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McQuade A, Blurton-Jones M. Microglia in Alzheimer's Disease: Exploring How Genetics and Phenotype Influence Risk. J Mol Biol 2019; 431:1805-1817. [PMID: 30738892 PMCID: PMC6475606 DOI: 10.1016/j.jmb.2019.01.045] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/29/2019] [Accepted: 01/29/2019] [Indexed: 01/25/2023]
Abstract
Research into the function of microglia has dramatically accelerated during the last few years, largely due to recent genetic findings implicating microglia in virtually every neurodegenerative disorder. In Alzheimer's disease (AD), a majority of risk loci discovered through genome-wide association studies were found in or near genes expressed most highly in microglia leading to the hypothesis that microglia play a much larger role in disease progression than previously thought. From this body of work produced in the last several years, we find that almost every function of microglia has been proposed to influence the progression of AD from altered phagocytosis and synaptic pruning to cytokine secretion and changes in trophic support. By studying key Alzheimer's risk genes such as TREM2, CD33, ABCA7, and MS4A6A, we will be able to distinguish true disease-modulatory pathways from the full range of microglial-related functions. To successfully carry out these experiments, more advanced microglial models are needed. Microglia are quite sensitive to their local environment, suggesting the need to more fully recapitulate an in vivo environment to study this highly plastic cell type. Likely only by combining the above approaches will the field fully elucidate the molecular pathways that regulate microglia and influence neurodegeneration, in turn uncovering potential new targets for future therapeutic development.
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Affiliation(s)
- Amanda McQuade
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Mathew Blurton-Jones
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA.
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52
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den Dekker HT, Burrows K, Felix JF, Salas LA, Nedeljkovic I, Yao J, Rifas-Shiman SL, Ruiz-Arenas C, Amin N, Bustamante M, DeMeo DL, Henderson AJ, Howe CG, Hivert MF, Ikram MA, de Jongste JC, Lahousse L, Mandaviya PR, van Meurs JB, Pinart M, Sharp GC, Stolk L, Uitterlinden AG, Anto JM, Litonjua AA, Breton CV, Brusselle GG, Sunyer J, Smith GD, Relton CL, Jaddoe VWV, Duijts L. Newborn DNA-methylation, childhood lung function, and the risks of asthma and COPD across the life course. Eur Respir J 2019; 53:13993003.01795-2018. [PMID: 30765504 DOI: 10.1183/13993003.01795-2018] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/08/2019] [Indexed: 01/13/2023]
Abstract
RATIONALE We aimed to identify differentially methylated regions (DMRs) in cord blood DNA associated with childhood lung function, asthma and chronic obstructive pulmonary disease (COPD) across the life course. METHODS We meta-analysed epigenome-wide data of 1688 children from five cohorts to identify cord blood DMRs and their annotated genes, in relation to forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity (FVC) ratio and forced expiratory flow at 75% of FVC at ages 7-13 years. Identified DMRs were explored for associations with childhood asthma, adult lung function and COPD, gene expression and involvement in biological processes. RESULTS We identified 59 DMRs associated with childhood lung function, of which 18 were associated with childhood asthma and nine with COPD in adulthood. Genes annotated to the top 10 identified DMRs were HOXA5, PAOX, LINC00602, ABCA7, PER3, CLCA1, VENTX, NUDT12, PTPRN2 and TCL1A. Differential gene expression in blood was observed for 32 DMRs in childhood and 18 in adulthood. Genes related with 16 identified DMRs were associated with respiratory developmental or pathogenic pathways. INTERPRETATION Our findings suggest that the epigenetic status of the newborn affects respiratory health and disease across the life course.
