1
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Liu X, Novak B, Namendorf C, Steigenberger B, Zhang Y, Turck CW. Long-lived proteins and DNA as candidate predictive biomarkers for tissue associated diseases. iScience 2024; 27:109642. [PMID: 38632996 PMCID: PMC11022098 DOI: 10.1016/j.isci.2024.109642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/11/2024] [Accepted: 03/26/2024] [Indexed: 04/19/2024] Open
Abstract
Protein turnover is an important mechanism to maintain proteostasis. Long-lived proteins (LLPs) are vulnerable to lose their function due to time-accumulated damages. In this study we employed in vivo stable isotope labeling in mice from birth to postnatal day 89. Quantitative proteomics analysis of ten tissues and plasma identified 2113 LLPs, including widespread and tissue-specific ones. Interestingly, a significant percentage of LLPs was detected in plasma, implying a potential link to age-related cardiovascular diseases. LLPs identified in brains were related to neurodegenerative diseases. In addition, the relative quantification of DNA-derived deoxynucleosides from the same tissues provided information about cellular DNA renewal and showed good correlation with LLPs in the brain. The combined data reveal tissue-specific maps of mouse LLPs that may be involved in pathology due to a low renewal rate and an increased risk of damage. Tissue-derived peripheral LLPs hold promise as biomarkers for aging and age-related diseases.
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Affiliation(s)
- Xiaosong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Haike Road, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bozidar Novak
- Max Planck Institute of Psychiatry, Proteomics and Biomarkers, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Christian Namendorf
- Max Planck Institute of Psychiatry, Clinical Laboratory, Core Unit Analytics and Mass Spectrometry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Barbara Steigenberger
- Mass Spectrometry Core Facility, Max Planck Institute of Biochemistry, D-82152 Martinsried/Munich, Germany
| | - Yaoyang Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Haike Road, Shanghai 201210, China
| | - Christoph W. Turck
- Max Planck Institute of Psychiatry, Proteomics and Biomarkers, Kraepelinstr. 2-10, 80804 Munich, Germany
- Key Laboratory of Animal Models and Human Disease Mechanisms of Yunnan Province, and KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- National Resource Center for Non-human Primates, and National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650107, China
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2
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Kong F, Wu T, Dai J, Cai J, Zhai Z, Zhu Z, Xu Y, Sun T. Knowledge domains and emerging trends of Genome-wide association studies in Alzheimer's disease: A bibliometric analysis and visualization study from 2002 to 2022. PLoS One 2024; 19:e0295008. [PMID: 38241287 PMCID: PMC10798548 DOI: 10.1371/journal.pone.0295008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 11/13/2023] [Indexed: 01/21/2024] Open
Abstract
OBJECTIVES Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive decline in cognitive and behavioral function. Studies have shown that genetic factors are one of the main causes of AD risk. genome-wide association study (GWAS), as a novel and effective tool for studying the genetic risk of diseases, has attracted attention from researchers in recent years and a large number of studies have been conducted. This study aims to summarize the literature on GWAS in AD by bibliometric methods, analyze the current status, research hotspots and future trends in this field. METHODS We retrieved articles on GWAS in AD published between 2002 and 2022 from Web of Science. CiteSpace and VOSviewer software were applied to analyze the articles for the number of articles published, countries/regions and institutions of publication, authors and cited authors, highly cited literature, and research hotspots. RESULTS We retrieved a total of 2,751 articles. The United States had the highest number of publications in this field, and Columbia University was the institution with the most published articles. The identification of AD-related susceptibility genes and their effects on AD is one of the current research hotspots. Numerous risk genes have been identified, among which APOE, CLU, CD2AP, CD33, EPHA1, PICALM, CR1, ABCA7 and TREM2 are the current genes of interest. In addition, risk prediction for AD and research on other related diseases are also popular research directions in this field. CONCLUSION This study conducted a comprehensive analysis of GWAS in AD and identified the current research hotspots and research trends. In addition, we also pointed out the shortcomings of current research and suggested future research directions. This study can provide researchers with information about the knowledge structure and emerging trends in the field of GWAS in AD and provide guidance for future research.
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Affiliation(s)
- Fanjing Kong
- School of Intelligent Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Tianyu Wu
- School of Acupuncture-Moxibustion and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Jingyi Dai
- School of Intelligent Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Jie Cai
- School of Intelligent Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Zhenwei Zhai
- School of Intelligent Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Zhishan Zhu
- School of Intelligent Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ying Xu
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Tao Sun
- School of Intelligent Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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3
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Naylor B, Anderson CNK, Hadfield M, Parkinson DH, Ahlstrom A, Hannemann A, Quilling CR, Cutler KJ, Denton RL, Adamson R, Angel TE, Burlett RS, Hafen PS, Dallon JC, Transtrum MK, Hyldahl RD, Price JC. Utilizing Nonequilibrium Isotope Enrichments to Dramatically Increase Turnover Measurement Ranges in Single Biopsy Samples from Humans. J Proteome Res 2022; 21:2703-2714. [PMID: 36099490 PMCID: PMC9639613 DOI: 10.1021/acs.jproteome.2c00380] [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: 07/06/2022] [Indexed: 11/30/2022]
Abstract
The synthesis of new proteins and the degradation of old proteins in vivo can be quantified in serial samples using metabolic isotope labeling to measure turnover. Because serial biopsies in humans are impractical, we set out to develop a method to calculate the turnover rates of proteins from single human biopsies. This method involved a new metabolic labeling approach and adjustments to the calculations used in previous work to calculate protein turnover. We demonstrate that using a nonequilibrium isotope enrichment strategy avoids the time dependent bias caused by variable lag in label delivery to different tissues observed in traditional metabolic labeling methods. Turnover rates are consistent for the same subject in biopsies from different labeling periods, and turnover rates calculated in this study are consistent with previously reported values. We also demonstrate that by measuring protein turnover we can determine where proteins are synthesized. In human subjects a significant difference in turnover rates differentiated proteins synthesized in the salivary glands versus those imported from the serum. We also provide a data analysis tool, DeuteRater-H, to calculate protein turnover using this nonequilibrium metabolic 2H2O method.
