashima
- Department of Restorative Neurosurgery, Kanazawa University Graduate School of Medical Science, Takara-machi 13-1, Kanazawa 920-8641, Japan.
| |
Collapse
|
46
|
Affiliation(s)
- Dave C. Anderson
- Center for Advanced Drug Research; SRI International; 140 Research Drive; Harrisonburg; Virginia; 22802; USA
| |
Collapse
|
47
|
Griffiths HH, Whitehouse IJ, Hooper NM. Regulation of amyloid-β production by the prion protein. Prion 2012; 6:217-22. [PMID: 22449984 DOI: 10.4161/pri.18988] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Alzheimer disease (AD) is characterized by the amyloidogenic processing of the amyloid precursor protein (APP), culminating in the accumulation of amyloid-β peptides in the brain. The enzymatic action of the β-secretase, BACE1 is the rate-limiting step in this amyloidogenic processing of APP. BACE1 cleavage of wild-type APP (APPWT) is inhibited by the cellular prion protein (PrP (C) ). Our recent study has revealed the molecular and cellular mechanisms behind this observation by showing that PrP (C) directly interacts with the pro-domain of BACE1 in the trans-Golgi network (TGN), decreasing the amount of BACE1 at the cell surface and in endosomes where it cleaves APPWT, while increasing BACE1 in the TGN where it preferentially cleaves APP with the Swedish mutation (APPSwe). PrP (C) deletion in transgenic mice expressing the Swedish and Indiana familial mutations (APPSwe,Ind) failed to affect amyloid-β accumulation, which is explained by the differential subcellular sites of action of BACE1 toward APPWT and APPSwe. This, together with our observation that PrP (C) is reduced in sporadic but not familial AD brain, suggests that PrP (C) plays a key protective role against sporadic AD. It also highlights the need for an APPWT transgenic mouse model to understand the molecular and cellular mechanisms underlying sporadic AD.
Collapse
Affiliation(s)
- Heledd H Griffiths
- Faculty of Biological Sciences, Institute of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | | | | |
Collapse
|
48
|
Moore BD, Chakrabarty P, Levites Y, Kukar TL, Baine AM, Moroni T, Ladd TB, Das P, Dickson DW, Golde TE. Overlapping profiles of Aβ peptides in the Alzheimer's disease and pathological aging brains. ALZHEIMERS RESEARCH & THERAPY 2012; 4:18. [PMID: 22621179 PMCID: PMC3506932 DOI: 10.1186/alzrt121] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 04/17/2012] [Accepted: 05/23/2012] [Indexed: 12/11/2022]
Abstract
INTRODUCTION A hallmark of Alzheimer's disease (AD) is the presence of senile plaques composed of aggregated amyloid β (Aβ) peptides. Pathological aging (PA) is a postmortem classification that has been used to describe brains with plaque pathology similar in extent to AD, minimal cortical tau pathology, and no accompanying history of cognitive decline in the brain donor prior to death. PA may represent either a prodromal phase of AD, a benign form of Aβ accumulation, or inherent individual resistance to the toxic effects of Aβ accumulation. To attempt to distinguish between these possibilities we have systematically characterized Aβ peptides in a postmortem series of PA, AD and non-demented control (NDC) brains. METHODS Aβ was sequentially extracted with tris buffered saline (TBS), radioimmunoprecipitation buffer (RIPA), 2% sodium dodecyl sulfate (SDS) and 70% formic acid (FA) from the pre-frontal cortex of 16 AD, eight PA, and six NDC patients. These extracts were analyzed by 1) a panel of Aβ sandwich ELISAs, 2) immunoprecipitation followed by mass spectrometry (IP/MS) and 3) western blotting. These studies enabled us to asses Aβ levels and solubility, peptide profiles and oligomeric assemblies. RESULTS In almost all extracts (TBS, RIPA, 2% SDS and 70% FA) the average levels of Aβ1-40, Aβ1-42, Aβ total, and Aβx-42 were greatest in AD. On average, levels were slightly lower in PA, and there was extensive overlap between Aβ levels in individual PA and AD cases. The profiles of Aβ peptides detected using IP/MS techniques also showed extensive similarity between the PA and AD brain extracts. In select AD brain extracts, we detected more amino-terminally truncated Aβ peptides compared to PA patients, but these peptides represented a minor portion of the Aβ observed. No consistent differences in the Aβ assemblies were observed by western blotting in the PA and AD groups. CONCLUSIONS We found extensive overlap with only subtle quantitative differences between Aβ levels, peptide profiles, solubility, and SDS-stable oligomeric assemblies in the PA and AD brains. These cross-sectional data indicate that Aβ accumulation in PA and AD is remarkably similar. Such data would be consistent with PA representing a prodromal stage of AD or a resistance to the toxic effects of Aβ.
Collapse
Affiliation(s)
- Brenda D Moore
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, 1275 Center Drive, Gainesville, FL, 32610, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Bibl M, Gallus M, Welge V, Esselmann H, Wolf S, Rüther E, Wiltfang J. Cerebrospinal fluid amyloid-β 2-42 is decreased in Alzheimer's, but not in frontotemporal dementia. J Neural Transm (Vienna) 2012; 119:805-13. [PMID: 22527776 PMCID: PMC3605494 DOI: 10.1007/s00702-012-0801-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Accepted: 03/22/2012] [Indexed: 01/09/2023]
Abstract
Alzheimer’s dementia (AD) and frontotemporal dementias (FTD) are common and their clinical differential diagnosis may be complicated by overlapping symptoms, which is why biomarkers may have an important role to play. Cerebrospinal fluids (CSF) Aβ2-42 and 1-42 have been shown to be similarly decreased in AD, but 1-42 did not display sufficient specificity for exclusion of other dementias from AD. The objective of the present study was to clarify the diagnostic value of Aβ2-42 peptides for the differential diagnosis of AD from FTD. For this purpose, 20 non-demented disease controls (NDC), 22 patients with AD and 17 with FTD were comparatively analysed by a novel sequential aminoterminally and carboxyterminally specific immunoprecipitation protocol with subsequent Aβ-SDS-PAGE/immunoblot, allowing the quantification of peptides 1-38ox, 2-40 and 2-42 along with Aβ 1-37, 1-38, 1-39, 1-40, 1-40ox and 1-42. CSF Aβ1-42 was decreased in AD as compared to NDC, but not to FTD. In a subgroup of the patients analyzed, the decrease of Abeta2-42 in AD was evident as compared to both NDC and FTD. Aβ1-38 was decreased in FTD as compared to NDC and AD. For differentiating AD from FTD, Aβ1-42 demonstrated sufficient diagnostic accuracies only when combined with Aβ1-38. Aβ2-42 yielded diagnostic accuracies of over 85 % as a single marker. These accuracy figures could be improved by combining Aβ2-42 to Aβ1-38. Aβ2-42 seems to be a promising biomarker for differentiating AD from other degenerative dementias, such as FTD.
Collapse
Affiliation(s)
- Mirko Bibl
- Department of Psychiatry, University of Goettingen, von-Siebold-Str. 5, 37075, Goettingen, Germany.
| | | | | | | | | | | | | |
Collapse
|