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Cheng F, Fransson LÅ, Mani K. Interplay between glypican-1, amyloid-β and tau phosphorylation in human neural stem cells. Neuroscience 2024:S0306-4522(24)00310-5. [PMID: 38992568 DOI: 10.1016/j.neuroscience.2024.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 06/19/2024] [Accepted: 07/04/2024] [Indexed: 07/13/2024]
Abstract
INTRODUCTION Alzheimeŕs disease (AD) is characterized by accumulation of amyloid beta (Aβ) and hyperphosphorylated tau (Tau-P) in the brain. Aβ enhances the activity of kinases involved in the formation of Tau-P. Phosphorylation at Thr 181 determines the propagation of multiple tau phosphorylations. Aβ is derived from the amyloid precursor protein (APP). Cleavage of APP by β-secretase also initiates release of heparan sulfate (HS) from the proteoglycan glypican-1 (GPC1). OBJECTIVES In this study, we have explored possible connections between GPC1 expression, HS release, APP processing and Tau-P formation in human neural stem cells. METHODS GPC1 formation was suppressed by using CRISPR/Cas9 and increased by using a vector encoding GPC1. HS release from GPC1 was increased by growing cells in medium containing Arg and ascorbate. Effects were monitored by immunofluorescence microscopy and slot immunoblotting using antibodies/antisera recognizing Aβ, GPC1, HS released from GPC1, total Tau, and Tau phosphorylated at Thr-181, 217 or 231. The latter have been used as blood biomarkers for AD. RESULTS Suppression of GPC1 expression resulted in increased phosphorylation at Thr 181 and Thr 217. When GPC1 was overexpressed, phosphorylation at Thr 217 decreased. Stimulation of HS release from GPC1 diminished tau phosphorylation at all of the three Thr positions, while expression of GPC1 was unaffected. Simultaneous stimulation of HS release and APP processing by the cytokine TNF-α also suppressed tau phosphorylation. CONCLUSION The increased release of GPC1-derived HS may interfere with Aβ formation and/or Aβ interaction with tau.
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Affiliation(s)
- Fang Cheng
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden
| | - Lars-Åke Fransson
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden
| | - Katrin Mani
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden.
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2
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Nguyen DLB, Okolicsanyi RK, Haupt LM. Heparan sulfate proteoglycans: Mediators of cellular and molecular Alzheimer's disease pathogenic factors via tunnelling nanotubes? Mol Cell Neurosci 2024; 129:103936. [PMID: 38750678 DOI: 10.1016/j.mcn.2024.103936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/14/2024] [Accepted: 05/01/2024] [Indexed: 05/19/2024] Open
Abstract
Neurological disorders impact around one billion individuals globally (15 % approx.), with significant implications for disability and mortality with their impact in Australia currently amounts to 6.8 million deaths annually. Heparan sulfate proteoglycans (HSPGs) are complex extracellular molecules implicated in promoting Tau fibril formation resulting in Tau tangles, a hallmark of Alzheimer's disease (AD). HSPG-Tau protein interactions contribute to various AD stages via aggregation, toxicity, and clearance, largely via interactions with the glypican 1 and syndecan 3 core proteins. The tunnelling nanotubes (TNTs) pathway is emerging as a facilitator of intercellular molecule transport, including Tau and Amyloid β proteins, across extensive distances. While current TNT-associated evidence primarily stems from cancer models, their role in Tau propagation and its effects on recipient cells remain unclear. This review explores the interplay of TNTs, HSPGs, and AD-related factors and proposes that HSPGs influence TNT formation in neurodegenerative conditions such as AD.
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Affiliation(s)
- Duy L B Nguyen
- Stem Cell and Neurogenesis Group, Genomics Research Centre, Centre for Genomics and Personalised Health, School of Biomedical Sciences, Queensland University of Technology (QUT), 60 Musk Ave., Kelvin Grove, Queensland 4059, Australia
| | - Rachel K Okolicsanyi
- Stem Cell and Neurogenesis Group, Genomics Research Centre, Centre for Genomics and Personalised Health, School of Biomedical Sciences, Queensland University of Technology (QUT), 60 Musk Ave., Kelvin Grove, Queensland 4059, Australia; ARC Training Centre for Cell and Tissue Engineering Technologies, Queensland University of Technology (QUT), Australia
| | - Larisa M Haupt
- Stem Cell and Neurogenesis Group, Genomics Research Centre, Centre for Genomics and Personalised Health, School of Biomedical Sciences, Queensland University of Technology (QUT), 60 Musk Ave., Kelvin Grove, Queensland 4059, Australia; Centre for Biomedical Technologies, Queensland University of Technology (QUT), 60 Musk Ave., Kelvin Grove, QLD 4059, Australia; ARC Training Centre for Cell and Tissue Engineering Technologies, Queensland University of Technology (QUT), Australia; Max Planck Queensland Centre for the Materials Sciences of Extracellular Matrices, Queensland University of Technology (QUT), Australia.
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Ozsan McMillan I, Li JP, Wang L. Heparan sulfate proteoglycan in Alzheimer's disease: aberrant expression and functions in molecular pathways related to amyloid-β metabolism. Am J Physiol Cell Physiol 2023; 324:C893-C909. [PMID: 36878848 PMCID: PMC10069967 DOI: 10.1152/ajpcell.00247.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 02/28/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Currently, there is no effective treatment for AD, as its etiology remains poorly understood. Mounting evidence suggests that the accumulation and aggregation of amyloid-β peptides (Aβ), which constitute amyloid plaques in the brain, is critical for initiating and accelerating AD pathogenesis. Considerable efforts have been dedicated to shedding light on the molecular basis and fundamental origins of the impaired Aβ metabolism in AD. Heparan sulfate (HS), a linear polysaccharide of the glycosaminoglycan family, co-deposits with Aβ in plaques in the AD brain, directly binds and accelerates Aβ aggregation, and mediates Aβ internalization and cytotoxicity. Mouse model studies demonstrate that HS regulates Aβ clearance and neuroinflammation in vivo. Previous reviews have extensively explored these discoveries. Here, this review focuses on the recent advancements in understanding abnormal HS expression in the AD brain, the structural aspects of HS-Aβ interaction, and the molecules involved in modulating Aβ metabolism through HS interaction. Furthermore, this review presents a perspective on the potential effects of abnormal HS expression on Aβ metabolism and AD pathogenesis. In addition, the review highlights the importance of conducting further research to differentiate the spatiotemporal components of HS structure and function in the brain and AD pathogenesis.
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Affiliation(s)
- Ilayda Ozsan McMillan
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Jin-Ping Li
- Department of Medical Biochemistry and Microbiology & The Biomedical Center, University of Uppsala, Uppsala, Sweden
- SciLifeLab Uppsala, University of Uppsala, Uppsala, Sweden
| | - Lianchun Wang
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
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Tohumeken S, Deme P, Yoo SW, Gupta S, Rais R, Slusher BS, Haughey NJ. Neuronal deletion of nSMase2 reduces the production of Aβ and directly protects neurons. Neurobiol Dis 2023; 177:105987. [PMID: 36603748 DOI: 10.1016/j.nbd.2023.105987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 12/28/2022] [Accepted: 01/01/2023] [Indexed: 01/03/2023] Open
Abstract
Extracellular vesicles (EVs) have been proposed to regulate the deposition of Aβ. Multiple publications have shown that APP, amyloid processing enzymes and Aβ peptides are associated with EVs. However, very little Aβ is associated with EVs compared with the total amount Aβ present in human plasma, CSF, or supernatants from cultured neurons. The involvement of EVs has largely been inferred by pharmacological inhibition or whole body deletion of the sphingomyelin hydrolase neutral sphingomyelinase-2 (nSMase2) that is a key regulator for the biogenesis of at-least one population of EVs. Here we used a Cre-Lox system to selectively delete nSMase2 from pyramidal neurons in APP/PS1 mice (APP/PS1-SMPD3-Nex1) and found a ∼ 70% reduction in Aβ deposition at 6 months of age and ∼ 35% reduction at 12 months of age in both cortex and hippocampus. Brain ceramides were increased in APP/PS1 compared with Wt mice, but were similar to Wt in APP/PS1-SMPD3-Nex1 mice suggesting that elevated brain ceramides in this model involves neuronally expressed nSMase2. Reduced levels of PSD95 and deficits of long-term potentiation in APP/PS1 mice were normalized in APP/PS1-SMPD3-Nex1 mice. In contrast, elevated levels of IL-1β, IL-8 and TNFα in APP/PS1 mice were not normalized in APP/PS1-SMPD3-Nex1 mice compared with APP/PS1 mice. Mechanistic studies showed that the size of liquid ordered membrane microdomains was increased in APP/PS1 mice, as were the amounts of APP and BACE1 localized to these microdomains. Pharmacological inhibition of nSMase2 activity with PDDC reduced the size of the liquid ordered membrane microdomains, reduced the localization of APP with BACE1 and reduced the production of Aβ1-40 and Aβ1-42. Although inhibition of nSMase2 reduced the release and increased the size of EVs, very little Aβ was associated with EVs in all conditions tested. We also found that nSMase2 directly protected neurons from the toxic effects of oligomerized Aβ and preserved neural network connectivity despite considerable Aβ deposition. These data demonstrate that nSMase2 plays a role in the production of Aβ by stabilizing the interaction of APP with BACE1 in liquid ordered membrane microdomains, and directly protects neurons from the toxic effects of Aβ. The effects of inhibiting nSMase2 on EV biogenesis may be independent from effects on Aβ production and neuronal protection.
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Affiliation(s)
- Sehmus Tohumeken
- The Johns Hopkins University School of Medicine, Departments of Neurology, United States of America
| | - Pragney Deme
- The Johns Hopkins University School of Medicine, Departments of Neurology, United States of America
| | - Seung Wan Yoo
- The Johns Hopkins University School of Medicine, Departments of Neurology, United States of America
| | - Sujasha Gupta
- The Johns Hopkins University School of Medicine, Departments of Neurology, United States of America
| | - Rana Rais
- The Johns Hopkins University School of Medicine, Departments of Psychiatry, United States of America
| | - Barbara S Slusher
- The Johns Hopkins University School of Medicine, Departments of Neurology, United States of America; The Johns Hopkins University School of Medicine, Departments of Johns Hopkins Drug Discovery, United States of America; The Johns Hopkins University School of Medicine, Departments of Psychiatry, United States of America; The Johns Hopkins University School of Medicine, Departments of Pharmacology and Molecular Sciences, United States of America; The Johns Hopkins University School of Medicine, Departments of Department of Oncology, United States of America; The Johns Hopkins University School of Medicine, Departments of Department of Neuroscience, United States of America; The Johns Hopkins University School of Medicine, Departments of Department of Medicine, Baltimore, MD, United States of America
| | - Norman J Haughey
- The Johns Hopkins University School of Medicine, Departments of Neurology, United States of America; The Johns Hopkins University School of Medicine, Departments of Johns Hopkins Drug Discovery, United States of America.
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Busato D, Mossenta M, Dal Bo M, Macor P, Toffoli G. The Proteoglycan Glypican-1 as a Possible Candidate for Innovative Targeted Therapeutic Strategies for Pancreatic Ductal Adenocarcinoma. Int J Mol Sci 2022; 23:ijms231810279. [PMID: 36142190 PMCID: PMC9499405 DOI: 10.3390/ijms231810279] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/02/2022] [Accepted: 09/04/2022] [Indexed: 11/19/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) accounts for 90% of all pancreatic cancers, with a 5-year survival rate of 7% and 80% of patients diagnosed with advanced or metastatic malignancies. Despite recent advances in diagnostic testing, surgical techniques, and systemic therapies, there remain limited options for the effective treatment of PDAC. There is an urgent need to develop targeted therapies that are able to differentiate between cancerous and non-cancerous cells to reduce side effects and better inhibit tumor growth. Antibody-targeted strategies are a potentially effective option for introducing innovative therapies. Antibody-based immunotherapies and antibody-conjugated nanoparticle-based targeted therapies with antibodies targeting specific tumor-associated antigens (TAA) can be proposed. In this context, glypican-1 (GPC1), which is highly expressed in PDAC and not expressed or expressed at very low levels in non-malignant lesions and healthy pancreatic tissues, is a useful TAA that can be achieved by a specific antibody-based immunotherapy and antibody-conjugated nanoparticle-based targeted therapy. In this review, we describe the main clinical features of PDAC. We propose the proteoglycan GPC1 as a useful TAA for PDAC-targeted therapies. We also provide a digression on the main developed approaches of antibody-based immunotherapy and antibody-conjugated nanoparticle-based targeted therapy, which can be used to target GPC1.