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Affiliation(s)
- Bradley
C. Naylor
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | | | - Marcus Hadfield
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - David H. Parkinson
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Austin Ahlstrom
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Austin Hannemann
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Chad R. Quilling
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Kyle J. Cutler
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Russell L. Denton
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Robert Adamson
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Thomas E. Angel
- In-vitro/In-vivo
Translation Platform Group, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Rebecca S. Burlett
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
| | - Paul S. Hafen
- Department
of Exercise Sciences, Brigham Young University, Provo, Utah 84602, United States
| | - John. C. Dallon
- Department
of Mathematics, Brigham Young University, Provo, Utah 84602, United States
| | - Mark K. Transtrum
- Department
of Physics and Astronomy, Brigham Young
University, Provo, Utah 84602, United States
| | - Robert D. Hyldahl
- Department
of Exercise Sciences, Brigham Young University, Provo, Utah 84602, United States
| | - John C. Price
- Department
of Chemistry and Biochemistry, Brigham Young
University, Provo, Utah 84602, United States
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4
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Gong X, Zhang H, Liu X, Liu Y, Liu J, Fapohunda FO, Lü P, Wang K, Tang M. Is liquid biopsy mature enough for the diagnosis of Alzheimer’s disease? Front Aging Neurosci 2022; 14:977999. [PMID: 35992602 PMCID: PMC9389010 DOI: 10.3389/fnagi.2022.977999] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 07/18/2022] [Indexed: 01/10/2023] Open
Abstract
The preclinical diagnosis and clinical practice for Alzheimer’s disease (AD) based on liquid biopsy have made great progress in recent years. As liquid biopsy is a fast, low-cost, and easy way to get the phase of AD, continual efforts from intense multidisciplinary studies have been made to move the research tools to routine clinical diagnostics. On one hand, technological breakthroughs have brought new detection methods to the outputs of liquid biopsy to stratify AD cases, resulting in higher accuracy and efficiency of diagnosis. On the other hand, diversiform biofluid biomarkers derived from cerebrospinal fluid (CSF), blood, urine, Saliva, and exosome were screened out and biologically verified. As a result, more detailed knowledge about the molecular pathogenesis of AD was discovered and elucidated. However, to date, how to weigh the reports derived from liquid biopsy for preclinical AD diagnosis is an ongoing question. In this review, we briefly introduce liquid biopsy and the role it plays in research and clinical practice. Then, we summarize the established fluid-based assays of the current state for AD diagnostic such as ELISA, single-molecule array (Simoa), Immunoprecipitation–Mass Spectrometry (IP–MS), liquid chromatography–MS, immunomagnetic reduction (IMR), multimer detection system (MDS). In addition, we give an updated list of fluid biomarkers in the AD research field. Lastly, the current outstanding challenges and the feasibility to use a stand-alone biomarker in the joint diagnostic strategy are discussed.
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Affiliation(s)
- Xun Gong
- Department of Rheumatology and Immunology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Hantao Zhang
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Xiaoyan Liu
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Yi Liu
- School of Life Sciences, Jiangsu University, Zhenjiang, China
- Institute of Animal Husbandry, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Junlin Liu
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | | | - Peng Lü
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Kun Wang
- Children’s Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, China
- *Correspondence: Kun Wang,
| | - Min Tang
- School of Life Sciences, Jiangsu University, Zhenjiang, China
- Min Tang,
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5
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Raha S, Ghosh A, Dutta D, Patel DR, Pahan K. Activation of PPARα enhances astroglial uptake and degradation of β-amyloid. Sci Signal 2021; 14:eabg4747. [PMID: 34699252 DOI: 10.1126/scisignal.abg4747] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Sumita Raha
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Arunava Ghosh
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Debashis Dutta
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Dhruv R Patel
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Kalipada Pahan
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA.,Division of Research and Development, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA
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6
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Gafson AR, Barthélemy NR, Bomont P, Carare RO, Durham HD, Julien JP, Kuhle J, Leppert D, Nixon RA, Weller RO, Zetterberg H, Matthews PM. Neurofilaments: neurobiological foundations for biomarker applications. Brain 2020; 143:1975-1998. [PMID: 32408345 DOI: 10.1093/brain/awaa098] [Citation(s) in RCA: 145] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 12/20/2019] [Accepted: 01/20/2020] [Indexed: 12/11/2022] Open
Abstract
Interest in neurofilaments has risen sharply in recent years with recognition of their potential as biomarkers of brain injury or neurodegeneration in CSF and blood. This is in the context of a growing appreciation for the complexity of the neurobiology of neurofilaments, new recognition of specialized roles for neurofilaments in synapses and a developing understanding of mechanisms responsible for their turnover. Here we will review the neurobiology of neurofilament proteins, describing current understanding of their structure and function, including recently discovered evidence for their roles in synapses. We will explore emerging understanding of the mechanisms of neurofilament degradation and clearance and review new methods for future elucidation of the kinetics of their turnover in humans. Primary roles of neurofilaments in the pathogenesis of human diseases will be described. With this background, we then will review critically evidence supporting use of neurofilament concentration measures as biomarkers of neuronal injury or degeneration. Finally, we will reflect on major challenges for studies of the neurobiology of intermediate filaments with specific attention to identifying what needs to be learned for more precise use and confident interpretation of neurofilament measures as biomarkers of neurodegeneration.