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Affiliation(s)
- Herman T den Dekker
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Pediatrics, Division of Respiratory Medicine and Allergology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,These authors contributed equally
| | - Kimberley Burrows
- MRC Integrative Epidemiology Unit, University of Bristol, UK School of Social and Community Medicine, University of Bristol, Bristol, UK.,These authors contributed equally
| | - Janine F Felix
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Pediatrics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,These authors contributed equally
| | - Lucas A Salas
- ISGLobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.,Dept of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - Ivana Nedeljkovic
- Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jin Yao
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Sheryl L Rifas-Shiman
- Obesity Prevention Program, Dept of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA
| | - Carlos Ruiz-Arenas
- ISGLobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - N Amin
- Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Mariona Bustamante
- ISGLobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain.,Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Dawn L DeMeo
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - A John Henderson
- MRC Integrative Epidemiology Unit, University of Bristol, UK School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Caitlin G Howe
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Marie-France Hivert
- Obesity Prevention Program, Dept of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA
| | - M Arfan Ikram
- Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Johan C de Jongste
- Dept of Pediatrics, Division of Respiratory Medicine and Allergology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Lies Lahousse
- Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Pooja R Mandaviya
- Dept of Clinical Chemistry, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Joyce B van Meurs
- Dept of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Mariona Pinart
- ISGLobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain.,IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | - Gemma C Sharp
- MRC Integrative Epidemiology Unit, University of Bristol, UK School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Lisette Stolk
- Dept of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Netherlands Consortium for Healthy Ageing (NCHA), Erasmus MC, University Medical Center Rotterdam, The Netherlands
| | - André G Uitterlinden
- Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Netherlands Consortium for Healthy Ageing (NCHA), Erasmus MC, University Medical Center Rotterdam, The Netherlands
| | - Josep M Anto
- ISGLobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain.,IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | - Augusto A Litonjua
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Carrie V Breton
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Guy G Brusselle
- Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA.,Dept of Respiratory Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jordi Sunyer
- ISGLobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain.,IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | - George Davey Smith
- MRC Integrative Epidemiology Unit, University of Bristol, UK School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Caroline L Relton
- MRC Integrative Epidemiology Unit, University of Bristol, UK School of Social and Community Medicine, University of Bristol, Bristol, UK.,These authors contributed equally
| | - Vincent W V Jaddoe
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Dept of Pediatrics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,These authors contributed equally
| | - Liesbeth Duijts
- Dept of Pediatrics, Division of Respiratory Medicine and Allergology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands .,Dept of Pediatrics, Division of Neonatology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,These authors contributed equally
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Takatori S, Wang W, Iguchi A, Tomita T. Genetic Risk Factors for Alzheimer Disease: Emerging Roles of Microglia in Disease Pathomechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1118:83-116. [PMID: 30747419 DOI: 10.1007/978-3-030-05542-4_5] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The accumulation of aggregated amyloid β (Aβ) peptides in the brain is deeply involved in Alzheimer disease (AD) pathogenesis. Mutations in APP and presenilins play major roles in Aβ pathology in rare autosomal-dominant forms of AD, whereas pathomechanisms of sporadic AD, accounting for the majority of cases, remain unknown. In this chapter, we review current knowledge on genetic risk factors of AD, clarified by recent advances in genome analysis technology. Interestingly, TREM2 and many genes associated with disease risk are predominantly expressed in microglia, suggesting that these risk factors are involved in pathogenicity through common mechanisms involving microglia. Therefore, we focus on factors closely associated with microglia and discuss their possible roles in pathomechanisms of AD. Furthermore, we review current views on the pathological roles of microglia and emphasize the importance of microglial changes in response to Aβ deposition and mechanisms underlying the phenotypic changes. Importantly, functional outcomes of microglial activation can be both protective and deleterious to neurons. We further describe the involvement of microglia in tau pathology and the activation of other glial cells. Through these topics, we shed light on microglia as a promising target for drug development for AD and other neurological disorders.
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Affiliation(s)
- Sho Takatori
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Wenbo Wang
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Akihiro Iguchi
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Taisuke Tomita
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.
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Bisht K, Sharma K, Tremblay MÈ. Chronic stress as a risk factor for Alzheimer's disease: Roles of microglia-mediated synaptic remodeling, inflammation, and oxidative stress. Neurobiol Stress 2018; 9:9-21. [PMID: 29992181 PMCID: PMC6035903 DOI: 10.1016/j.ynstr.2018.05.003] [Citation(s) in RCA: 206] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 02/23/2018] [Accepted: 05/14/2018] [Indexed: 02/07/2023] Open
Abstract
Microglia are the predominant immune cells of the central nervous system (CNS) that exert key physiological roles required for maintaining CNS homeostasis, notably in response to chronic stress, as well as mediating synaptic plasticity, learning and memory. The repeated exposure to stress confers a higher risk of developing neurodegenerative diseases including sporadic Alzheimer's disease (AD). While microglia have been causally linked to amyloid beta (Aβ) accumulation, tau pathology, neurodegeneration, and synaptic loss in AD, they were also attributed beneficial roles, notably in the phagocytic elimination of Aβ. In this review, we discuss the interactions between chronic stress and AD pathology, overview the roles played by microglia in AD, especially focusing on chronic stress as an environmental risk factor modulating their function, and present recently-described microglial phenotypes associated with neuroprotection in AD. These microglial phenotypes observed under both chronic stress and AD pathology may provide novel opportunities for the development of better-targeted therapeutic interventions.