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Affiliation(s)
- Davide Busato
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081 Aviano, Italy
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
- Correspondence: ; Tel.: +39-0434-659816
| | - Monica Mossenta
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081 Aviano, Italy
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Michele Dal Bo
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081 Aviano, Italy
| | - Paolo Macor
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Giuseppe Toffoli
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081 Aviano, Italy
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A Method for Bridging Population-Specific Genotypes to Detect Gene Modules Associated with Alzheimer's Disease. Cells 2022; 11:cells11142219. [PMID: 35883662 PMCID: PMC9319087 DOI: 10.3390/cells11142219] [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: 05/29/2022] [Revised: 07/12/2022] [Accepted: 07/14/2022] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Genome-wide association studies have successfully identified variants associated with multiple conditions. However, generalizing discoveries across diverse populations remains challenging due to large variations in genetic composition. Methods that perform gene expression imputation have attempted to address the transferability of gene discoveries across populations, but with limited success. METHODS Here, we introduce a pipeline that combines gene expression imputation with gene module discovery, including a dense gene module search and a gene set variation analysis, to address the transferability issue. Our method feeds association probabilities of imputed gene expression with a selected phenotype into tissue-specific gene-module discovery over protein interaction networks to create higher-level gene modules. RESULTS We demonstrate our method's utility in three case-control studies of Alzheimer's disease (AD) for three different race/ethnic populations (Whites, African descent and Hispanics). We discovered 182 AD-associated genes from gene modules shared between these populations, highlighting new gene modules associated with AD. CONCLUSIONS Our innovative framework has the potential to identify robust discoveries across populations based on gene modules, as demonstrated in AD.
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Blood-brain barrier leakage in Alzheimer's disease: From discovery to clinical relevance. Pharmacol Ther 2022; 234:108119. [PMID: 35108575 PMCID: PMC9107516 DOI: 10.1016/j.pharmthera.2022.108119] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 12/16/2022]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. AD brain pathology starts decades before the onset of clinical symptoms. One early pathological hallmark is blood-brain barrier dysfunction characterized by barrier leakage and associated with cognitive decline. In this review, we summarize the existing literature on the extent and clinical relevance of barrier leakage in AD. First, we focus on AD animal models and their susceptibility to barrier leakage based on age and genetic background. Second, we re-examine barrier dysfunction in clinical and postmortem studies, summarize changes that lead to barrier leakage in patients and highlight the clinical relevance of barrier leakage in AD. Third, we summarize signaling mechanisms that link barrier leakage to neurodegeneration and cognitive decline in AD. Finally, we discuss clinical relevance and potential therapeutic strategies and provide future perspectives on investigating barrier leakage in AD. Identifying mechanistic steps underlying barrier leakage has the potential to unravel new targets that can be used to develop novel therapeutic strategies to repair barrier leakage and slow cognitive decline in AD and AD-related dementias.
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8
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Moretto E, Stuart S, Surana S, Vargas JNS, Schiavo G. The Role of Extracellular Matrix Components in the Spreading of Pathological Protein Aggregates. Front Cell Neurosci 2022; 16:844211. [PMID: 35573838 PMCID: PMC9100790 DOI: 10.3389/fncel.2022.844211] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/08/2022] [Indexed: 11/23/2022] Open
Abstract
Several neurodegenerative diseases are characterized by the accumulation of aggregated misfolded proteins. These pathological agents have been suggested to propagate in the brain via mechanisms similar to that observed for the prion protein, where a misfolded variant is transferred from an affected brain region to a healthy one, thereby inducing the misfolding and/or aggregation of correctly folded copies. This process has been characterized for several proteins, such as α-synuclein, tau, amyloid beta (Aβ) and less extensively for huntingtin and TDP-43. α-synuclein, tau, TDP-43 and huntingtin are intracellular proteins, and their aggregates are located in the cytosol or nucleus of neurons. They have been shown to spread between cells and this event occurs, at least partially, via secretion of these protein aggregates in the extracellular space followed by re-uptake. Conversely, Aβ aggregates are found mainly extracellularly, and their spreading occurs in the extracellular space between brain regions. Due to the inherent nature of their spreading modalities, these proteins are exposed to components of the extracellular matrix (ECM), including glycans, proteases and core matrix proteins. These ECM components can interact with or process pathological misfolded proteins, potentially changing their properties and thus regulating their spreading capabilities. Here, we present an overview of the documented roles of ECM components in the spreading of pathological protein aggregates in neurodegenerative diseases with the objective of identifying the current gaps in knowledge and stimulating further research in the field. This could potentially lead to the identification of druggable targets to slow down the spreading and/or progression of these pathologies.
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Affiliation(s)
- Edoardo Moretto
- Institute of Neuroscience, National Research Council, CNR, Milan, Italy
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- *Correspondence: Edoardo Moretto,
| | - Skye Stuart
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Sunaina Surana
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, United Kingdom
| | - Jose Norberto S. Vargas
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, United Kingdom
| | - Giampietro Schiavo
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, United Kingdom
- Giampietro Schiavo,
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Drummond E, Kavanagh T, Pires G, Marta-Ariza M, Kanshin E, Nayak S, Faustin A, Berdah V, Ueberheide B, Wisniewski T. The amyloid plaque proteome in early onset Alzheimer's disease and Down syndrome. Acta Neuropathol Commun 2022; 10:53. [PMID: 35418158 PMCID: PMC9008934 DOI: 10.1186/s40478-022-01356-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/28/2022] [Indexed: 11/17/2022] Open
Abstract
Amyloid plaques contain many proteins in addition to beta amyloid (Aβ). Previous studies examining plaque-associated proteins have shown these additional proteins are important; they provide insight into the factors that drive amyloid plaque development and are potential biomarkers or therapeutic targets for Alzheimer's disease (AD). The aim of this study was to comprehensively identify proteins that are enriched in amyloid plaques using unbiased proteomics in two subtypes of early onset AD: sporadic early onset AD (EOAD) and Down Syndrome (DS) with AD. We focused our study on early onset AD as the drivers of the more aggressive pathology development in these cases is unknown and it is unclear whether amyloid-plaque enriched proteins differ between subtypes of early onset AD. Amyloid plaques and neighbouring non-plaque tissue were microdissected from human brain sections using laser capture microdissection and label-free LC-MS was used to quantify the proteins present. 48 proteins were consistently enriched in amyloid plaques in EOAD and DS. Many of these proteins were more significantly enriched in amyloid plaques than Aβ. The most enriched proteins in amyloid plaques in both EOAD and DS were: COL25A1, SMOC1, MDK, NTN1, OLFML3 and HTRA1. Endosomal/lysosomal proteins were particularly highly enriched in amyloid plaques. Fluorescent immunohistochemistry was used to validate the enrichment of four proteins in amyloid plaques (moesin, ezrin, ARL8B and SMOC1) and to compare the amount of total Aβ, Aβ40, Aβ42, phosphorylated Aβ, pyroglutamate Aβ species and oligomeric species in EOAD and DS. These studies showed that phosphorylated Aβ, pyroglutamate Aβ species and SMOC1 were significantly higher in DS plaques, while oligomers were significantly higher in EOAD. Overall, we observed that amyloid plaques in EOAD and DS largely contained the same proteins, however the amount of enrichment of some proteins was different in EOAD and DS. Our study highlights the significant enrichment of many proteins in amyloid plaques, many of which may be potential therapeutic targets and/or biomarkers for AD.
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Affiliation(s)
- Eleanor Drummond
- Brain and Mind Centre and School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, 94 Mallett Street, Camperdown, NSW, Australia.
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA.
| | - Tomas Kavanagh
- Brain and Mind Centre and School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, 94 Mallett Street, Camperdown, NSW, Australia
| | - Geoffrey Pires
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA
| | - Mitchell Marta-Ariza
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA
| | - Evgeny Kanshin
- Proteomics Laboratory, Division of Advanced Research Technologies, New York University Grossman School of Medicine, New York, NY, USA
| | - Shruti Nayak
- Merck & Co., Inc, Computational & Structural Chemistry, Kenilworth, NJ, USA
| | - Arline Faustin
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA
| | - Valentin Berdah
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA
| | - Beatrix Ueberheide
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA
- Proteomics Laboratory, Division of Advanced Research Technologies, New York University Grossman School of Medicine, New York, NY, USA
- Department of Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY, USA
| | - Thomas Wisniewski
- Centre for Cognitive Neurology, Department of Neurology, New York University Grossman School of Medicine, Science Building, Rm 1017, 435 East 30th Street, New York, NY, 10016, USA.
- Departments of Pathology and Psychiatry, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA.
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Cheng F, Fransson LÅ, Mani K. Complex modulation of cytokine-induced α-synuclein aggregation by glypican-1-derived heparan sulfate in neural cells. Glycobiology 2021; 32:333-342. [PMID: 34939110 PMCID: PMC8970428 DOI: 10.1093/glycob/cwab126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 12/03/2022] Open
Abstract
In Parkinson’s disease (PD), there is accumulation of α-synuclein (SYN) aggregates in neurons, which is promoted by neuroinflammation. The cytokines TNF-α, IL-1β and IL-6 induce accumulation of degradation products of the amyloid precursor protein (APP) combined with heparan sulfate (HS) chains released from glypican-1 (Gpc-1) by NO-dependent cleavage. We have investigated the effects of the cytokines and HS on SYN aggregation and secretion in dividing human neuroblastoma (SH-SY5Y) and inducible neural progenitor cells (NPC) by using immunofluorescence microscopy, vesicle isolation and slot blotting with antibodies recognizing SYN monomers and aggregates, Gpc-1, the released HS, endosomes, and autophagosomes. In SH-SY5Y cells, the capacity to release HS was fully utilized, while NPC displayed dormant capacity. TNF-α induced increased formation of SYN aggregates and clustering of HS in SH-SY5Y cells. When the supply of NO was simultaneously increased, SYN and HS accumulation disappeared. When NO formation was inhibited, SYN and HS aggregation also disappeared, but there was now a 4-fold increase in SYN secretion. In NPC, IL-6 induced increased aggregation of SYN and stimulated HS release from Gpc-1. Both SYN and HS co-localized with autophagosome marker. When HS-deficient Gpc-1 was simultaneously generated, by using a cyanobacterial neurotoxin, accumulation diminished and there was massive secretion of SYN. We suggest that the cytokines increase APP processing, which initiates NO-dependent release of HS from Gpc-1. The APP degradation products also trigger SYN aggregation. As HS can inhibit APP processing, HS- or NO-deficiency may result in autophagosomal dysfunction and both APP degradation products and SYN are secreted.