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Affiliation(s)
- Arie R Gafson
- Department of Brain Sciences, Imperial College, London, UK
| | - Nicolas R Barthélemy
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Pascale Bomont
- ATIP-Avenir team, INM, INSERM, Montpellier University, Montpellier, France
| | - Roxana O Carare
- Clinical Neurosciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Heather D Durham
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Québec, Canada
| | - Jean-Pierre Julien
- Department of Psychiatry and Neuroscience, Laval University, Quebec, Canada.,CERVO Brain Research Center, 2601 Chemin de la Canardière, Québec, QC, G1J 2G3, Canada
| | - Jens Kuhle
- Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital Basel, University of Basel, Basel, Switzerland
| | - David Leppert
- Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Ralph A Nixon
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, 10962, USA.,Departments of Psychiatry, New York University School of Medicine, New York, NY, 10016, USA.,Neuroscience Institute, New York University School of Medicine, New York, NY, 10016, USA.,Department of Cell Biology, New York University School of Medicine, New York, NY, 10016, USA
| | - Roy O Weller
- Clinical Neurosciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Henrik Zetterberg
- University College London Queen Square Institute of Neurology, London, UK.,UK Dementia Research Institute at University College London, London, UK.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Paul M Matthews
- Department of Brain Sciences, Imperial College, London, UK.,UK Dementia Research Institute at Imperial College, London
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7
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Krishnan N, Chen X, Donnelly-Roberts D, Mohler EG, Holtzman DM, Gopalakrishnan SM. Small Molecule Phenotypic Screen Identifies Novel Regulators of LDLR Expression. ACS Chem Biol 2020; 15:3262-3274. [PMID: 33270420 DOI: 10.1021/acschembio.0c00851] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alzheimer's Disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia. The current treatment options for AD are limited to ameliorating cognitive decline temporarily and not reversing or preventing the progression of dementia. Hence, more effective therapeutic strategies are needed to combat this devastating disease. The low-density lipoprotein receptor has been shown to modulate the neuronal metabolism of cholesterol and apolipoprotein E, a major genetic risk factor for AD. LDLR overexpression in mice has been shown to increase amyloid-β clearance and reduce amyloid deposition. We conducted a phenotypic screen to identify novel signaling pathways and targets that regulate LDLR expression in glial cells using an annotated compound library of approximately 29 000 compounds. The screen identified novel targets such as polo like kinase 1 (PLK1), activin receptor like kinase 5 (ALK5), and serotonin transporter (SERT). We used genetic, chemical biology and pathway analysis to confirm the target hypothesis. This work highlights that phenotypic screening is a promising strategy to identify novel mechanisms and targets for therapeutic intervention of complex neurodegenerative disorders.
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Affiliation(s)
- Navasona Krishnan
- AbbVie Inc., 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Xiaoying Chen
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
- Hope Center for Neurological Disorders, Washington University, St. Louis, Missouri 63110, United States
| | | | - Eric G. Mohler
- AbbVie Inc., 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - David M. Holtzman
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
- Hope Center for Neurological Disorders, Washington University, St. Louis, Missouri 63110, United States
- Charles F. and Joanne Knight Alzheimer’s Disease Research Center, Washington University, St. Louis, Missouri 63110, United States
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8
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Valdés A, Bergström Lind S. Mass Spectrometry-Based Analysis of Time-Resolved Proteome Quantification. Proteomics 2019; 20:e1800425. [PMID: 31652013 DOI: 10.1002/pmic.201800425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/20/2019] [Indexed: 11/09/2022]
Abstract
The aspect of time is essential in biological processes and thus it is important to be able to monitor signaling molecules through time. Proteins are key players in cellular signaling and they respond to many stimuli and change their expression in many time-dependent processes. Mass spectrometry (MS) is an important tool for studying proteins, including their posttranslational modifications and their interaction partners-both in qualitative and quantitative ways. In order to distinguish the different trends over time, proteins, modification sites, and interacting proteins must be compared between different time points, and therefore relative quantification is preferred. In this review, the progress and challenges for MS-based analysis of time-resolved proteome dynamics are discussed. Further, aspects on model systems, technologies, sampling frequencies, and presentation of the dynamic data are discussed.