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Key Words
- ABCA7, ATP-binding cassette transporter A7
- AD, Alzheimer's disease
- APOE, Apolipoprotein E
- APP, amyloid precursor protein
- Alzheimer's disease
- Aβ, Amyloid beta
- BDNF, brain derived neurotrophic factor
- CD11b, cluster of differentiation molecule 11B
- CD33, cluster of differentiation 33
- CNS, central nervous system
- CR, complement receptor
- CRF, corticotropin releasing factor
- DAM, disease associated microglia
- DAP12, DNAX-activation protein 12
- Dark microglia
- FAD, Familial Alzheimer's disease
- FCRLS, Fc receptor-like S scavenger receptor
- GR, glucocorticoid receptor
- HPA axis, hypothalamic pituitary adrenocortical axis
- IBA1, ionized calcium-binding adapter molecule 1
- IL, interleukin
- LTP, long-term potentiation
- MGnD, microglia with a neurodegenerative phenotype
- MR, mineralocorticoid receptor
- Microglia
- Microglial phenotypes
- NADPH, nicotinamide adenine dinucleotide phosphate
- NFT, neurofibrillary tangles
- Neurodegeneration
- Neuroinflammation
- PS, presenilin
- ROS, reactive oxygen species
- Stress
- Synaptic remodeling
- TGFβ, transforming growth factor β
- TLR, Toll-like receptors
- TMEM119, transmembrane protein 119
- TNFα, tumor necrosis factor-α
- TREM2, triggering receptor expressed in myeloid cells 2
- TYROBP, TYRO protein tyrosine kinase binding protein
- mPFC, medial prefrontal cortex
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Affiliation(s)
- Kanchan Bisht
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
| | - Kaushik Sharma
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec, QC, Canada
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Moustafa AA, Hassan M, Hewedi DH, Hewedi I, Garami JK, Al Ashwal H, Zaki N, Seo SY, Cutsuridis V, Angulo SL, Natesh JY, Herzallah MM, Frydecka D, Misiak B, Salama M, Mohamed W, El Haj M, Hornberger M. Genetic underpinnings in Alzheimer's disease - a review. Rev Neurosci 2018; 29:21-38. [PMID: 28949931 DOI: 10.1515/revneuro-2017-0036] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 06/10/2017] [Indexed: 12/13/2022]
Abstract
In this review, we discuss the genetic etiologies of Alzheimer's disease (AD). Furthermore, we review genetic links to protein signaling pathways as novel pharmacological targets to treat AD. Moreover, we also discuss the clumps of AD-m ediated genes according to their single nucleotide polymorphism mutations. Rigorous data mining approaches justified the significant role of genes in AD prevalence. Pedigree analysis and twin studies suggest that genetic components are part of the etiology, rather than only being risk factors for AD. The first autosomal dominant mutation in the amyloid precursor protein (APP) gene was described in 1991. Later, AD was also associated with mutated early-onset (presenilin 1/2, PSEN1/2 and APP) and late-onset (apolipoprotein E, ApoE) genes. Genome-wide association and linkage analysis studies with identified multiple genomic areas have implications for the treatment of AD. We conclude this review with future directions and clinical implications of genetic research in AD.
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Affiliation(s)
- Ahmed A Moustafa
- School of Social Sciences and Psychology, Western Sydney University, 48 Martin Pl, Sydney, New South Wales 2000, Australia
| | - Mubashir Hassan
- Department of Biology, College of Natural Sciences, Kongju National University, Gongju, Chungcheongnam 32588, Republic of Korea
| | - Doaa H Hewedi
- Psychogeriatric Research Center, Institute of Psychiatry, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Iman Hewedi
- Department of Pathology, Faculty of Medicine, Ain Shams University, Cairo 11566, Egypt
| | - Julia K Garami
- School of Social Sciences and Psychology, Western Sydney University, 48 Martin Pl, Sydney, New South Wales 2000, Australia
| | - Hany Al Ashwal
- College of Information Technology, Department of Computer Science and Software Eng-(CIT), United Arab Emirates University, Al-Ain 15551, United Arab Emirates
| | - Nazar Zaki
- College of Information Technology, Department of Computer Science and Software Eng-(CIT), United Arab Emirates University, Al-Ain 15551, United Arab Emirates
| | - Sung-Yum Seo
- Department of Biology, College of Natural Sciences, Kongju National University, Gongju, Chungcheongnam 32588, Republic of Korea
| | - Vassilis Cutsuridis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Nikolaou Plastira 100, GR-70013 Heraklion, Crete, Greece
| | - Sergio L Angulo
- Departments of Physiology/Pharmacology, The Robert F. Furchgott Center for Neural and Behavioral Science, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
| | - Joman Y Natesh
- Center for Molecular and Behavioural Neuroscience, Rutgers University, Newark, NJ 07102, USA
| | - Mohammad M Herzallah
- Center for Molecular and Behavioural Neuroscience, Rutgers University, Newark, NJ 07102, USA
| | - Dorota Frydecka
- Wroclaw Medical University, Department and Clinic of Psychiatry, 50-367 Wrocław, Poland
| | - Błażej Misiak
- Wroclaw Medical University, Department of Genetics, 50-368 Wroclaw, Poland