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Affiliation(s)
- Fang Cheng
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden
| | - Lars-Åke Fransson
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden
| | - Katrin Mani
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden
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Snow AD, Cummings JA, Lake T. The Unifying Hypothesis of Alzheimer's Disease: Heparan Sulfate Proteoglycans/Glycosaminoglycans Are Key as First Hypothesized Over 30 Years Ago. Front Aging Neurosci 2021; 13:710683. [PMID: 34671250 PMCID: PMC8521200 DOI: 10.3389/fnagi.2021.710683] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 08/23/2021] [Indexed: 01/03/2023] Open
Abstract
The updated "Unifying Hypothesis of Alzheimer's disease" (AD) is described that links all the observed neuropathology in AD brain (i.e., plaques, tangles, and cerebrovascular amyloid deposits), as well as inflammation, genetic factors (involving ApoE), "AD-in-a-Dish" studies, beta-amyloid protein (Aβ) as a microbial peptide; and theories that bacteria, gut microflora, gingivitis and viruses all play a role in the cause of AD. The common link is the early accumulation of heparan sulfate proteoglycans (HSPGs) and heparan sulfate glycosaminoglycans (GAGs). HS GAG accumulation and/or decreased HS GAG degradation is postulated to be the key initiating event. HS GAGs and highly sulfated macromolecules induce Aβ 1-40 (but not 1-42) to form spherical congophilic maltese-cross star-like amyloid core deposits identical to those in the AD brain. Heparin/HS also induces tau protein to form paired helical filaments (PHFs). Increased sulfation and/or decreased degradation of HSPGs and HS GAGs that occur due to brain aging leads to the formation of plaques and tangles in AD brain. Knockout of HS genes markedly reduce the accumulation of Aβ fibrils in the brain demonstrating that HS GAGs are key. Bacteria and viruses all use cell surface HS GAGs for entry into cells, including SARS-CoV-2. Bacteria and viruses cause HS GAGs to rapidly increase to cause near-immediate aggregation of Aβ fibrils. "AD-in-a-dish" studies use "Matrigel" as the underlying scaffold that spontaneously causes plaque, and then tangle formation in a dish. Matrigel mostly contains large amounts of perlecan, the same specific HSPG implicated in AD and amyloid disorders. Mucopolysaccharidoses caused by lack of specific HS GAG enzymes lead to massive accumulation of HS in lysosomal compartments in neurons and contribute to cognitive impairment in children. Neurons full of HS demonstrate marked accumulation and fibrillization of Aβ, tau, α-synuclein, and prion protein (PrP) in mucopolysaccharidosis animal models demonstrating that HS GAG accumulation is a precursor to Aβ accumulation in neurons. Brain aging leads to changes in HSPGs, including newly identified splice variants leading to increased HS GAG sulfation in the AD brain. All of these events lead to the new "Unifying Hypothesis of Alzheimer's disease" that further implicates HSPGs /HS GAGs as key (as first hypothesized by Snow and Wight in 1989).
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12
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Rahman MM, Lendel C. Extracellular protein components of amyloid plaques and their roles in Alzheimer's disease pathology. Mol Neurodegener 2021; 16:59. [PMID: 34454574 PMCID: PMC8400902 DOI: 10.1186/s13024-021-00465-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 06/11/2021] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is pathologically defined by the presence of fibrillar amyloid β (Aβ) peptide in extracellular senile plaques and tau filaments in intracellular neurofibrillary tangles. Extensive research has focused on understanding the assembly mechanisms and neurotoxic effects of Aβ during the last decades but still we only have a brief understanding of the disease associated biological processes. This review highlights the many other constituents that, beside Aβ, are accumulated in the plaques, with the focus on extracellular proteins. All living organisms rely on a delicate network of protein functionality. Deposition of significant amounts of certain proteins in insoluble inclusions will unquestionably lead to disturbances in the network, which may contribute to AD and copathology. This paper provide a comprehensive overview of extracellular proteins that have been shown to interact with Aβ and a discussion of their potential roles in AD pathology. Methods that can expand the knowledge about how the proteins are incorporated in plaques are described. Top-down methods to analyze post-mortem tissue and bottom-up approaches with the potential to provide molecular insights on the organization of plaque-like particles are compared. Finally, a network analysis of Aβ-interacting partners with enriched functional and structural key words is presented.
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Affiliation(s)
- M Mahafuzur Rahman
- Department of Chemistry, KTH Royal Institute of Technology, SE-100 44, Stockholm, Sweden.
| | - Christofer Lendel
- Department of Chemistry, KTH Royal Institute of Technology, SE-100 44, Stockholm, Sweden.
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13
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Zhang X, O’Callaghan P, Li H, Tan Y, Zhang G, Barash U, Wang X, Lannfelt L, Vlodavsky I, Lindahl U, Li JP. Heparanase overexpression impedes perivascular clearance of amyloid-β from murine brain: relevance to Alzheimer's disease. Acta Neuropathol Commun 2021; 9:84. [PMID: 33971986 PMCID: PMC8111754 DOI: 10.1186/s40478-021-01182-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 04/14/2021] [Indexed: 12/23/2022] Open
Abstract
Defective amyloid-β (Aβ) clearance from the brain is a major contributing factor to the pathophysiology of Alzheimer's disease (AD). Aβ clearance is mediated by macrophages, enzymatic degradation, perivascular drainage along the vascular basement membrane (VBM) and transcytosis across the blood-brain barrier (BBB). AD pathology is typically associated with cerebral amyloid angiopathy due to perivascular accumulation of Aβ. Heparan sulfate (HS) is an important component of the VBM, thought to fulfill multiple roles in AD pathology. We previously showed that macrophage-mediated clearance of intracortically injected Aβ was impaired in the brains of transgenic mice overexpressing heparanase (Hpa-tg). This study revealed that perivascular drainage was impeded in the Hpa-tg brain, evidenced by perivascular accumulation of the injected Aβ in the thalamus of Hpa-tg mice. Furthermore, endogenous Aβ accumulated at the perivasculature of Hpa-tg thalamus, but not in control thalamus. This perivascular clearance defect was confirmed following intracortical injection of dextran that was largely retained in the perivasculature of Hpa-tg brains, compared to control brains. Hpa-tg brains presented with thicker VBMs and swollen perivascular astrocyte endfeet, as well as elevated expression of the BBB-associated water-pump protein aquaporin 4 (AQP4). Elevated levels of both heparanase and AQP4 were also detected in human AD brain. These findings indicate that elevated heparanase levels alter the organization and composition of the BBB, likely through increased fragmentation of BBB-associated HS, resulting in defective perivascular drainage. This defect contributes to perivascular accumulation of Aβ in the Hpa-tg brain, highlighting a potential role for heparanase in the pathogenesis of AD.
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14
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Chen Z, Yu Q, Yu Q, Johnson J, Shipman R, Zhong X, Huang J, Asthana S, Carlsson C, Okonkwo O, Li L. In-depth Site-specific Analysis of N-glycoproteome in Human Cerebrospinal Fluid and Glycosylation Landscape Changes in Alzheimer's Disease. Mol Cell Proteomics 2021; 20:100081. [PMID: 33862227 PMCID: PMC8724636 DOI: 10.1016/j.mcpro.2021.100081] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 04/02/2021] [Accepted: 04/03/2021] [Indexed: 01/22/2023] Open
Abstract
As the body fluid that directly interchanges with the extracellular fluid of the central nervous system (CNS), cerebrospinal fluid (CSF) serves as a rich source for CNS-related disease biomarker discovery. Extensive proteome profiling has been conducted for CSF, but studies aimed at unraveling site-specific CSF N-glycoproteome are lacking. Initial efforts into site-specific N-glycoproteomics study in CSF yield limited coverage, hindering further experimental design of glycosylation-based disease biomarker discovery in CSF. In the present study, we have developed an N-glycoproteomic approach that combines enhanced N-glycopeptide sequential enrichment by hydrophilic interaction chromatography (HILIC) and boronic acid enrichment with electron transfer and higher-energy collision dissociation (EThcD) for large-scale intact N-glycopeptide analysis. The application of the developed approach to the analyses of human CSF samples enabled identifications of a total of 2893 intact N-glycopeptides from 511 N-glycosites and 285 N-glycoproteins. To our knowledge, this is the largest site-specific N-glycoproteome dataset reported for CSF to date. Such dataset provides molecular basis for a better understanding of the structure-function relationships of glycoproteins and their roles in CNS-related physiological and pathological processes. As accumulating evidence suggests that defects in glycosylation are involved in Alzheimer's disease (AD) pathogenesis, in the present study, a comparative in-depth N-glycoproteomic analysis was conducted for CSF samples from healthy control and AD patients, which yielded a comparable N-glycoproteome coverage but a distinct expression pattern for different categories of glycoforms, such as decreased fucosylation in AD CSF samples. Altered glycosylation patterns were detected for a number of N-glycoproteins including alpha-1-antichymotrypsin, ephrin-A3 and carnosinase CN1 etc., which serve as potentially interesting targets for further glycosylation-based AD study and may eventually lead to molecular elucidation of the role of glycosylation in AD progression.
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Affiliation(s)
- Zhengwei Chen
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - Qinying Yu
- School of Pharmacy, University of Wisconsin, Madison, Wisconsin, USA
| | - Qing Yu
- School of Pharmacy, University of Wisconsin, Madison, Wisconsin, USA
| | - Jillian Johnson
- School of Pharmacy, University of Wisconsin, Madison, Wisconsin, USA
| | - Richard Shipman
- Department of Applied Science, University of Wisconsin-Stout, Menomonie, Wisconsin, USA
| | - Xiaofang Zhong
- School of Pharmacy, University of Wisconsin, Madison, Wisconsin, USA
| | - Junfeng Huang
- School of Pharmacy, University of Wisconsin, Madison, Wisconsin, USA
| | - Sanjay Asthana
- School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Cynthia Carlsson
- School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Ozioma Okonkwo
- School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin, USA; School of Pharmacy, University of Wisconsin, Madison, Wisconsin, USA.
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15
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Li Z, Moniruzzaman M, Dastgheyb RM, Yoo S, Wang M, Hao H, Liu J, Casaccia P, Nogueras‐Ortiz C, Kapogiannis D, Slusher BS, Haughey NJ. Astrocytes deliver CK1 to neurons via extracellular vesicles in response to inflammation promoting the translation and amyloidogenic processing of APP. J Extracell Vesicles 2020; 10:e12035. [PMID: 33408815 PMCID: PMC7775567 DOI: 10.1002/jev2.12035] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 08/20/2020] [Accepted: 09/09/2020] [Indexed: 12/14/2022] Open
Abstract
Chronic inflammation is thought to contribute to the early pathogenesis of Alzheimer's disease (AD). However, the precise mechanism by which inflammatory cytokines promote the formation and deposition of Aβ remains unclear. Available data suggest that applications of inflammatory cytokines onto isolated neurons do not promote the formation of Aβ, suggesting an indirect mechanism of action. Based on evidence astrocyte derived extracellular vesicles (astrocyte derived EVs) regulate neuronal functions, and data that inflammatory cytokines can modify the molecular cargo of astrocyte derived EVs, we sought to determine if IL-1β promotes the formation of Aβ indirectly through actions of astrocyte derived EVs on neurons. The production of Aβ was increased when neurons were exposed to astrocyte derived EVs shed in response to IL-1β (astrocyte derived EV-IL-1β). The mechanism for this effect involved an enrichment of Casein kinase 1 (CK1) in astrocyte derived EV-IL-1β. This astrocyte derived CK1 was delivered to neurons where it formed a complex with neuronal APC and GSK3 to inhibit the β-catenin degradation. Stabilized β-catenin translocated to the nucleus and bound to Hnrnpc gene at promoter regions. An increased cellular concentration of hnRNP C promoted the translation of APP by outcompeting the translational repressor fragile X mental retardation protein (FMRP) bound to APP mRNA. An increased amount of APP protein became co-localized with BACE1 in enlarged membrane microdomains concurrent with increased production of Aβ. These findings identify a mechanism whereby inflammation promotes the formation of Aβ through the actions of astrocyte derived EV-IL-1β on neurons.