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Affiliation(s)
- Alberto Valdés
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Ctra. Madrid-Barcelona, Km. 33.600, 28871, Alcalá de Henares, Madrid, Spain
| | - Sara Bergström Lind
- Department of Chemistry-BMC, Analytical Chemistry, Uppsala University, Box 599, 75124, Uppsala, Sweden
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9
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Paterson RW, Gabelle A, Lucey BP, Barthélemy NR, Leckey CA, Hirtz C, Lehmann S, Sato C, Patterson BW, West T, Yarasheski K, Rohrer JD, Wildburger NC, Schott JM, Karch CM, Wray S, Miller TM, Elbert DL, Zetterberg H, Fox NC, Bateman RJ. SILK studies - capturing the turnover of proteins linked to neurodegenerative diseases. Nat Rev Neurol 2019; 15:419-427. [PMID: 31222062 PMCID: PMC6876864 DOI: 10.1038/s41582-019-0222-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2019] [Indexed: 01/12/2023]
Abstract
Alzheimer disease (AD) is one of several neurodegenerative diseases characterized by dysregulation, misfolding and accumulation of specific proteins in the CNS. The stable isotope labelling kinetics (SILK) technique is based on generating amino acids labelled with naturally occurring stable (that is, nonradioactive) isotopes of carbon and/or nitrogen. These labelled amino acids can then be incorporated into proteins, enabling rates of protein production and clearance to be determined in vivo and in vitro without the use of radioactive or chemical labels. Over the past decade, SILK studies have been used to determine the turnover of key pathogenic proteins amyloid-β (Aβ), tau and superoxide dismutase 1 (SOD1) in the cerebrospinal fluid of healthy individuals, patients with AD and those with other neurodegenerative diseases. These studies led to the identification of several factors that alter the production and/or clearance of these proteins, including age, sleep and disease-causing genetic mutations. SILK studies have also been used to measure Aβ turnover in blood and within brain tissue. SILK studies offer the potential to elucidate the mechanisms underlying various neurodegenerative disease mechanisms, including neuroinflammation and synaptic dysfunction, and to demonstrate target engagement of novel disease-modifying therapies.
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Affiliation(s)
- Ross W Paterson
- Dementia Research Centre, Department of Neurodegeneration, University College London (UCL) Institute of Neurology, London, UK.
| | - Audrey Gabelle
- Department of Neurology, Memory Research and Resources Centre, Centre Hospitalier Universitaire (CHU), Montpellier, France
- University of Montpellier, Campus Universitaire du Triolet, Montpellier, France
- INSERM U1163, Institut de Médecine Régénérative, Saint Eloi Hospital, Montpellier, France
| | - Brendan P Lucey
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Nicolas R Barthélemy
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Claire A Leckey
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London, UK
| | - Christophe Hirtz
- Department of Neurology, Memory Research and Resources Centre, Centre Hospitalier Universitaire (CHU), Montpellier, France
- University of Montpellier, Campus Universitaire du Triolet, Montpellier, France
- INSERM U1163, Institut de Médecine Régénérative, Saint Eloi Hospital, Montpellier, France
| | - Sylvain Lehmann
- Department of Neurology, Memory Research and Resources Centre, Centre Hospitalier Universitaire (CHU), Montpellier, France
- University of Montpellier, Campus Universitaire du Triolet, Montpellier, France
- INSERM U1163, Institut de Médecine Régénérative, Saint Eloi Hospital, Montpellier, France
| | - Chihiro Sato
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Bruce W Patterson
- Department of Medicine, Washington University School of Medicine, St Louis, MO, USA
| | - Tim West
- C2N Diagnostics, Center for Emerging Technologies, St Louis, MO, USA
| | - Kevin Yarasheski
- C2N Diagnostics, Center for Emerging Technologies, St Louis, MO, USA
| | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegeneration, University College London (UCL) Institute of Neurology, London, UK
| | - Norelle C Wildburger
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Jonathan M Schott
- Dementia Research Centre, Department of Neurodegeneration, University College London (UCL) Institute of Neurology, London, UK
| | - Celeste M Karch
- Department of Psychiatry, Washington University, St Louis, MO, USA
| | - Selina Wray
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London, UK
| | - Timothy M Miller
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Donald L Elbert
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, TX, USA
| | - Henrik Zetterberg
- Dementia Research Centre, Department of Neurodegeneration, University College London (UCL) Institute of Neurology, London, UK
- UK Dementia Research Institute at University College London (UCL), London, UK
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden
| | - Nick C Fox
- Dementia Research Centre, Department of Neurodegeneration, University College London (UCL) Institute of Neurology, London, UK
| | - Randall J Bateman
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
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10
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Pacheco-Quinto J, Eckman CB, Eckman EA. Major amyloid-β-degrading enzymes, endothelin-converting enzyme-2 and neprilysin, are expressed by distinct populations of GABAergic interneurons in hippocampus and neocortex. Neurobiol Aging 2016; 48:83-92. [PMID: 27644077 DOI: 10.1016/j.neurobiolaging.2016.08.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/10/2016] [Accepted: 08/12/2016] [Indexed: 01/17/2023]
Abstract
Impaired clearance of amyloid-β peptide (Aβ) has been postulated to significantly contribute to the amyloid accumulation typical of Alzheimer's disease. Among the enzymes known to degrade Aβ in vivo are endothelin-converting enzyme (ECE)-1, ECE-2, and neprilysin (NEP), and evidence suggests that they regulate independent pools of Aβ that may be functionally significant. To better understand the differential regulation of Aβ concentration by its physiological degrading enzymes, we characterized the cell and region-specific expression pattern of ECE-1, ECE-2, and NEP by in situ hybridization and immunohistochemistry in brain areas relevant to Alzheimer's disease. In contrast to the broader distribution of ECE-1, ECE-2 and NEP were found enriched in GABAergic neurons. ECE-2 was majorly expressed by somatostatin-expressing interneurons and was active in isolated synaptosomes. NEP messenger RNA was found mainly in parvalbumin-expressing interneurons, with NEP protein localized to perisomatic parvalbuminergic synapses. The identification of somatostatinergic and parvalbuminergic synapses as hubs for Aβ degradation is consistent with the possibility that Aβ may have a physiological function related to the regulation of inhibitory signaling.