| | - Mohamed Salama
- School of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Wael Mohamed
- International Islamic University Malaysia, Jalan Gombak, Selangor 53100, Malaysia
| | - Mohamad El Haj
- University of Lille, CNRS, CHU Lille, UMR 9193 - SCALab - Sciences Cognitive Sciences Affectives, F-59000 Lille, France
| | - Michael Hornberger
- Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
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Cai B, Kasikara C, Doran AC, Ramakrishnan R, Birge RB, Tabas I. MerTK signaling in macrophages promotes the synthesis of inflammation resolution mediators by suppressing CaMKII activity. Sci Signal 2018; 11:eaar3721. [PMID: 30254055 PMCID: PMC6171110 DOI: 10.1126/scisignal.aar3721] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Inflammation resolution counterbalances excessive inflammation and restores tissue homeostasis after injury. Failure of resolution contributes to the pathology of numerous chronic inflammatory diseases. Resolution is mediated by endogenous specialized proresolving mediators (SPMs), which are derived from long-chain fatty acids by lipoxygenase (LOX) enzymes. 5-LOX plays a critical role in the biosynthesis of two classes of SPMs: lipoxins and resolvins. Cytoplasmic localization of the nonphosphorylated form of 5-LOX is essential for SPM biosynthesis, whereas nuclear localization of phosphorylated 5-LOX promotes proinflammatory leukotriene production. We previously showed that MerTK, an efferocytosis receptor on macrophages, promotes SPM biosynthesis by increasing the abundance of nonphosphorylated, cytoplasmic 5-LOX. We now show that activation of MerTK in human macrophages led to ERK-mediated expression of the gene encoding sarcoplasmic/endoplasmic reticulum calcium ATPase 2 (SERCA2), which decreased the cytosolic Ca2+ concentration and suppressed the activity of calcium/calmodulin-dependent protein kinase II (CaMKII). This, in turn, reduced the activities of the mitogen-activated protein kinase (MAPK) p38 and the kinase MK2, resulting in the increased abundance of the nonphosphorylated, cytoplasmic form of 5-LOX and enhanced SPM biosynthesis. In a zymosan-induced peritonitis model, an inflammatory setting in which macrophage MerTK activation promotes resolution, inhibition of ERK activation delayed resolution, which was characterized by an increased number of neutrophils and decreased amounts of SPMs in tissue exudates. These findings contribute to our understanding of how MerTK signaling induces 5-LOX-derived SPM biosynthesis and suggest a therapeutic strategy to boost inflammation resolution in settings where defective resolution promotes disease progression.
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Affiliation(s)
- Bishuang Cai
- Departments of Medicine, Pathology and Cell Biology, and Physiology, Columbia University, New York, NY 10032, USA.
| | - Canan Kasikara
- Departments of Medicine, Pathology and Cell Biology, and Physiology, Columbia University, New York, NY 10032, USA
| | - Amanda C Doran
- Departments of Medicine, Pathology and Cell Biology, and Physiology, Columbia University, New York, NY 10032, USA
| | | | - Raymond B Birge
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers University, New Jersey Medical School Cancer Center, Newark, NJ 07103, USA
| | - Ira Tabas
- Departments of Medicine, Pathology and Cell Biology, and Physiology, Columbia University, New York, NY 10032, USA.
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Newcombe EA, Camats-Perna J, Silva ML, Valmas N, Huat TJ, Medeiros R. Inflammation: the link between comorbidities, genetics, and Alzheimer's disease. J Neuroinflammation 2018; 15:276. [PMID: 30249283 PMCID: PMC6154824 DOI: 10.1186/s12974-018-1313-3] [Citation(s) in RCA: 320] [Impact Index Per Article: 53.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 09/11/2018] [Indexed: 12/21/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder, most cases of which lack a clear causative event. This has made the disease difficult to characterize and, thus, diagnose. Although some cases are genetically linked, there are many diseases and lifestyle factors that can lead to an increased risk of developing AD, including traumatic brain injury, diabetes, hypertension, obesity, and other metabolic syndromes, in addition to aging. Identifying common factors and trends between these conditions could enhance our understanding of AD and lead to the development of more effective treatments. Although the immune system is one of the body’s key defense mechanisms, chronic inflammation has been increasingly linked with several age-related diseases. Moreover, it is now well accepted that chronic inflammation has an important role in the onset and progression of AD. In this review, the different inflammatory signals associated with AD and its risk factors will be outlined to demonstrate how chronic inflammation may be influencing individual susceptibility to AD. Our goal is to bring attention to potential shared signals presented by the immune system during different conditions that could lead to the development of successful treatments.