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Affiliation(s)
- Zhigang Li
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Mohammed Moniruzzaman
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Raha M. Dastgheyb
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Seung‐Wan Yoo
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Meina Wang
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Hongbo Hao
- Advanced Science Research Center at the Graduate Center, Neuroscience InitiativeCity University of New YorkNew YorkNew YorkUSA
| | - Jia Liu
- Advanced Science Research Center at the Graduate Center, Neuroscience InitiativeCity University of New YorkNew YorkNew YorkUSA
| | - Patrizia Casaccia
- Advanced Science Research Center at the Graduate Center, Neuroscience InitiativeCity University of New YorkNew YorkNew YorkUSA
| | | | | | - Barbara S. Slusher
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
- Johns Hopkins Drug DiscoveryJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Norman J. Haughey
- Department of Neurology, Richard T. Johnson Division of Neuroimmunology and Neurological InfectionsJohns Hopkins University School of MedicineBaltimoreMarylandUSA
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16
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András IE, Sewell BB, Toborek M. HIV-1 and Amyloid Beta Remodel Proteome of Brain Endothelial Extracellular Vesicles. Int J Mol Sci 2020; 21:ijms21082741. [PMID: 32326569 PMCID: PMC7215366 DOI: 10.3390/ijms21082741] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 01/01/2023] Open
Abstract
Amyloid beta (Aβ) depositions are more abundant in HIV-infected brains. The blood-brain barrier, with its backbone created by endothelial cells, is assumed to be a core player in Aβ homeostasis and may contribute to Aβ accumulation in the brain. Exposure to HIV increases shedding of extracellular vesicles (EVs) from human brain endothelial cells and alters EV-Aβ levels. EVs carrying various cargo molecules, including a complex set of proteins, can profoundly affect the biology of surrounding neurovascular unit cells. In the current study, we sought to examine how exposure to HIV, alone or together with Aβ, affects the surface and total proteomic landscape of brain endothelial EVs. By using this unbiased approach, we gained an unprecedented, high-resolution insight into these changes. Our data suggest that HIV and Aβ profoundly remodel the proteome of brain endothelial EVs, altering the pathway networks and functional interactions among proteins. These events may contribute to the EV-mediated amyloid pathology in the HIV-infected brain and may be relevant to HIV-1-associated neurocognitive disorders.
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17
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Lorente-Gea L, García B, Martín C, Ordiales H, García-Suárez O, Piña-Batista KM, Merayo-Lloves J, Quirós LM, Fernández-Vega I. Heparan Sulfate Proteoglycans Undergo Differential Expression Alterations in Alzheimer Disease Brains. J Neuropathol Exp Neurol 2020; 79:474-483. [PMID: 32232475 DOI: 10.1093/jnen/nlaa016] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 12/22/2019] [Accepted: 02/14/2020] [Indexed: 12/15/2022] Open
Abstract
Previous studies have reported that heparan sulfate proteoglycans (HSPGs) promote amyloid-beta peptide and tau fibrillization in Alzheimer disease (AD) and provide resistance against proteolytic breakdown. We compared the expression levels of 17 HSPG core proteins in 18 AD cases and 6 controls. RT-PCR was used to analyze transcription levels. Immunohistochemistry was performed to localize HSPGs in the brain tissue. We detected expression of all HSPG genes investigated. SDC1, GPC3, and CD44v3 showed the lowest levels of expression, while SDC3 and GPC1 showed the highest. Remarkably, SDC4 and SRGN were overexpressed in most of the areas analyzed. Immunohistochemistry revealed the presence of both SDC4 and SRGN mostly associated with tau and amyloid-β pathology throughout the AD brains. In conclusion, in view of the involvement of HSPGs in AD pathology, especially SDC4 and SRGN, there would seem to be a relationship between the regulation of core protein expression and the pathological features suggesting HSPGs are potential inducers of the disease.
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Affiliation(s)
- Laura Lorente-Gea
- From the Department of Pathology, Hospital Universitario de Araba - Txagorritxu, Spain
| | - Beatriz García
- Department of Functional Biology, University of Oviedo, Oviedo, Spain.,Instituto Universitario Fernández-Vega, Oviedo, Spain
| | - Carla Martín
- Department of Functional Biology, University of Oviedo, Oviedo, Spain.,Instituto Universitario Fernández-Vega, Oviedo, Spain
| | - Helena Ordiales
- Department of Functional Biology, University of Oviedo, Oviedo, Spain
| | | | - Kelvin M Piña-Batista
- Department of Neurosurgery, Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | - Luís M Quirós
- Department of Functional Biology, University of Oviedo, Oviedo, Spain.,Instituto Universitario Fernández-Vega, Oviedo, Spain
| | - Iván Fernández-Vega
- From the Department of Pathology, Hospital Universitario de Araba - Txagorritxu, Spain.,Instituto Universitario Fernández-Vega, Oviedo, Spain.,Department of Pathology, Hospital Universitario Central de Asturias, Oviedo (IF-V) Biobank of Principality of Asturias, Health Research Institute of the Principality of Asturias, Oviedo, Spain.,Biobanco Vasco para la Investigación (O+eHun), Brain Bank, Hospital Universitario Araba, Spain
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18
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Rahman MM, Westermark GT, Zetterberg H, Härd T, Sandgren M. Protofibrillar and Fibrillar Amyloid-β Binding Proteins in Cerebrospinal Fluid. J Alzheimers Dis 2019; 66:1053-1064. [PMID: 30372682 DOI: 10.3233/jad-180596] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Aggregation and deposition of misfolded amyloid-β (Aβ) peptide in the brain is central to Alzheimer's disease (AD). Oligomeric, protofibrillar, and fibrillar forms of Aβ are believed to be neurotoxic and cause neurodegeneration in AD, but the toxicity mechanisms are not well understood and may involve Aβ-interacting molecular partners. In a previous study, we identified potential Aβ42 protofibrillar-binding proteins in serum and cerebrospinal fluid (CSF) using an engineered version of Aβ42 (Aβ42CC) that forms protofibrils, but not fibrils. Here we studied binding of proteins to Aβ42 fibrils in AD and non-AD CSF and compared these with protofibrillar Aβ42CC-binding partners. Aβ42 fibrils sequestered 2.4-fold more proteins than Aβ42CC protofibrils. Proteins with selective binding to fibrillar aggregates with low nanomolar affinity were identified. We also found that protofibrillar and fibrillar Aβ-binding proteins represent distinct functional categories. Aβ42CC protofibrils triggered interactions with proteins involved in catalytic activities, like transferases and oxidoreductases, while Aβ42 fibrils were more likely involved in binding to proteoglycans, growth factors and neuron-associated proteins, e.g., neurexin-1, -2, and -3. Interestingly, 10 brain-enriched proteins were identified among the fibril-binding proteins, while protofibril-extracted proteins had more general expression patterns. Both types of Aβ aggregates bound several extracellular proteins. Additionally, we list a set of CSF proteins that might have potential to discriminate between AD and non-AD CSF samples. The results may be of relevance both for biomarker studies and for studies of Aβ-related toxicity mechanisms.
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Affiliation(s)
- M Mahafuzur Rahman
- Department of Molecular Sciences, Swedish University of Agricultural Sciences (SLU), Uppsala BioCenter, Uppsala, Sweden
| | | | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Torleif Härd
- Department of Molecular Sciences, Swedish University of Agricultural Sciences (SLU), Uppsala BioCenter, Uppsala, Sweden
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences (SLU), Uppsala BioCenter, Uppsala, Sweden
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19
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Wang S, Qiu Y, Bai B. The Expression, Regulation, and Biomarker Potential of Glypican-1 in Cancer. Front Oncol 2019; 9:614. [PMID: 31355137 PMCID: PMC6640540 DOI: 10.3389/fonc.2019.00614] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 06/21/2019] [Indexed: 12/31/2022] Open
Abstract
Glypican-1 (GPC-1) and other glypicans are a family of heparan sulfate proteoglycans. These proteins are highly expressed on the cell membrane and in the extracellular matrix, functioning mainly as modulators of growth factor signaling. Some of them are abnormally expressed in cancer, possibly involved in tumorigenesis, and detectable in blood as potential clinical biomarkers. GPC-1 is another glypican member that has been found to be associated with some cancers, and has increasingly interested the cancer field. Here we provide a brief review about GPC-1 in its expression, signaling and potential as a cancer biomarker.
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Affiliation(s)
- Sen Wang
- Department of Clinical Laboratory Medicine, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Yudong Qiu
- Department of Hepatopancreatobiliary Surgery, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Bing Bai
- Department of Clinical Laboratory Medicine, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
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20
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Karamanos NK, Piperigkou Z, Theocharis AD, Watanabe H, Franchi M, Baud S, Brézillon S, Götte M, Passi A, Vigetti D, Ricard-Blum S, Sanderson RD, Neill T, Iozzo RV. Proteoglycan Chemical Diversity Drives Multifunctional Cell Regulation and Therapeutics. Chem Rev 2018; 118:9152-9232. [DOI: 10.1021/acs.chemrev.8b00354] [Citation(s) in RCA: 193] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Nikos K. Karamanos
- Biochemistry, Biochemical Analysis & Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras 26110, Greece
- Foundation for Research and Technology-Hellas (FORTH)/Institute of Chemical Engineering Sciences (ICE-HT), Patras 26110, Greece
| | - Zoi Piperigkou
- Biochemistry, Biochemical Analysis & Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras 26110, Greece
- Foundation for Research and Technology-Hellas (FORTH)/Institute of Chemical Engineering Sciences (ICE-HT), Patras 26110, Greece
| | - Achilleas D. Theocharis
- Biochemistry, Biochemical Analysis & Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras 26110, Greece
| | - Hideto Watanabe
- Institute for Molecular Science of Medicine, Aichi Medical University, Aichi 480-1195, Japan
| | - Marco Franchi
- Department for Life Quality Studies, University of Bologna, Rimini 47100, Italy
| | - Stéphanie Baud
- Université de Reims Champagne-Ardenne, Laboratoire SiRMa, CNRS UMR MEDyC 7369, Faculté de Médecine, 51 rue Cognacq Jay, Reims 51100, France
| | - Stéphane Brézillon
- Université de Reims Champagne-Ardenne, Laboratoire de Biochimie Médicale et Biologie Moléculaire, CNRS UMR MEDyC 7369, Faculté de Médecine, 51 rue Cognacq Jay, Reims 51100, France
| | - Martin Götte
- Department of Gynecology and Obstetrics, Münster University Hospital, Münster 48149, Germany
| | - Alberto Passi
- Department of Medicine and Surgery, University of Insubria, Varese 21100, Italy
| | - Davide Vigetti
- Department of Medicine and Surgery, University of Insubria, Varese 21100, Italy
| | - Sylvie Ricard-Blum
- University Claude Bernard Lyon 1, CNRS, UMR 5246, Institute of Molecular and Supramolecular Chemistry and Biochemistry, Villeurbanne 69622, France
| | - Ralph D. Sanderson
- Department of Pathology, Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Thomas Neill
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 10107, United States
| | - Renato V. Iozzo
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 10107, United States
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21
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Dai Y, Abbasi K, DePietro M, Butler S, Liu CC. Advanced fabrication of biosensor on detection of Glypican-1 using S-Acetylmercaptosuccinic anhydride (SAMSA) modification of antibody. Sci Rep 2018; 8:13541. [PMID: 30202003 PMCID: PMC6131508 DOI: 10.1038/s41598-018-31994-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 08/28/2018] [Indexed: 12/23/2022] Open
Abstract
Glypican-1 (GPC-1) has been recognized as biomarker of pancreatic cancer. Quantification of GPC-1 level is also pivotal to breast cancer and prostate cancer’s patients. We hereby report the first biosensor for GPC-1 detection. Instead of using crosslinking technique and surface immobilization of antibody, we applied a novel method for biosensor fabrication, using S-Acetylmercaptosuccinic anhydride (SAMSA) to modify the Anti-GPC-1 producing a thiol-linked Anti-GPC-1. The thiol-linked Anti-GPC-1 was then directly formed a single-layer antibody layer on the gold biosensor, minimizing the biosensor preparation steps significantly. Time of Flight Secondary Ions Mass Spectroscopy (TOF-SIMS) characterization verified the thiol-linked antibody layer and demonstrated a unique perspective for surface protein characterization. Differential pulse voltammetry (DPV) was applied to quantify GPC-1 antigen in undiluted human serum with a concentration range of 5,000 pg/µL to 100 pg/µL. The performance of this newly designed biosensor was also compared with modified self-assembled monolayer system fabricated biosensor, demonstrating the high-sensitivity and high-reproducibility of the SAMSA modified antibody based biosensor. This simple fabrication method can also expand to detection of other biomolecules. The simplified operation process shows great potential in clinical application development.