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Affiliation(s)
- Javier Pacheco-Quinto
- Atlantic Health System, Morristown, NJ, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA
| | - Christopher B Eckman
- Atlantic Health System, Morristown, NJ, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA
| | - Elizabeth A Eckman
- Atlantic Health System, Morristown, NJ, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA.
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11
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Li G, Kim C, Kim J, Yoon H, Zhou H, Kim J. Common Pesticide, Dichlorodiphenyltrichloroethane (DDT), Increases Amyloid-β Levels by Impairing the Function of ABCA1 and IDE: Implication for Alzheimer's Disease. J Alzheimers Dis 2016; 46:109-22. [PMID: 25720399 DOI: 10.3233/jad-150024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
While early-onset familial Alzheimer's disease (AD) is caused by a genetic mutation, the vast majority of late-onset AD is likely caused by the combination of genetic and environmental factors. Unlike genetic studies, potential environmental factors affecting AD pathogenesis have not yet been thoroughly investigated. Among environmental factors, pesticides seem to be one of critical environmental contributors to late-onset AD. Recent studies reported that the serum and brains of AD patients have dramatically higher levels of a metabolite of dichlorodiphenyltrichloroethane (DDT). While these epidemiological studies provided initial clues to the environmental risks potentially contributing to disease pathogenesis, a functional approach is required to determine whether they actually have a causal role in disease development. In our study, we addressed this critical knowledge gap by investigating possible mechanisms by which DDT affects amyloid-β (Aβ) levels. We treated H4-AβPPswe or H4 cells with DDT to analyze its effect on Aβ metabolism using Aβ production, clearance, and degradation assays. We found that DDT significantly increased the levels of amyloid-β protein precursor (AβPP) and β-site AβPP-cleaving enzyme1 (BACE1), affecting Aβ synthesis pathway in H4-AβPPswe cells. Additionally, DDT impaired the clearance and extracellular degradation of Aβ peptides. Most importantly, we identified for the first time that ATP-binding cassette transporter A1 (ABCA1) and insulin-degrading enzyme (IDE) are the downstream target genes adversely affected by DDT. Our findings provide insight into the molecular mechanisms by which DDT exposure may increase the risk of AD, and it further supports that ABCA1 and IDE may be potential therapeutic targets.
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Affiliation(s)
- Gongbo Li
- Department of Neurology, Daping Hospital, Third Military Medical University, Chongqing, China.,Department of Neuroscience, Mayo Clinic College of Medicine, Jacksonville, FL, USA
| | - Chaeyoung Kim
- Department of Neuroscience, Mayo Clinic College of Medicine, Jacksonville, FL, USA
| | - Jaekwang Kim
- Department of Neuroscience, Mayo Clinic College of Medicine, Jacksonville, FL, USA
| | - Hyejin Yoon
- Department of Neuroscience, Mayo Clinic College of Medicine, Jacksonville, FL, USA.,Neurobiology of Disease Graduate Program, Mayo Graduate School, Jacksonville, FL, USA
| | - Huadong Zhou
- Department of Neurology, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Jungsu Kim
- Department of Neuroscience, Mayo Clinic College of Medicine, Jacksonville, FL, USA.,Neurobiology of Disease Graduate Program, Mayo Graduate School, Jacksonville, FL, USA
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12
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Yamada K, Patel TK, Hochgräfe K, Mahan TE, Jiang H, Stewart FR, Mandelkow EM, Holtzman DM. Analysis of in vivo turnover of tau in a mouse model of tauopathy. Mol Neurodegener 2015; 10:55. [PMID: 26502977 PMCID: PMC4621881 DOI: 10.1186/s13024-015-0052-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 10/21/2015] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Intracellular accumulation of tau as neurofibrillary tangles (NFTs) is the hallmark of Alzheimer's disease (AD) as well as in other tauopathies. Tau is present not only in the cytoplasm but also in the extracellular space such as cerebrospinal fluid (CSF) and brain interstitial fluid (ISF). Although clearance is one critical parameter leading to such intracellular/extracellular tau accumulation, in vivo turnover of tau has not been well characterized. The current study has attempted to precisely determine in vivo turnover rates of tau utilizing tet-off regulatable mice. In particular, we assessed intracellular tau and extracellular tau, soluble tau, insoluble tau and phosphorylated tau at certain sites utilizing a combination of in vivo microdialysis, biochemical analysis and specific ELISAs recognizing each species. To examine the effect of a tauopathy-associated mutation on tau clearance, half-lives of various tau species were compared between the mice with a FTDP-17 mutation that induces β-sheet formation, ΔK280 mutation (pro-aggregant mice) and control mice with additional β-sheet breaking mutations (anti-aggregant mice). RESULTS Here we report that tau is metabolized at much slower turnover rates in vivo than in cell culture. We found that insoluble tau in pro-aggregant mice had a significantly slower half-life (t1/2 = ~34.2 days) than soluble tau (t1/2 = ~9.7 days). In contrast, soluble tau phosphorylated in the proline rich region was cleared faster than total soluble tau. When comparing pro-aggregant mice to anti-agregant mice, turnover rates of soluble tau species were not significantly different. CONCLUSIONS The current study provides a comprehensive description of in vivo turnover of various tau species present in mice that express human tau. The turnover rate of soluble tau was not significantly altered between pro-aggregant mice and anti-aggregant mice. This suggests that altered conformation by ΔK280 does not have a major impact on clearance pathways for soluble tau. In contrast, different tau species displayed different half-lives. Turnover was significantly delayed for insoluble tau whereas it was accelerated for soluble tau phosphorylated in the proline rich region. These differences in susceptibilities to clearance suggest that aggregation and phosphorylation influences tau clearance which may be important in tau pathogenesis.