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Affiliation(s)
- Estella A Newcombe
- Neurula Laboratory, Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Building 79, Brisbane, 4072, QLD, Australia.
| | - Judith Camats-Perna
- Neurula Laboratory, Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Building 79, Brisbane, 4072, QLD, Australia
| | - Mallone L Silva
- Neurula Laboratory, Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Building 79, Brisbane, 4072, QLD, Australia
| | - Nicholas Valmas
- Queensland Brain Institute, The University of Queensland, Brisbane, 4072, QLD, Australia
| | - Tee Jong Huat
- Neurula Laboratory, Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Building 79, Brisbane, 4072, QLD, Australia.,Centre for Stem Cell Ageing and Regenerative Engineering, The University of Queensland, Brisbane, 4072, QLD, Australia
| | - Rodrigo Medeiros
- Neurula Laboratory, Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Building 79, Brisbane, 4072, QLD, Australia.
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Tajbakhsh A, Rezaee M, Kovanen PT, Sahebkar A. Efferocytosis in atherosclerotic lesions: Malfunctioning regulatory pathways and control mechanisms. Pharmacol Ther 2018; 188:12-25. [DOI: 10.1016/j.pharmthera.2018.02.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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59
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Lan Y, Li Y, Li D, Li P, Wang J, Diao Y, Ye G, Li Y. Engulfment of platelets delays endothelial cell aging via girdin and its phosphorylation. Int J Mol Med 2018; 42:988-997. [PMID: 29786109 DOI: 10.3892/ijmm.2018.3685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 05/10/2018] [Indexed: 11/06/2022] Open
Abstract
Endothelial cells are critical in angiogenesis and maintain the homeostasis of the blood‑brain barrier (BBB). Platelets (PLTs) are essential in vascular biology, including angiogenesis. The present study aimed to investigate the effect of PLTs on the aging of endothelial cells. Human brain microvascular endothelial cells (HBMECs) and human astrocytes were co‑cultured to mimic the BBB. Transmission electron microscopy was used to observe the engulfment of PLTs. Confocal microscopy was used to observe the co‑localization of PLTs, girders of actin filament (girdin) and phosphorylated (p‑)girdin. Senescence‑associated β‑galactosidase (β‑gal) staining, 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide and flow cytometry were performed to examine the cell senescence, viability and apoptosis, respectively. Transwell assays were performed to examine cell invasion and migration. Western blot analysis was performed to detect the expression of girdin, AKT and p‑AKT. PLTs delayed senescence, and promoted the viability and resistance to apoptosis of the HBMECs. Cell invasion and migration were enhanced by PLTs. In addition, girdin and p‑girdin were essential to the engulfment of HBMECs to PLTs. Mechanically, the inhibition of AKT signals reversed the effect of PLTs on HBMECs by increasing the activity of β‑gal, decreasing the cell viability, and inhibiting the invasion and migration of the HBMECs. The engulfment of PLTs assisted in delaying the aging of endothelial cells via girdin and p‑girdin, in which the AKT signal was involved. The present study indicated a potential strategy for delaying endothelial cell aging in the treatment of central nervous system diseases.
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Affiliation(s)
- Yong Lan
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Yongjun Li
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Dajun Li
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Peng Li
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Jiyang Wang
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Yongpeng Diao
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Guodong Ye
- National Center of Gerontology, Department of Vascular Surgery, Beijing Hospital, Beijing 100730, P.R. China
| | - Yangfang Li
- Beijing Neurosurgical Institute, Capital Medical University, Beijing 100050, P.R. China
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60
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Moreno-Grau S, Hernández I, Heilmann-Heimbach S, Ruiz S, Rosende-Roca M, Mauleón A, Vargas L, Rodríguez-Gómez O, Alegret M, Espinosa A, Ortega G, Aguilera N, Abdelnour C, Neuroimaging Initiative AD, Gil S, Maier W, Sotolongo-Grau O, Tárraga L, Ramirez A, López-Arrrieta J, Antúnez C, Serrano-Ríos M, Boada M, Ruiz A. Genome-wide significant risk factors on chromosome 19 and the APOE locus. Oncotarget 2018; 9:24590-24600. [PMID: 29872490 PMCID: PMC5973862 DOI: 10.18632/oncotarget.25083] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 03/22/2018] [Indexed: 12/30/2022] Open
Abstract
The apolipoprotein E (APOE) gene on chromosome 19q13.32, was the first, and remains the strongest, genetic risk factor for Alzheimer’s disease (AD). Additional signals associated with AD have been located in chromosome 19, including ABCA7 (19p13.3) and CD33 (19q13.41). The ABCA7 gene has been replicated in most populations. However, the contribution to AD of other signals close to APOE gene remains controversial. Possible explanations for inconsistency between reports include long range linkage disequilibrium (LRLD). We analysed the contribution of ABCA7 and CD33 loci to AD risk and explore LRLD patterns across APOE region. To evaluate AD risk conferred by ABCA7 rs4147929:G>A and CD33 rs3865444:C>A, we used a large Spanish population (1796 AD cases, 2642 controls). The ABCA7 rs4147929:G>A SNP effect was nominally replicated in the Spanish cohort and reached genome-wide significance after meta-analysis (odds ratio (OR)=1.15, 95% confidence interval (95% CI)=1.12–1.19; P = 1.60 x 10-19). CD33 rs3865444:C>A was not associated with AD in the dataset. The meta-analysis was also negative (OR=0.98, 95% CI=0.93–1.04; P=0.48). After exploring LRLD patterns between APOE and CD33 in several datasets, we found significant LD (D’ >0.20; P <0.030) between APOE-Ɛ2 and CD33 rs3865444C>A in two of five datasets, suggesting the presence of a non-universal long range interaction between these loci affecting to some populations. In conclusion, we provide here evidence of genetic association of the ABCA7 locus in the Spanish population and also propose a plausible explanation for the controversy on the contribution of CD33 to AD susceptibility.