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Affiliation(s)
- Yifan Dai
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA.,Electronics Design Center, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA
| | - Kevin Abbasi
- Swagelok Center for Surface Analysis of Materials (SCSAM), Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA
| | - Michael DePietro
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA
| | - Samantha Butler
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA
| | - Chung Chiun Liu
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA. .,Electronics Design Center, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA.
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Salza R, Lethias C, Ricard-Blum S. The Multimerization State of the Amyloid-β42 Amyloid Peptide Governs its Interaction Network with the Extracellular Matrix. J Alzheimers Dis 2018; 56:991-1005. [PMID: 28106549 DOI: 10.3233/jad-160751] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The goals of this work were i) to identify the interactions of amyloid-β (Aβ)42 under monomeric, oligomeric, and fibrillar forms with the extracellular matrix (ECM) and receptors, ii) to determine the influence of Aβ42 supramolecular organization on these interactions, and iii) to identify the molecular functions, biological processes, and pathways targeted by Aβ42 in the ECM. The ECM and cell surface partners of Aβ42 and its supramolecular forms were identified with protein and glycosaminoglycan (GAG) arrays (81 molecules in triplicate) probed by surface plasmon resonance imaging. The number of partners of Aβ42 increased upon its multimerization, ranging from 4 for the peptide up to 53 for the fibrillar aggregates. The peptide interacted only with ECM proteins but their percentage among Aβ42 partners decreased upon multimerization. Aβ42 and its supramolecular forms recognized different molecular features on their partners, and the partners of Aβ42 fibrillar forms were enriched in laminin IV-A, N-terminal, and EGF-like domains. Aβ42 oligomerization triggered interactions with receptors, whereas Aβ42 fibrillogenesis promoted binding to GAGs, proteoglycans, enzymes, and growth factors and the ability to interact with perineuronal nets. Fibril aggregation bind to further membrane proteins including tumor endothelial marker-8, syndecan-4, and discoidin-domain receptor-2. The partners of the Aβ42 supramolecular forms are enriched in proteins contributing to cell growth and/or maintenance, involved in integrin cell surface interactions and expressed in kidney cancer, preadipocytes, and dentin. In conclusion, the supramolecular assembly of Aβ42 governs its ability to interact in vitro with ECM proteins, remodeling and crosslinking ECM enzymes, proteoglycans, and receptors.
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Affiliation(s)
- Romain Salza
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), UMR 5246 CNRS - Université Lyon 1, Villeurbanne cedex, France
| | - Claire Lethias
- Laboratoire de Biologie Tissulaire et d'Ingénierie Thérapeutique (LBTI), UMR 5305 CNRS - Université Lyon 1, Lyon, Cedex 07, France
| | - Sylvie Ricard-Blum
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), UMR 5246 CNRS - Université Lyon 1, Villeurbanne cedex, France
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Shrivastava AN, Aperia A, Melki R, Triller A. Physico-Pathologic Mechanisms Involved in Neurodegeneration: Misfolded Protein-Plasma Membrane Interactions. Neuron 2017; 95:33-50. [DOI: 10.1016/j.neuron.2017.05.026] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 05/12/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022]
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24
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Liu YL, Chen WT, Lin YY, Lu PH, Hsieh SL, Cheng IHJ. Amelioration of amyloid-β-induced deficits by DcR3 in an Alzheimer's disease model. Mol Neurodegener 2017; 12:30. [PMID: 28438208 PMCID: PMC5402663 DOI: 10.1186/s13024-017-0173-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 04/07/2017] [Indexed: 12/03/2022] Open
Abstract
Background Microglia mediate amyloid-beta peptide (Aβ)-induced neuroinflammation, which is one of the key events in the pathogenesis of Alzheimer’s disease (AD). Decoy receptor 3 (DcR3)/TNFRSF6B is a pleiotropic immunomodulator that promotes macrophage differentiation toward the M2 anti-inflammatory phenotype. Based on its role as an immunosupressor, we examined whether DcR3 could alleviate neuroinflammation and AD-like deficits in the central nervous system. Method We crossed human APP transgenic mice (line J20) with human DcR3 transgenic mice to generate wild-type, APP, DcR3, and APP/DcR3 mice for pathological analysis. The Morris water maze, fear conditioning test, open-field, and elevated-plus maze were used to access their cognitive behavioral changes. Furthermore, the pathological and immune profiles were examined by immunostaining, ELISA, Q-PCR, and IP. In vitro assays were designed to examine DcR3-mediated innate cytokine profile alteration and the potential protective mechanism. Results We reported that DcR3 ameliorates hippocampus-dependent memory deficits and reduces amyloid plaque deposition in APP transgenic mouse. The protective mechanism of DcR3 mediates through interacting with heparan sulfate proteoglycans and activating IL-4+YM1+ M2a-like microglia that reduces Aβ-induced proinflammatory cytokines and promotes phagocytosis ability of microglia. Conclusion The neuroprotective effect of DcR3 is mediated via modulating microglia activation into anti-inflammatory M2a phenotype, and upregulating DcR3 expression in the brain may be a potential therapeutic approach for AD. Electronic supplementary material The online version of this article (doi:10.1186/s13024-017-0173-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yi-Ling Liu
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| | - Wei-Ting Chen
- Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Yu-Yi Lin
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| | - Po-Hung Lu
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| | - Shie-Liang Hsieh
- Genomics Research Center, Academia Sinica, Taipei, Taiwan. .,Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan. .,Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan. .,Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
| | - Irene Han-Juo Cheng
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan. .,Brain Research Center, National Yang-Ming University, Taipei, Taiwan. .,Infection and Immunity Research Center, National Yang-Ming University, Taipei, Taiwan.
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25
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Huynh TPV, Davis AA, Ulrich JD, Holtzman DM. Apolipoprotein E and Alzheimer's disease: the influence of apolipoprotein E on amyloid-β and other amyloidogenic proteins. J Lipid Res 2017; 58:824-836. [PMID: 28246336 DOI: 10.1194/jlr.r075481] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 02/25/2017] [Indexed: 12/13/2022] Open
Abstract
Alzheimer's disease (AD) is one of the fastest-growing causes of death and disability in persons 65 years of age or older, affecting more than 5 million Americans alone. Clinical manifestations of AD include progressive decline in memory, executive function, language, and other cognitive domains. Research efforts within the last three decades have identified APOE as the most significant genetic risk factor for late-onset AD, which accounts for >99% of cases. The apoE protein is hypothesized to affect AD pathogenesis through a variety of mechanisms, from its effects on the blood-brain barrier, the innate immune system, and synaptic function to the accumulation of amyloid-β (Aβ). Here, we discuss the role of apoE on the biophysical properties and metabolism of the Aβ peptide, the principal component of amyloid plaques and cerebral amyloid angiopathy (CAA). CAA is characterized by the deposition of amyloid proteins (including Aβ) in the leptomeningeal medium and small arteries, which is found in most AD cases but sometimes occurs as an independent entity. Accumulation of these pathologies in the brain is one of the pathological hallmarks of AD. Beyond Aβ, we will extend the discussion to the potential role of apoE on other amyloidogenic proteins found in AD, and also a number of diverse neurodegenerative diseases.
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Affiliation(s)
- Tien-Phat V Huynh
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University, St. Louis, MO 63110
| | - Albert A Davis
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University, St. Louis, MO 63110
| | - Jason D Ulrich
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University, St. Louis, MO 63110
| | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University, St. Louis, MO 63110
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26
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Cave C, Park S, Rodriguez M, Nakamura M, Hoke A, Pletnikov M, Sockanathan S. GDE2 is essential for neuronal survival in the postnatal mammalian spinal cord. Mol Neurodegener 2017; 12:8. [PMID: 28103900 PMCID: PMC5244531 DOI: 10.1186/s13024-017-0148-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 01/05/2017] [Indexed: 12/13/2022] Open
Abstract
Background Glycerophosphodiester phosphodiesterase 2 (GDE2) is a six-transmembrane protein that cleaves glycosylphosphatidylinositol (GPI) anchors to regulate GPI-anchored protein activity at the cell surface. In the developing spinal cord, GDE2 utilizes its enzymatic function to regulate the production of specific classes of motor neurons and interneurons; however, GDE2’s roles beyond embryonic neurogenesis have yet to be defined. Method Using a panel of histological, immunohistochemical, electrophysiological, behavioral, and biochemistry techniques, we characterized the postnatal Gde2−/− mouse for evidence of degenerative neuropathology. A conditional deletion of Gde2 was used to study the temporal requirements for GDE2 in neuronal survival. Biochemical approaches identified deficits in the processing of GPI-anchored GDE2 substrates in the SOD1G93A mouse model of familial Amyotrophic Lateral Sclerosis that shows robust motor neuron degeneration. Results Here we show that GDE2 expression continues postnatally, and adult mice lacking GDE2 exhibit a slow, progressive neuronal degeneration with pathologies similar to human neurodegenerative disease. Early phenotypes include vacuolization, microgliosis, cytoskeletal accumulation, and lipofuscin deposition followed by astrogliosis and cell death. Remaining motor neurons exhibit peripheral motor unit restructuring causing behavioral motor deficits. Genetic ablation of GDE2 after embryonic neurogenesis is complete still elicits degenerative pathology, signifying that GDE2’s requirement for neuronal survival is distinct from its involvement in neuronal differentiation. Unbiased screens identify impaired processing of Glypican 4 and 6 in Gde2 null animals, and Glypican release is markedly reduced in SOD1G93A mice. Conclusions This study identifies a novel function for GDE2 in neuronal survival and implicates deregulated GPI-anchored protein activity in pathways mediating neurodegeneration. These findings provide new molecular insight for neuropathologies found in multiple disease settings, and raise the possibility of GDE2 hypofunctionality as a component of neurodegenerative disease. Electronic supplementary material The online version of this article (doi:10.1186/s13024-017-0148-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Clinton Cave
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N Wolfe Street, PCTB 1004, Baltimore, MD, 21205, USA
| | - Sungjin Park
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N Wolfe Street, PCTB 1004, Baltimore, MD, 21205, USA.,University of Utah, BPRB 390D South 2030 East, Salt Lake City, UT, 84112, USA
| | - Marianeli Rodriguez
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N Wolfe Street, PCTB 1004, Baltimore, MD, 21205, USA.,Bascom Palmer Eye Institute, 900 NW 17th St, Miami, FL, 33136, USA
| | - Mai Nakamura
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N Wolfe Street, PCTB 1004, Baltimore, MD, 21205, USA
| | - Ahmet Hoke
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Mikhail Pletnikov
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Shanthini Sockanathan
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N Wolfe Street, PCTB 1004, Baltimore, MD, 21205, USA.