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Affiliation(s)
- Kaoru Yamada
- Department of Neuropathology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan.
| | - Tirth K Patel
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, Missouri, 63110, USA.
| | - Katja Hochgräfe
- MPI for Neurological Research, Hamburg Outstation, c/o DESY, Notkestr. 85, 22607, Hamburg, Germany.
| | - Thomas E Mahan
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, Missouri, 63110, USA.
| | - Hong Jiang
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, Missouri, 63110, USA.
| | - Floy R Stewart
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, Missouri, 63110, USA.
| | - Eva-Maria Mandelkow
- MPI for Neurological Research, Hamburg Outstation, c/o DESY, Notkestr. 85, 22607, Hamburg, Germany. .,DZNE (German Ctr Neurodegen. Diseases), Ludwig-Erhard-Allee 2, 53175, Bonn, Germany. .,CAESAR Research Center, Ludwig-Erhard-Allee 2, 53175, Bonn, Germany.
| | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, Missouri, 63110, USA.
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13
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Beyond classical derivatization: analyte ‘derivatives’ in the bioanalysis of endogenous and exogenous compounds. Bioanalysis 2015; 7:2501-13. [DOI: 10.4155/bio.15.171] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The analysis of endogenous and exogenous analytes in biological matrices presents several challenges to the bioanalyst. These analytes are often present at low concentrations, typically in complex matrices, and may have physicochemical properties that are not amenable to LC–MS analysis. The bioanalyst thus relies heavily on the formation of analyte derivatives for the efficient quantification of these compounds. These derivatives are also critically employed to derive information on the biology of living systems, potential drug or disease targets, and biomarkers of drug efficacy, safety, or disease progression. In this perspective, we demonstrate how analyte derivatives are applied in modern bioanalytical workflows and we discuss the potential use of these derivatives in the future.
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14
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Vandal M, Bourassa P, Calon F. Can insulin signaling pathways be targeted to transport Aβ out of the brain? Front Aging Neurosci 2015; 7:114. [PMID: 26136681 PMCID: PMC4468380 DOI: 10.3389/fnagi.2015.00114] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 05/29/2015] [Indexed: 12/11/2022] Open
Abstract
Although the causal role of Amyloid-β (Aβ) in Alzheimer’s disease (AD) is unclear, it is still reasonable to expect that lowering concentrations of Aβ in the brain may decrease the risk of developing the neurocognitive symptoms of the disease. Brain capillary endothelial cells forming the blood-brain barrier (BBB) express transporters regulating the efflux of Aβ out of the cerebral tissue. Age-related BBB dysfunctions, that have been identified in AD patients, might impair Aβ clearance from the brain. Thus, targeting BBB outward transport systems has been suggested as a way to stimulate the clearance of Aβ from the brain. Recent data indicate that the increase in soluble brain Aβ and behavioral impairments in 3×Tg-AD mice generated by months of intake of a high-fat diet can be acutely reversed by the administration of a single dose of insulin. A concomitant increase in plasma Aβ suggests that clearance from the brain through the BBB is a likely mechanism for this rapid effect of insulin. Here, we review how BBB insulin response pathways could be stimulated to decrease brain Aβ concentrations and improve cognitive performance, at least on the short term.