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Affiliation(s)
- Sonia Moreno-Grau
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Isabel Hernández
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Stefanie Heilmann-Heimbach
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life & Brain Center, University of Bonn, Bonn, Germany
| | - Susana Ruiz
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Maitée Rosende-Roca
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Ana Mauleón
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Liliana Vargas
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Octavio Rodríguez-Gómez
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Montserrat Alegret
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Ana Espinosa
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Gemma Ortega
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Nuria Aguilera
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Carla Abdelnour
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Alzheimer's Disease Neuroimaging Initiative
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain.,Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life & Brain Center, University of Bonn, Bonn, Germany.,Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany.,German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany.,Department of Psychiatry and Psychotherapy, University of Cologne, Cologne, Germany.,Memory Unit, University Hospital La Paz-Cantoblanco, Madrid, Spain.,Dementia Unit, University Hospital Virgen de la Arrixaca, Murcia, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Spain, Hospital Clínico San Carlos, Madrid, Spain
| | - Silvia Gil
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Wolfgang Maier
- Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany.,German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany
| | - Oscar Sotolongo-Grau
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Lluís Tárraga
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Alfredo Ramirez
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany.,Department of Psychiatry and Psychotherapy, University of Cologne, Cologne, Germany
| | | | - Carmen Antúnez
- Dementia Unit, University Hospital Virgen de la Arrixaca, Murcia, Spain
| | - Manuel Serrano-Ríos
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Spain, Hospital Clínico San Carlos, Madrid, Spain
| | - Mercè Boada
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
| | - Agustín Ruiz
- Research Center and Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, Univesitat Internacional de Catalunya, Barcelona, Spain
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61
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Vasquez JB, Simpson JF, Harpole R, Estus S. Alzheimer's Disease Genetics and ABCA7 Splicing. J Alzheimers Dis 2018; 59:633-641. [PMID: 28655137 DOI: 10.3233/jad-170872] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Both common and rare polymorphisms within ABCA7 have been associated with Alzheimer's disease (AD). In particular, the rare AD associated polymorphism rs200538373 was associated with altered ABCA7 exon 41 splicing and an AD risk odds ratio of ∼1.9. To probe the role of this polymorphism in ABCA7 splicing, we used minigene studies and qPCR of human brain RNA. We report aberrant ABCA7 exon 41 splicing in the brain of a carrier of the rs200538373 minor C allele. Moreover, minigene studies show that rs200538373 acts as a robust functional variant in vitro. Lastly, although the ABCA7 isoform with an extended exon 41 is predicted to undergo nonsense mediated RNA decay, this was not supported by qPCR analyses, which showed relatively normal ABCA7 mRNA levels in the carrier of the rs200538373 minor C allele. In summary, rs200538373 is a functional polymorphism that alters ABCA7 exon 41 splicing without grossly altering the level of ABCA7 mRNA.
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Affiliation(s)
- Jared B Vasquez
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - James F Simpson
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Ryan Harpole
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Steven Estus
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
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62
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Yamazaki K, Yoshino Y, Mori T, Yoshida T, Ozaki Y, Sao T, Mori Y, Ochi S, Iga JI, Ueno SI. Gene Expression and Methylation Analysis of ABCA7 in Patients with Alzheimer's Disease. J Alzheimers Dis 2018; 57:171-181. [PMID: 28222527 DOI: 10.3233/jad-161195] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND/OBJECTIVE The aim of this study was to examine the blood gene expression and methylation of ATP-binding cassette sub-family A member 7 gene (ABCA7) as a biological marker of AD. METHODS AD subjects (n = 50; 11 males, 77.7±6.05 years old) and age- and sex-matched healthy controls (n = 50) were recruited. A single nucleotide polymorphism in ABCA7 (rs3764650), methylation rates of CpG sites in the ABCA7 promoter region, and ABCA7 mRNA expression levels in peripheral blood were examined. RESULTS The distribution of the rs3764650 polymorphism in AD subjects was not different from that of controls. Although the methylation rates of AD subjects were not significantly different from those of controls, the ABCA7 mRNA expression level in AD subjects was significantly higher than that in controls. Additionally, the ABCA7 mRNA expression level in AD subjects was significantly correlated with Mini-Mental State Examination recall, the Alzheimer's Disease Assessment Scale total score, and the Clinical Dementia Rating score. We also found a significant correlation between the ABCA7 mRNA expression level and duration of illness. CONCLUSION The ABCA7 mRNA expression level in peripheral blood may be a marker for early stages of AD and disease progression regardless of rs3764650 and the methylation rate of its promoter.