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Sethi MK, Zaia J. Extracellular matrix proteomics in schizophrenia and Alzheimer's disease. Anal Bioanal Chem 2017; 409:379-394. [PMID: 27601046 PMCID: PMC5203946 DOI: 10.1007/s00216-016-9900-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/16/2016] [Accepted: 08/23/2016] [Indexed: 12/17/2022]
Abstract
Brain extracellular matrix (ECM) is a highly organized system that consists of collagens, noncollagenous proteins, glycoproteins, hyaluronan, and proteoglycans. Recognized physiological roles of ECM include developmental regulation, tissue homeostasis, cell migration, cell proliferation, cell differentiation, neuronal plasticity, and neurite outgrowth. Aberrant ECM structure is associated with brain neurodegenerative conditions. This review focuses on two neurodegenerative conditions, schizophrenia and Alzheimer's disease, and summarizes recent findings of altered ECM components, including proteoglycans, glycosaminoglycans, proteins, and glycoproteins, and proteins and genes related to other brain components. The scope includes immunohistochemical, genomics, transcriptomics, proteomics, and glycomics studies, and a critical assessment of current state of proteomic studies for neurodegenerative disorders. The intent is to summarize the ECM molecular alterations associated with neurodegenerative pathophysiology. Graphical Abstract Brain extracellular matrix showing HSPGs, CSPGs, HA, collagens, and other glycoproteins.
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Affiliation(s)
- Manveen K Sethi
- Center for Biomedical Mass Spectrometry, Department of Biochemistry, Cell Biology & Genomics, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Joseph Zaia
- Center for Biomedical Mass Spectrometry, Department of Biochemistry, Cell Biology & Genomics, Boston University School of Medicine, Boston, MA, 02118, USA.
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28
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Liu CC, Zhao N, Yamaguchi Y, Cirrito JR, Kanekiyo T, Holtzman DM, Bu G. Neuronal heparan sulfates promote amyloid pathology by modulating brain amyloid-β clearance and aggregation in Alzheimer's disease. Sci Transl Med 2016; 8:332ra44. [PMID: 27030596 DOI: 10.1126/scitranslmed.aad3650] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 03/11/2016] [Indexed: 12/13/2022]
Abstract
Accumulation of amyloid-β (Aβ) peptide in the brain is the first critical step in the pathogenesis of Alzheimer's disease (AD). Studies in humans suggest that Aβ clearance from the brain is frequently impaired in late-onset AD. Aβ accumulation leads to the formation of Aβ aggregates, which injure synapses and contribute to eventual neurodegeneration. Cell surface heparan sulfates (HSs), expressed on all cell types including neurons, have been implicated in several features in the pathogenesis of AD including its colocalization with amyloid plaques and modulatory role in Aβ aggregation. We show that removal of neuronal HS by conditional deletion of the Ext1 gene, which encodes an essential glycosyltransferase for HS biosynthesis, in postnatal neurons of amyloid model APP/PS1 mice led to a reduction in both Aβ oligomerization and the deposition of amyloid plaques. In vivo microdialysis experiments also detected an accelerated rate of Aβ clearance in the brain interstitial fluid, suggesting that neuronal HS either inhibited or represented an inefficient pathway for Aβ clearance. We found that the amounts of various HS proteoglycans (HSPGs) were increased in postmortem human brain tissues from AD patients, suggesting that this pathway may contribute directly to amyloid pathogenesis. Our findings have implications for AD pathogenesis and provide insight into therapeutic interventions targeting Aβ-HSPG interactions.
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Affiliation(s)
- Chia-Chen Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Na Zhao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Yu Yamaguchi
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - John R Cirrito
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Takahisa Kanekiyo
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA. Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian 361100, China.
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29
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Role of Matricellular Proteins in Disorders of the Central Nervous System. Neurochem Res 2016; 42:858-875. [DOI: 10.1007/s11064-016-2088-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/17/2016] [Accepted: 10/21/2016] [Indexed: 12/15/2022]
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30
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Fu Y, Zhao J, Atagi Y, Nielsen HM, Liu CC, Zheng H, Shinohara M, Kanekiyo T, Bu G. Apolipoprotein E lipoprotein particles inhibit amyloid-β uptake through cell surface heparan sulphate proteoglycan. Mol Neurodegener 2016; 11:37. [PMID: 27151330 PMCID: PMC4857252 DOI: 10.1186/s13024-016-0099-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 04/19/2016] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND The accumulation, aggregation and deposition of amyloid-β (Aβ) peptides in the brain are central to the pathogenesis of Alzheimer's disease (AD). Alzheimer's disease risk increases significantly in individuals carrying one or two copies of APOE ε4 allele compared to individuals with an ε3/ε3 genotype. Growing evidence has demonstrated that apolipoprotein E (apoE) strongly influences AD pathogenesis by controlling Aβ aggregation and metabolism. Heparan sulphate proteoglycans (HSPGs) are abundant cell surface molecules that bind to both apoE and Aβ. HSPGs have been associated with Aβ aggregation and deposition. Although several lines of research have shown that apoE influences Aβ clearance in the brain, it is not clear how apoE influences HSPG-mediated cellular uptake of Aβ. RESULTS In this study, we show that apoE lipoprotein particles from conditioned media of immortalized astrocytes isolated from human APOE-targeted replacement (TR) mice significantly suppress cellular Aβ42 and Aβ40 uptake through cell surface HSPG. ApoE3 and apoE4 particles have similar binding affinity to heparin, while apoE4 particles are likely hypolipidated compared to apoE particles. We also found that the apoE particles antagonize Aβ binding to cell surface, and inhibited Aβ uptake in a concentration-dependent manner in Chinese hamster ovary (CHO) cells. While the effect was not apoE isoform-dependent, the suppressive effect of apoE particles on Aβ uptake was not observed in HSPG-deficient CHO cells. We further demonstrated that apoE particles reduced the internalization of Aβ in mouse primary neurons, an effect that is eliminated by the presence of heparin. CONCLUSIONS Taken together, our findings indicate that apoE particles irrespective of isoform inhibit HSPG-dependent cellular Aβ uptake. Modulating the ability of apoE particles to affect Aβ cellular uptake may hold promises for developing new strategies for AD therapy.
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Affiliation(s)
- Yuan Fu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
- Department of Neurology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang, China
| | - Jing Zhao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Yuka Atagi
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | - Chia-Chen Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Honghua Zheng
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | | | | | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA.
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China.
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In Sickness and in Health: Perineuronal Nets and Synaptic Plasticity in Psychiatric Disorders. Neural Plast 2015; 2016:9847696. [PMID: 26839720 PMCID: PMC4709762 DOI: 10.1155/2016/9847696] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/27/2015] [Indexed: 12/25/2022] Open
Abstract
Rapidly emerging evidence implicates perineuronal nets (PNNs) and extracellular matrix (ECM) molecules that compose or interact with PNNs, in the pathophysiology of several psychiatric disorders. Studies on schizophrenia, autism spectrum disorders, mood disorders, Alzheimer's disease, and epilepsy point to the involvement of ECM molecules such as chondroitin sulfate proteoglycans, Reelin, and matrix metalloproteases, as well as their cell surface receptors. In many of these disorders, PNN abnormalities have also been reported. In the context of the “quadripartite” synapse concept, that is, the functional unit composed of the pre- and postsynaptic terminals, glial processes, and ECM, and of the role that PNNs and ECM molecules play in regulating synaptic functions and plasticity, these findings resonate with one of the most well-replicated aspects of the pathology of psychiatric disorders, that is, synaptic abnormalities. Here we review the evidence for PNN/ECM-related pathology in these disorders, with particular emphasis on schizophrenia, and discuss the hypothesis that such pathology may significantly contribute to synaptic dysfunction.
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32
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Awad W, Adamczyk B, Örnros J, Karlsson NG, Mani K, Logan DT. Structural Aspects of N-Glycosylations and the C-terminal Region in Human Glypican-1. J Biol Chem 2015; 290:22991-3008. [PMID: 26203194 PMCID: PMC4645609 DOI: 10.1074/jbc.m115.660878] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/10/2015] [Indexed: 11/06/2022] Open
Abstract
Glypicans are multifunctional cell surface proteoglycans involved in several important cellular signaling pathways. Glypican-1 (Gpc1) is the predominant heparan sulfate proteoglycan in the developing and adult human brain. The two N-linked glycans and the C-terminal domain that attach the core protein to the cell membrane are not resolved in the Gpc1 crystal structure. Therefore, we have studied Gpc1 using crystallography, small angle x-ray scattering, and chromatographic approaches to elucidate the composition, structure, and function of the N-glycans and the C terminus and also the topology of Gpc1 with respect to the membrane. The C terminus is shown to be highly flexible in solution, but it orients the core protein transverse to the membrane, directing a surface evolutionarily conserved in Gpc1 orthologs toward the membrane, where it may interact with signaling molecules and/or membrane receptors on the cell surface, or even the enzymes involved in heparan sulfate substitution in the Golgi apparatus. Furthermore, the N-glycans are shown to extend the protein stability and lifetime by protection against proteolysis and aggregation.
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Affiliation(s)
- Wael Awad
- From the Department of Biochemistry and Structural Biology, Centre for Molecular Protein Science, Lund University, Box 124, SE-221 00 Lund
| | - Barbara Adamczyk
- the Department of Biochemistry and Cell Biology, University of Gothenburg, Box 440, SE-40530 Gothenburg, and
| | - Jessica Örnros
- the Department of Biochemistry and Cell Biology, University of Gothenburg, Box 440, SE-40530 Gothenburg, and
| | - Niclas G Karlsson
- the Department of Biochemistry and Cell Biology, University of Gothenburg, Box 440, SE-40530 Gothenburg, and
| | - Katrin Mani
- the Department of Experimental Medical Science, Lund University, SE-221 84, Lund, Sweden
| | - Derek T Logan
- From the Department of Biochemistry and Structural Biology, Centre for Molecular Protein Science, Lund University, Box 124, SE-221 00 Lund,
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33
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Dogra P, Martin EB, Williams A, Richardson RL, Foster JS, Hackenback N, Kennel SJ, Sparer TE, Wall JS. Novel heparan sulfate-binding peptides for blocking herpesvirus entry. PLoS One 2015; 10:e0126239. [PMID: 25992785 PMCID: PMC4436313 DOI: 10.1371/journal.pone.0126239] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 03/31/2015] [Indexed: 11/18/2022] Open
Abstract
Human cytomegalovirus (HCMV) infection can lead to congenital hearing loss and mental retardation. Upon immune suppression, reactivation of latent HCMV or primary infection increases morbidity in cancer, transplantation, and late stage AIDS patients. Current treatments include nucleoside analogues, which have significant toxicities limiting their usefulness. In this study we screened a panel of synthetic heparin-binding peptides for their ability to prevent CMV infection in vitro. A peptide designated, p5+14 exhibited ~ 90% reduction in murine CMV (MCMV) infection. Because negatively charged, cell-surface heparan sulfate proteoglycans (HSPGs), serve as the attachment receptor during the adsorption phase of the CMV infection cycle, we hypothesized that p5+14 effectively competes for CMV adsorption to the cell surface resulting in the reduction in infection. Positively charged Lys residues were required for peptide binding to cell-surface HSPGs and reducing viral infection. We show that this inhibition was not due to a direct neutralizing effect on the virus itself and that the peptide blocked adsorption of the virus. The peptide also inhibited infection of other herpesviruses: HCMV and herpes simplex virus 1 and 2 in vitro, demonstrating it has broad-spectrum antiviral activity. Therefore, this peptide may offer an adjunct therapy for the treatment of herpes viral infections and other viruses that use HSPGs for entry.