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Affiliation(s)
- Milene Vandal
- Faculté de Pharmacie, Université Laval Quebec, QC, Canada ; Axe Neurosciences, Centre de Recherche du Centre Hospitalier de l'Université Laval (CHUL) Québec, QC, Canada ; Institut des Nutraceutiques et des Aliments Fonctionnels, Université Laval Québec, QC, Canada
| | - Philippe Bourassa
- Faculté de Pharmacie, Université Laval Quebec, QC, Canada ; Axe Neurosciences, Centre de Recherche du Centre Hospitalier de l'Université Laval (CHUL) Québec, QC, Canada ; Institut des Nutraceutiques et des Aliments Fonctionnels, Université Laval Québec, QC, Canada
| | - Frédéric Calon
- Faculté de Pharmacie, Université Laval Quebec, QC, Canada ; Axe Neurosciences, Centre de Recherche du Centre Hospitalier de l'Université Laval (CHUL) Québec, QC, Canada ; Institut des Nutraceutiques et des Aliments Fonctionnels, Université Laval Québec, QC, Canada
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15
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Frieden C. ApoE: the role of conserved residues in defining function. Protein Sci 2014; 24:138-44. [PMID: 25377861 DOI: 10.1002/pro.2597] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 10/24/2014] [Accepted: 10/29/2014] [Indexed: 01/31/2023]
Abstract
The amino acid sequences of apolipoprotein E (apoE) from 63 different mammalian species have been downloaded from the protein database. The sequences were compared to human apoE4 to determine conserved and non-conserved sequences of amino acids. ApoE4 is the major risk factor for the development of late onset Alzheimer's disease while apoE3, which differs from apoE4 by a single amino acid change at position 112, poses little or no risk for the development of this disease. Thus, the two proteins appear to be structurally and functionally different. Seven highly conserved regions, representing approximately 47 amino acids (of 299) have been found. These regions are distributed throughout the protein and reflect ligand binding sites as well as regions proposed to be involved in the propagation of the cysteine-arginine change at position 112 to distant regions of the protein in the N- and C-terminal domains. Highly non-conserved regions are at the N- and C-terminal ends of the apoE protein.
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Affiliation(s)
- Carl Frieden
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri, 63110
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16
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Frieden C, Garai K. Concerning the structure of apoE. Protein Sci 2013; 22:1820-5. [PMID: 24115173 DOI: 10.1002/pro.2379] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 09/12/2013] [Indexed: 12/16/2022]
Abstract
Apolipoprotein E (apoE), first described in 1973, is a truly fascinating protein. While studies initially focused on its role in cholesterol and lipid metabolism, one apoE isoform (apoE4) is a major risk factor for development of late onset Alzheimer's disease. Yet the difference between apoE3, the common form, and apoE4 is a single amino acid of the 299 in this 34 kDa protein. Structure determination of the two domain full length apoE3 protein was only accomplished in 2011 and supports the notion that mutations in the N-terminal domain can be propagated through the structure to the C-terminal domain. Understanding the structural differences between apoE3 and apoE4 is critical for finding ways to modulate the deleterious effect of apoE4.
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Affiliation(s)
- Carl Frieden
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri, 63110
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17
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Previs SF, McLaren DG, Wang SP, Stout SJ, Zhou H, Herath K, Shah V, Miller PL, Wilsie L, Castro-Perez J, Johns DG, Cleary MA, Roddy TP. New methodologies for studying lipid synthesis and turnover: looking backwards to enable moving forwards. Biochim Biophys Acta Mol Basis Dis 2013; 1842:402-13. [PMID: 23707557 DOI: 10.1016/j.bbadis.2013.05.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/11/2013] [Accepted: 05/13/2013] [Indexed: 12/26/2022]
Abstract
Our ability to understand the pathogenesis of problems surrounding lipid accretion requires attention towards quantifying lipid kinetics. In addition, studies of metabolic flux should also help unravel mechanisms that lead to imbalances in inter-organ lipid trafficking which contribute to dyslipidemia and/or peripheral lipid accumulation (e.g. hepatic fat deposits). This review aims to outline the development and use of novel methods for studying lipid kinetics in vivo. Although our focus is directed towards some of the approaches that are currently reported in the literature, we include a discussion of the older literature in order to put "new" methods in better perspective and inform readers of valuable historical research. Presumably, future advances in understanding lipid dynamics will benefit from a careful consideration of the past efforts, where possible we have tried to identify seminal papers or those that provide clear data to emphasize essential points. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.
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Affiliation(s)
- Stephen F Previs
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
| | - David G McLaren
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Sheng-Ping Wang
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Steven J Stout
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Haihong Zhou
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Kithsiri Herath
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Vinit Shah
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Paul L Miller
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Larissa Wilsie
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Jose Castro-Perez
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Douglas G Johns
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Michele A Cleary
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Thomas P Roddy
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
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18
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Ly S, Altman R, Petrlova J, Lin Y, Hilt S, Huser T, Laurence TA, Voss JC. Binding of apolipoprotein E inhibits the oligomer growth of amyloid-β peptide in solution as determined by fluorescence cross-correlation spectroscopy. J Biol Chem 2013; 288:11628-35. [PMID: 23430745 DOI: 10.1074/jbc.m112.411900] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
One of the primary neuropathological hallmarks of Alzheimer disease is the presence of extracellular amyloid plaques resulting from the aggregation of amyloid-β (Aβ) peptides. The intrinsic disorder of the Aβ peptide drives self-association and progressive reordering of the conformation in solution, and this dynamic distribution of Aβ complicates biophysical studies. This property poses a challenge for understanding the interaction of Aβ with apolipoprotein E (apoE). ApoE plays a pivotal role in the aggregation and clearance of Aβ peptides in the brain, and the ε4 allele of APOE is the most significant known genetic modulator of Alzheimer risk. Understanding the interaction between apoE and Aβ will provide insight into the mechanism by which different apoE isoforms determine Alzheimer disease risk. Here we applied alternating laser excitation fluorescence cross-correlation spectroscopy to observe the single molecule interaction of Aβ with apoE in the hydrated state. The diffusion time of freely diffusing Aβ in the absence of apoE shows significant self-aggregation, whereas in the presence of apoE, binding of the protein results in a more stable complex. These results show that apoE slows down the oligomerization of Aβ in solution and provide direct insight into the process by which apoE influences the deposition and clearance of Aβ peptides in the brain. Furthermore, by developing an approach to remove signals arising from very large Aβ aggregates, we show that real-time single particle observations provide access to information regarding the fraction of apoE bound and the stoichiometry of apoE and Aβ in the complex.