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63
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Pimenova AA, Raj T, Goate AM. Untangling Genetic Risk for Alzheimer's Disease. Biol Psychiatry 2018; 83:300-310. [PMID: 28666525 PMCID: PMC5699970 DOI: 10.1016/j.biopsych.2017.05.014] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 05/15/2017] [Accepted: 05/15/2017] [Indexed: 01/01/2023]
Abstract
Alzheimer's disease (AD) is a genetically heterogeneous neurodegenerative disorder caused by fully penetrant single gene mutations in a minority of cases, while the majority of cases are sporadic or show modest familial clustering. These cases are of late onset and likely result from the interaction of many genes and the environment. More than 30 loci have been implicated in AD by a combination of linkage, genome-wide association, and whole genome/exome sequencing. We have learned from these studies that perturbations in endolysosomal, lipid metabolism, and immune response pathways substantially contribute to sporadic AD pathogenesis. We review here current knowledge about functions of AD susceptibility genes, highlighting cells of the myeloid lineage as drivers of at least part of the genetic component in late-onset AD. Although targeted resequencing utilized for the identification of causal variants has discovered coding mutations in some AD-associated genes, a lot of risk variants lie in noncoding regions. Here we discuss the use of functional genomics approaches that integrate transcriptomic, epigenetic, and endophenotype traits with systems biology to annotate genetic variants, and to facilitate discovery of AD risk genes. Further validation in cell culture and mouse models will be necessary to establish causality for these genes. This knowledge will allow mechanism-based design of novel therapeutic interventions in AD and promises coherent implementation of treatment in a personalized manner.
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Affiliation(s)
- Anna A Pimenova
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York; Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Towfique Raj
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York; Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Alison M Goate
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York; Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, New York.
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64
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Aikawa T, Holm ML, Kanekiyo T. ABCA7 and Pathogenic Pathways of Alzheimer's Disease. Brain Sci 2018; 8:E27. [PMID: 29401741 PMCID: PMC5836046 DOI: 10.3390/brainsci8020027] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 02/01/2018] [Accepted: 02/03/2018] [Indexed: 12/22/2022] Open
Abstract
The ATP-binding cassette (ABC) reporter family functions to regulate the homeostasis of phospholipids and cholesterol in the central nervous system, as well as peripheral tissues. ABCA7 belongs to the A subfamily of ABC transporters, which shares 54% sequence identity with ABCA1. While ABCA7 is expressed in a variety of tissues/organs, including the brain, recent genome-wide association studies (GWAS) have identified ABCA7 gene variants as susceptibility loci for late-onset Alzheimer's disease (AD). More important, subsequent genome sequencing analyses have revealed that premature termination codon mutations in ABCA7 are associated with the increased risk for AD. Alzheimer's disease is a progressive neurodegenerative disease and the most common cause of dementia, where the accumulation and deposition of amyloid-β (Aβ) peptides cleaved from amyloid precursor protein (APP) in the brain trigger the pathogenic cascade of the disease. In consistence with human genetic studies, increasing evidence has demonstrated that ABCA7 deficiency exacerbates Aβ pathology using in vitro and in vivo models. While ABCA7 has been shown to mediate phagocytic activity in macrophages, ABCA7 is also involved in the microglial Aβ clearance pathway. Furthermore, ABCA7 deficiency results in accelerated Aβ production, likely by facilitating endocytosis and/or processing of APP. Taken together, current evidence suggests that ABCA7 loss-of-function contributes to AD-related phenotypes through multiple pathways. A better understanding of the function of ABCA7 beyond lipid metabolism in both physiological and pathological conditions becomes increasingly important to explore AD pathogenesis.
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Affiliation(s)
- Tomonori Aikawa
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA.
| | - Marie-Louise Holm
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA.
| | - Takahisa Kanekiyo
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA.