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Affiliation(s)
- Pranay Dogra
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Emily B. Martin
- Department of Medicine, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Angela Williams
- Department of Medicine, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Raphael L. Richardson
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - James S. Foster
- Department of Medicine, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Nicole Hackenback
- Department of Medicine, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Stephen J. Kennel
- Department of Medicine, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
- Department of Radiology, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Tim E. Sparer
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Jonathan S. Wall
- Department of Medicine, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
- Department of Radiology, The University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
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Wall JS, Martin EB, Richey T, Stuckey AC, Macy S, Wooliver C, Williams A, Foster JS, McWilliams-Koeppen P, Uberbacher E, Cheng X, Kennel SJ. Preclinical Validation of the Heparin-Reactive Peptide p5+14 as a Molecular Imaging Agent for Visceral Amyloidosis. Molecules 2015; 20:7657-82. [PMID: 25923515 PMCID: PMC4442108 DOI: 10.3390/molecules20057657] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 04/22/2015] [Indexed: 01/11/2023] Open
Abstract
Amyloid is a complex pathologic matrix comprised principally of paracrystalline protein fibrils and heparan sulfate proteoglycans. Systemic amyloid diseases are rare, thus, routine diagnosis is often challenging. The glycosaminoglycans ubiquitously present in amyloid deposits are biochemically and electrochemically distinct from those found in the healthy tissues due to the high degree of sulfation. We have exploited this unique property and evaluated heparin-reactive peptides, such as p5+14, as novel agents for specifically targeting and imaging amyloid. Herein, we demonstrate that radiolabeled p5+14 effectively bound murine AA amyloid in vivo by using molecular imaging. Biotinylated peptide also reacted with the major forms of human amyloid in tissue sections as evidenced immunohistochemically. Furthermore, we have demonstrated that the peptide also binds synthetic amyloid fibrils that lack glycosaminoglycans implying that the dense anionic motif present on heparin is mimicked by the amyloid protein fibril itself. These biochemical and functional data support the translation of radiolabeled peptide p5+14 for the clinical imaging of amyloid in patients.
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Affiliation(s)
- Jonathan S Wall
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
- Department of and Radiology, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Emily B Martin
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Tina Richey
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Alan C Stuckey
- Department of and Radiology, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Sallie Macy
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Craig Wooliver
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Angela Williams
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - James S Foster
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Penney McWilliams-Koeppen
- Department of and Radiology, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
| | - Ed Uberbacher
- Bioscience Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Xiaolin Cheng
- Bioscience Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Stephen J Kennel
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
- Department of and Radiology, University of Tennessee Graduate School of Medicine, Knoxville, TN 37920, USA.
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Cheng F, Cappai R, Lidfeldt J, Belting M, Fransson LÅ, Mani K. Amyloid precursor protein (APP)/APP-like protein 2 (APLP2) expression is required to initiate endosome-nucleus-autophagosome trafficking of glypican-1-derived heparan sulfate. J Biol Chem 2015; 289:20871-8. [PMID: 24898256 DOI: 10.1074/jbc.m114.552810] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Anhydromannose (anMan)-containing heparan sulfate (HS) derived from the proteoglycan glypican-1 is generated in endosomes by an endogenously or ascorbate-induced S-nitrosothiolcatalyzed reaction. Processing of the amyloid precursor protein (APP) and APP-like protein 2 (APLP2) by β- and γ-secretases into amyloid β(A) and Aβ-like peptides also takes place in these compartments. Moreover, anMan-containing HS suppresses the formation of toxic Aβ assemblies in vitro. We showed by using deconvolution immunofluorescence microscopy with an anMan-specific monoclonal antibody as well as (35)S labeling experiments that expression of APP/APLP2 is required for ascorbate-induced transport of HS from endosomes to the nucleus. Nuclear translocation was observed in wild-type mouse embryonic fibroblasts (WT MEFs), Tg2576 MEFs, and N2a neuroblastoma cells but not in APP(-/-) and APLP2(-/-) MEFs. Transfection of APP(-/-) cells with a vector encoding APP restored nuclear import of anMan-containing HS. In WT MEFs and N2a neuroblastoma cells exposed to β- or γ-secretase inhibitors, nuclear translocation was greatly impeded, suggesting involvement of APP/APLP2 degradation products. In Tg2576 MEFs, the β-inhibitor blocked transport, but the γ-inhibitor did not. During chase in ascorbate- free medium, anMan-containing HS disappeared from the nuclei of WT MEFs. Confocal immunofluorescence microscopy showed that they appeared in acidic, LC3-positive vesicles in keeping with an autophagosomal location. There was increased accumulation of anMan-containing HS in nuclei and cytosolic vesicles upon treatment with chloroquine, indicating that HS was degraded in lysosomes. Manipulations of APP expression and processing may have deleterious effects upon HS function in the nucleus.
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Leonova EI, Galzitskaya OV. Role of Syndecans in Lipid Metabolism and Human Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 855:241-58. [PMID: 26149933 DOI: 10.1007/978-3-319-17344-3_10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Syndecans are transmembrane heparan sulfate proteoglycans involved in the regulation of cell growth, differentiation, adhesion, neuronal development, and lipid metabolism. Syndecans are expressed in a tissue-specific manner to facilitate diverse cellular processes. As receptors and co-receptors, syndecans provide promising therapeutic targets that bind to a variety of physiologically important ligands. Negatively charged glycosaminoglycan chains of syndecans, located in the extracellular compartment, are critical for such binding. Functions of syndecans are as diverse as their ligands. For example, hepatic syndecan-1 mediates clearance of triglyceride-rich lipoproteins. Syndecan-2 promotes localization of Alzheimer's amyloid Aβ peptide to the cell surface, which is proposed to contribute to amyloid plaque formation. Syndecan-3 helps co-localize the appetite-regulating melanocortin-4 receptor with its agonist, leading to an increased appetite. Finally, syndecan-4 initiates the capture of modified low-density lipoproteins by macrophages and thereby promotes the atheroma formation. We hypothesize that syndecan modifications such as desulfation of glycosaminoglycan chains may contribute to a wide range of diseases, from atherosclerosis to type 2 diabetes. At the same time, desulfated syndecans may have beneficial effects, as they can inhibit amyloid plaque formation or decrease the appetite. Despite considerable progress in understanding diverse functions of syndecans, the complex physiological roles of this intriguing family of proteoglycans are far from clear. Additional studies of syndecans may potentially help develop novel therapeutic approaches and diagnostic tools to alleviate complex human diseases such as cardiovascular and Alzheimer's diseases.
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Affiliation(s)
- Elena I Leonova
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia,
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Abstract
Antiretroviral therapy extends the lifespan of human immunodeficiency virus (HIV)-infected patients, but many survivors develop premature impairments in cognition. These residual cognitive impairments may involve aberrant deposition of amyloid β-peptides (Aβ). By unknown mechanisms, Aβ accumulates in the lysosomal and autophagic compartments of neurons in the HIV-infected brain. Here we identify the molecular events evoked by the HIV coat protein gp120 that facilitate the intraneuronal accumulation of Aβ. We created a triple transgenic gp120/APP/PS1 mouse that recapitulates intraneuronal deposition of Aβ in a manner reminiscent of the HIV-infected brain. In cultured neurons, we found that the HIV coat protein gp120 increased the transcriptional expression of BACE1 through repression of PPARγ, and increased APP expression by promoting interaction of the translation-activating RBP heterogeneous nuclear ribonucleoprotein C with APP mRNA. APP and BACE1 were colocalized into stabilized membrane microdomains, where the β-cleavage of APP and Aβ formation were enhanced. Aβ-peptides became localized to lysosomes that were engorged with sphingomyelin and calcium. Stimulating calcium efflux from lysosomes with a TRPM1 agonist promoted calcium efflux, luminal acidification, and cleared both sphingomyelin and Aβ from lysosomes. These findings suggest that therapeutics targeted to reduce lysosomal pH in neurodegenerative conditions may protect neurons by facilitating the clearance of accumulated sphingolipids and Aβ-peptides.
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Cheng F, Fransson LÅ, Mani K. Rapid nuclear transit and impaired degradation of amyloid β and glypican-1-derived heparan sulfate in Tg2576 mouse fibroblasts. Glycobiology 2014; 25:548-56. [DOI: 10.1093/glycob/cwu185] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Cheng F, Ruscher K, Fransson LÅ, Mani K. Non-toxic amyloid beta formed in the presence of glypican-1 or its deaminatively generated heparan sulfate degradation products. Glycobiology 2013; 23:1510-9. [PMID: 24026238 DOI: 10.1093/glycob/cwt079] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The amyloid beta (Aβ) peptides (mainly Aβ40 and Aβ42), which are derived from the amyloid precursor protein (APP), can oligomerize into antibody A11-positive, neurotoxic species, believed to be involved in Alzheimer's disease. Interestingly, APP binds strongly to the heparan sulfate (HS) proteoglycan (PG) glypican-1 (Gpc-1) in vitro and both proteins are colocalized inside cells. In endosomes, APP is proteolytically processed to yield Aβ peptides. The HS chains of S-nitrosylated (SNO) Gpc-1 PG are cleaved into anhydromannose (anMan)-containing di- and oligosaccharides by an NO-dependent reaction in the same compartments. Here, we have studied the toxicity of oligomers/aggregates of Aβ40 and Aβ42, as well as Aβ40/42 mixtures that were formed in the presence of immobilized Gpc-1 PG or immobilized HS oligosaccharides. Afterwards, Aβ was displaced from the matrices, analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and assayed for A11 immunoreactivity, for effects on growth of mouse N2a neuroblastoma cells and for membrane leakage in rat cortical neurons. HS generally promoted and accelerated Aβ multimerization into oligomers as well as larger aggregates that were mostly A11 positive and showed toxic effects. However, non-toxic Aβ was formed in the presence of Gpc-1 PG or when anMan-containing HS degradation products were simultaneously generated. Both toxic and non-toxic Aβ peptides were taken up by the cells but toxic forms appeared to enter the nuclei to a larger extent. The protection afforded by the presence of HS degradation products may reflect a normal intracellular function for the Aβ peptides.
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Affiliation(s)
- Fang Cheng
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group
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40
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Cheng F, Cappai R, Ciccotosto GD, Svensson G, Multhaup G, Fransson LÅ, Mani K. Suppression of amyloid beta A11 antibody immunoreactivity by vitamin C: possible role of heparan sulfate oligosaccharides derived from glypican-1 by ascorbate-induced, nitric oxide (NO)-catalyzed degradation. J Biol Chem 2011; 286:27559-72. [PMID: 21642435 DOI: 10.1074/jbc.m111.243345] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Amyloid β (Aβ) is generated from the copper- and heparan sulfate (HS)-binding amyloid precursor protein (APP) by proteolytic processing. APP supports S-nitrosylation of the HS proteoglycan glypican-1 (Gpc-1). In the presence of ascorbate, there is NO-catalyzed release of anhydromannose (anMan)-containing oligosaccharides from Gpc-1-nitrosothiol. We investigated whether these oligosaccharides interact with Aβ during APP processing and plaque formation. anMan immunoreactivity was detected in amyloid plaques of Alzheimer (AD) and APP transgenic (Tg2576) mouse brains by immunofluorescence microscopy. APP/APP degradation products detected by antibodies to the C terminus of APP, but not Aβ oligomers detected by the anti-Aβ A11 antibody, colocalized with anMan immunoreactivity in Tg2576 fibroblasts. A 50-55-kDa anionic, sodium dodecyl sulfate-stable, anMan- and Aβ-immunoreactive species was obtained from Tg2576 fibroblasts using immunoprecipitation with anti-APP (C terminus). anMan-containing HS oligo- and disaccharide preparations modulated or suppressed A11 immunoreactivity and oligomerization of Aβ42 peptide in an in vitro assay. A11 immunoreactivity increased in Tg2576 fibroblasts when Gpc-1 autoprocessing was inhibited by 3-β[2(diethylamino)ethoxy]androst-5-en-17-one (U18666A) and decreased when Gpc-1 autoprocessing was stimulated by ascorbate. Neither overexpression of Gpc-1 in Tg2576 fibroblasts nor addition of copper ion and NO donor to hippocampal slices from 3xTg-AD mice affected A11 immunoreactivity levels. However, A11 immunoreactivity was greatly suppressed by the subsequent addition of ascorbate. We speculate that temporary interaction between the Aβ domain and small, anMan-containing oligosaccharides may preclude formation of toxic Aβ oligomers. A portion of the oligosaccharides are co-secreted with the Aβ peptides and deposited in plaques. These results support the notion that an inadequate supply of vitamin C could contribute to late onset AD in humans.