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Affiliation(s)
- Sonny Ly
- Physical and Life Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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19
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Tai LM, Bilousova T, Jungbauer L, Roeske SK, Youmans KL, Yu C, Poon WW, Cornwell LB, Miller CA, Vinters HV, Van Eldik LJ, Fardo DW, Estus S, Bu G, Gylys KH, Ladu MJ. Levels of soluble apolipoprotein E/amyloid-β (Aβ) complex are reduced and oligomeric Aβ increased with APOE4 and Alzheimer disease in a transgenic mouse model and human samples. J Biol Chem 2013; 288:5914-26. [PMID: 23293020 DOI: 10.1074/jbc.m112.442103] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Human apolipoprotein E (apoE) isoforms may differentially modulate amyloid-β (Aβ) levels. Evidence suggests physical interactions between apoE and Aβ are partially responsible for these functional effects. However, the apoE/Aβ complex is not a single static structure; rather, it is defined by detection methods. Thus, literature results are inconsistent and difficult to interpret. An ELISA was developed to measure soluble apoE/Aβ in a single, quantitative method and was used to address the hypothesis that reduced levels of soluble apoE/Aβ and an increase in soluble Aβ, specifically oligomeric Aβ (oAβ), are associated with APOE4 and AD. Previously, soluble Aβ42 and oAβ levels were greater with APOE4 compared with APOE2/APOE3 in hippocampal homogenates from EFAD transgenic mice (expressing five familial AD mutations and human apoE isoforms). In this study, soluble apoE/Aβ levels were lower in E4FAD mice compared with E2FAD and E3FAD mice, thus providing evidence that apoE/Aβ levels isoform-specifically modulate soluble oAβ clearance. Similar results were observed in soluble preparations of human cortical synaptosomes; apoE/Aβ levels were lower in AD patients compared with controls and lower with APOE4 in the AD cohort. In human CSF, apoE/Aβ levels were also lower in AD patients and with APOE4 in the AD cohort. Importantly, although total Aβ42 levels decreased in AD patients compared with controls, oAβ levels increased and were greater with APOE4 in the AD cohort. Overall, apoE isoform-specific formation of soluble apoE/Aβ modulates oAβ levels, suggesting a basis for APOE4-induced AD risk and a mechanistic approach to AD biomarkers.
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Affiliation(s)
- Leon M Tai
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, Illinois 60612, USA
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20
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Ridnour LA, Dhanapal S, Hoos M, Wilson J, Lee J, Cheng RYS, Brueggemann EE, Hines HB, Wilcock DM, Vitek MP, Wink DA, Colton CA. Nitric oxide-mediated regulation of β-amyloid clearance via alterations of MMP-9/TIMP-1. J Neurochem 2012; 123:736-49. [PMID: 23016931 DOI: 10.1111/jnc.12028] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/06/2012] [Accepted: 09/15/2012] [Indexed: 01/22/2023]
Abstract
Fibrillar amyloid plaques are largely composed of amyloid-beta (Aβ) peptides that are metabolized into products, including Aβ1-16, by proteases including matrix metalloproteinase 9 (MMP-9). The balance between production and degradation of Aβ proteins is critical to amyloid accumulation and resulting disease. Regulation of MMP-9 and its endogenous inhibitor tissue inhibitor of metalloproteinase (TIMP)-1 by nitric oxide (NO) has been shown. We hypothesize that nitric oxide synthase (NOS2) protects against Alzheimer's disease pathology by increasing amyloid clearance through NO regulation of MMP-9/TIMP-1 balance. We show NO-mediated increased MMP-9/TIMP-1 ratios enhanced the degradation of fibrillar Aβ in vitro, which was abolished when silenced for MMP-9 protein translation. The in vivo relationship between MMP-9, NO and Aβ degradation was examined by comparing an Alzheimer's disease mouse model that expresses NOS2 with a model lacking NOS2. To quantitate MMP-9 mediated changes, we generated an antibody recognizing the Aβ1-16 fragment, and used mass spectrometry multi-reaction monitoring assay for detection of immunoprecipitated Aβ1-16 peptides. Aβ1-16 levels decreased in brain lysates lacking NOS2 when compared with strains that express human amyloid precursor protein on the NOS2 background. TIMP-1 increased in the APPSwDI/NOS2(-/-) mice with decreased MMP activity and increased amyloid burden, thereby supporting roles for NO in the regulation of MMP/TIMP balance and plaque clearance.
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Affiliation(s)
- Lisa A Ridnour
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
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