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Affiliation(s)
- Fang Cheng
- Department of Experimental Medical Science, Division of Neuroscience, Glycobiology Group, Lund University, Biomedical Center A13, SE-221 84 Lund, Sweden
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Haughey NJ, Bandaru VVR, Bae M, Mattson MP. Roles for dysfunctional sphingolipid metabolism in Alzheimer's disease neuropathogenesis. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1801:878-86. [PMID: 20452460 DOI: 10.1016/j.bbalip.2010.05.003] [Citation(s) in RCA: 202] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Revised: 04/29/2010] [Accepted: 05/03/2010] [Indexed: 12/12/2022]
Abstract
Sphingolipids in the membranes of neurons play important roles in signal transduction, either by modulating the localization and activation of membrane-associated receptors or by acting as precursors of bioactive lipid mediators. Activation of cytokine and neurotrophic factor receptors coupled to sphingomyelinases results in the generation of ceramides and gangliosides, which in turn, modify the structural and functional plasticity of neurons. In aging and neurodegenerative conditions such as Alzheimer's disease (AD), there are increased membrane-associated oxidative stress and excessive production and accumulation of ceramides. Studies of brain tissue samples from human subjects, and of experimental models of the diseases, suggest that perturbed sphingomyelin metabolism is a pivotal event in the dysfunction and degeneration of neurons that occurs in AD and HIV dementia. Dietary and pharmacological interventions that target sphingolipid metabolism should be pursued for the prevention and treatment of neurodegenerative disorders.
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Affiliation(s)
- Norman J Haughey
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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Ariga T, Miyatake T, Yu RK. Role of proteoglycans and glycosaminoglycans in the pathogenesis of Alzheimer's disease and related disorders: Amyloidogenesis and therapeutic strategies-A review. J Neurosci Res 2010; 88:2303-15. [DOI: 10.1002/jnr.22393] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Ajmo JM, Bailey LA, Howell MD, Cortez LK, Pennypacker KR, Mehta HN, Morgan D, Gordon MN, Gottschall PE. Abnormal post-translational and extracellular processing of brevican in plaque-bearing mice over-expressing APPsw. J Neurochem 2010; 113:784-95. [PMID: 20180882 DOI: 10.1111/j.1471-4159.2010.06647.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Aggregation of amyloid-beta (Abeta) in the forebrain of Alzheimer's disease (AD) subjects may disturb the molecular organization of the extracellular microenvironment that modulates neural and synaptic plasticity. Proteoglycans are major components of this extracellular environment. To test the hypothesis that Abeta, or another amyloid precursor protein (APP) dependent mechanism modifies the accumulation and/or turnover of extracellular proteoglycans, we examined whether the expression and processing of brevican, an abundant extracellular, chondroitin sulfate (CS)-bearing proteoglycan, were altered in brains of Abeta-depositing transgenic mice (APPsw - APP gene bearing the Swedish mutation) as a model of AD. The molecular size of CS chains attached to brevican was smaller in hippocampal tissue from APPsw mice bearing Abeta deposits compared to non-transgenic mice, likely because of changes in the CS chains. Also, the abundance of the major proteolytic fragment of brevican was markedly diminished in extracts from several telencephalic regions of APPsw mice compared to non-transgenic mice, yet these immunoreactive fragments appeared to accumulate adjacent to the plaque edge. These results suggest that Abeta or APP exert inhibitory effects on proteolytic cleavage mechanisms responsible for synthesis and turnover of proteoglycans. As proteoglycans stabilize synaptic structure and inhibit molecular plasticity, defective brevican processing observed in Abeta-bearing mice and potentially end-stage human AD, may contribute to deficient neural plasticity.
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Affiliation(s)
- Joanne M Ajmo
- Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa, Florida, USA
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44
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Heparan sulfate proteoglycans in amyloidosis. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 93:309-34. [PMID: 20807650 DOI: 10.1016/s1877-1173(10)93013-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Amyloidosis is a generic term for a group of diseases characterized by deposits in different organ systems of insoluble materials composed mainly of distinct fibrillar proteins named amyloid. Besides amyloid, heparan sulfate proteoglycan (HSPG), is commonly found in most amyloid deposits, suggesting that HS/HSPG may be functionally involved in the pathogenesis of amyloidosis. HS or HSPG is found to interact with a number of amyloid proteins, displaying a promoting effect on amyloid fibrilization in vitro. In addition, HS is reported to be involved in processing amyloid precursor proteins and mediate amyloid toxicity. Although little is known about the in vivo mechanisms regarding the codeposition of HS with amyloid proteins in different amyloid diseases, experiments carried out in animal models, especially in transgenic mouse model where HS molecular structure is modified, support an active role for HS in amyloidogenesis. Further experimental evidence is required to strengthen these in vivo findings at a molecular level. Animal models that express mutant forms of HS due to knockout of the enzymes involved in glycosaminoglycan (GAG) biosynthesis are expected to provide valuable tools for studying the implications of HS, as well as other GAGs, in amyloid disorders.
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45
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Kirn-Safran C, Farach-Carson MC, Carson DD. Multifunctionality of extracellular and cell surface heparan sulfate proteoglycans. Cell Mol Life Sci 2009; 66:3421-34. [PMID: 19629389 PMCID: PMC11115568 DOI: 10.1007/s00018-009-0096-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 07/01/2009] [Accepted: 07/06/2009] [Indexed: 02/06/2023]
Abstract
Heparan sulfate proteoglycans are a remarkably diverse family of glycosaminoglycan-bearing protein cores that include the syndecans, the glypicans, perlecan, agrin, and collagen XVIII. Members of this protein class play key roles during normal processes that occur during development, tissue morphogenesis, and wound healing. As key components of basement membranes in organs and tissues, they also participate in selective filtration of biological fluids, in establishing cellular barriers, and in modulation of angiogenesis. The ability to perform these functions is provided both by the features of the protein cores as well as by the unique properties of heparan sulfate, which is assembled as a polymer of N-acetylglucosamine and glucuronic acid and modified by specific enzymes to generate specialized biologically active structures. This article discusses the structures and functions of this amazing family of proteoglycans and provides a platform for further study of the individual members.
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Affiliation(s)
| | - Mary C. Farach-Carson
- Department of Biological Sciences, University of Delaware, Newark, DE 19707 USA
- Present Address: Department of Biochemistry and Cell Biology, Weiss School of Natural Sciences, Rice University, MS-102, P.O. Box 1892, Houston, TX 77251-1892 USA
| | - Daniel D. Carson
- Present Address: Department of Biochemistry and Cell Biology, Weiss School of Natural Sciences, Rice University, MS-102, P.O. Box 1892, Houston, TX 77251-1892 USA
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Kirn-Safran C, Farach-Carson MC, Carson DD. Multifunctionality of extracellular and cell surface heparan sulfate proteoglycans. Cell Mol Life Sci 2009. [DOI: 10.1007/s00018-009-0096-1 doi:dx.doi.org] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
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47
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Tang R, Rosen SD. Functional consequences of the subdomain organization of the sulfs. J Biol Chem 2009; 284:21505-14. [PMID: 19520866 DOI: 10.1074/jbc.m109.028472] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Sulf-1 and Sulf-2 are novel extracellular sulfatases that act on internal glucosamine 6-O-sulfate modifications within heparan sulfate proteoglycans and regulate their interactions with various signaling molecules, including Wnt ligands. Although the Sulfs are multidomain proteins, there is limited information available about how the subdomains contribute to their enzymatic and signaling activities. In this study, we found that both human Sulfs were synthesized as prepro-enzymes and cleaved by a furin-type proteinase to form disulfide-bond linked heterodimers of 75- and 50-kDa subunits. The mature Sulfs were secreted into conditioned medium, as well as retained on the cell membrane. Although the catalytic center resides in the N-terminal 75-kDa subunit, the C-terminal 50-kDa subunit was indispensable for both arylsufatase and glucosamine 6-O-sulfate-endosulfatase activity. We found that the hydrophilic regions of the Sulfs were essential for endosulfatase activity but not for arylsulfatase activity. Using Edman sequencing, we identified furin-type proteinase cleavage sites in Sulf-1 and Sulf-2. Deletion of these sequences resulted in uncleavable forms of Sulfs. The uncleavable Sulfs retained enzymatic activity. However, they were unable to potentiate Wnt signaling, which may be due to their defective localization into lipid rafts on the plasma membrane.
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Affiliation(s)
- Renhong Tang
- Department of Anatomy, University of California, San Francisco, California 94143, USA
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48
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Timmer NM, van Horssen J, Otte-Holler I, Wilhelmus MMM, David G, van Beers J, de Waal RMW, Verbeek MM. Amyloid beta induces cellular relocalization and production of agrin and glypican-1. Brain Res 2009; 1260:38-46. [PMID: 19166823 DOI: 10.1016/j.brainres.2008.12.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 12/12/2008] [Accepted: 12/12/2008] [Indexed: 01/19/2023]
Abstract
The major component of senile plaques and vascular amyloid in Alzheimer's disease (AD) brains is the amyloid beta protein (Abeta). Besides Abeta, several other proteins have been identified in these lesions, in particular heparan sulfate proteoglycans (HSPG). However, it is still unclear, what causes the excessive accumulation of HSPG in AD brains. Therefore, we investigated if Abeta may influence production and expression of two major Abeta-associated HSPG species, agrin and glypican-1. When human brain pericytes (HBP) were cultured in the presence of Abeta, protein and mRNA expression of both agrin and glypican-1 were increased and more radioactive sulfate was incorporated in the glycosaminoglycan fraction of Abeta-treated HBP. Furthermore, after Abeta treatment, these HSPG were found in association with the amyloid fibrils attached to the cell membrane, in contrast to the intracellular agrin and glypican-1 staining observed in untreated cells. We conclude that Abeta can modulate the cellular expression of agrin and glypican-1, which may contribute to the accumulation of these HSPG in AD lesions.
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Affiliation(s)
- Nienke M Timmer
- Department of Neurology, Laboratory of Pediatrics and Neurology, Donders Centre for Brain, Cognition and Behaviour, Alzheimer Centre Nijmegen, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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49
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Löfgren K, Cheng F, Fransson LÅ, Bedecs K, Mani K. Involvement of glypican-1 autoprocessing in scrapie infection. Eur J Neurosci 2008; 28:964-72. [DOI: 10.1111/j.1460-9568.2008.06386.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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50
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Ariga T, McDonald MP, Yu RK. Role of ganglioside metabolism in the pathogenesis of Alzheimer's disease--a review. J Lipid Res 2008; 49:1157-75. [PMID: 18334715 DOI: 10.1194/jlr.r800007-jlr200] [Citation(s) in RCA: 247] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Gangliosides are expressed in the outer leaflet of the plasma membrane of the cells of all vertebrates and are particularly abundant in the nervous system. Ganglioside metabolism is closely associated with the pathology of Alzheimer's disease (AD). AD, the most common form of dementia, is a progressive degenerative disease of the brain characterized clinically by progressive loss of memory and cognitive function and eventually death. Neuropathologically, AD is characterized by amyloid deposits or "senile plaques," which consist mainly of aggregated variants of amyloid beta-protein (Abeta). Abeta undergoes a conformational transition from random coil to ordered structure rich in beta-sheets, especially after addition of lipid vesicles containing GM1 ganglioside. In AD brain, a complex of GM1 and Abeta, termed "GAbeta," has been found to accumulate. In recent years, Abeta and GM1 have been identified in microdomains or lipid rafts. The functional roles of these microdomains in cellular processes are now beginning to unfold. Several articles also have documented the involvement of these microdomains in the pathogenesis of certain neurodegenerative diseases, such as AD. A pivotal neuroprotective role of gangliosides has been reported in in vivo and in vitro models of neuronal injury, Parkinsonism, and related diseases. Here we describe the possible involvement of gangliosides in the development of AD and the therapeutic potentials of gangliosides in this disorder.
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Affiliation(s)
- Toshio Ariga
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912, USA
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