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65
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Bamji-Mirza M, Li Y, Najem D, Liu QY, Walker D, Lue LF, Stupak J, Chan K, Li J, Ghani M, Yang Z, Rogaeva E, Zhang W. Genetic Variations in ABCA7 Can Increase Secreted Levels of Amyloid-β40 and Amyloid-β42 Peptides and ABCA7 Transcription in Cell Culture Models. J Alzheimers Dis 2018; 53:875-92. [PMID: 27314524 DOI: 10.3233/jad-150965] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Alzheimer's disease (AD) is characterized by extracellular deposits of amyloid-β (Aβ) in the brain. ABCA7 is highly expressed in the brain and a susceptibility gene for late-onset AD (LOAD). The minor alleles at two ABCA7 single-nucleotide polymorphisms (SNPs), rs3764650 (T>G; intron13) and rs3752246 at a predicted myristoylation site (C>G; exon33; p.Gly1527Ala), are significantly associated with LOAD risk; however, the mechanism of this association is unknown. Functional consequences of both SNPs were examined in HEK293 and CHO cells stably expressing AβPPSwe. Luciferase reporter assays in HEK293 cells suggested that intron13 carrying rs3764650 major T-allele (int13-T) possessed promoter-enhancing capabilities. Co-transfection experiments with hABCA7 and int13-T resulted in significantly increased ABCA7 protein level relative to that with int13-G. Expression of hABCA7 carrying rs3752246 risk allele led to increases in secreted Aβ40 and Aβ42 and β-secretase activity in CHO- and HEK-AβPPSwe cells. Hydroxymyristic acid treatment of cells expressing hABCA7 carrying the rs3752246 major G allele resulted in increased β-secretase activity and levels of Aβ, suggesting that lack of myristoylation contributes to the observed cell-phenotypes. Molecular weight determination, by gel-electrophoresis and mass spectrometry, of hABCA7 peptides spanning position 1527 showed loss of post-translational modification in the risk-allele peptide. These results suggest that decreased expression, or impaired function, of ABCA7 may contribute to AD pathology.
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Affiliation(s)
- Michelle Bamji-Mirza
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | - Yan Li
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | - Dema Najem
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | - Qing Yan Liu
- Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | | | - Lih-Fen Lue
- Banner Sun Health Research Institute, Sun City, AZ, USA
| | - Jacek Stupak
- Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | - Kenneth Chan
- Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | - Jianjun Li
- Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
| | - Mahdi Ghani
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Ze Yang
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Chinese Ministry of Health, Beijing, China
| | - Ekaterina Rogaeva
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Wandong Zhang
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Human Health Therapeutics Portfolio, Life Sciences Division, National Research Council Canada, Ottawa, ON, Canada
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66
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Fu Y, Hsiao JHT, Paxinos G, Halliday GM, Kim WS. ABCA7 Mediates Phagocytic Clearance of Amyloid-β in the Brain. J Alzheimers Dis 2018; 54:569-84. [PMID: 27472885 DOI: 10.3233/jad-160456] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by dementia and abnormal deposits of aggregated amyloid-β in the brain. Recent genome-wide association studies have revealed that ABCA7 is strongly associated with AD. In vitro evidence suggests that the role of ABCA7 is related to phagocytic activity. Deletion of ABCA7 in a mouse model of AD exacerbates cerebral amyloid-β plaque load. However, the biological role of ABCA7 in AD brain pathogenesis is unknown. We show that ABCA7 is highly expressed in microglia and when monocytes are differentiated into macrophages. We hypothesized that ABCA7 plays a protective role in the brain that is related to phagocytic clearance of amyloid-β. We isolated microglia and macrophages from Abca7-/- and wild type mice and tested them for their capacity to phagocytose amyloid-β oligomers. We found that the phagocytic clearance of amyloid-β was substantially reduced in both microglia and macrophages from Abca7-/- mice compared to wild type mice. Consistent with these results, in vivo phagocytic clearance of amyloid-β oligomers in the hippocampus was reduced in Abca7-/- mice. Furthermore, ABCA7 transcription was upregulated in AD brains and in amyloidogenic mouse brains specifically in the hippocampus as a response to the amyloid-β pathogenic state. Together these results indicate that ABCA7 mediates phagocytic clearance of amyloid-β in the brain, and reveal a mechanism by which loss of function of ABCA7 increases the susceptibility to AD.
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Affiliation(s)
- YuHong Fu
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Jen-Hsiang T Hsiao
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - George Paxinos
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Glenda M Halliday
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Woojin Scott Kim
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
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Yamauchi Y, Rogers MA. Sterol Metabolism and Transport in Atherosclerosis and Cancer. Front Endocrinol (Lausanne) 2018; 9:509. [PMID: 30283400 PMCID: PMC6157400 DOI: 10.3389/fendo.2018.00509] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 08/14/2018] [Indexed: 01/22/2023] Open
Abstract
Cholesterol is a vital lipid molecule for mammalian cells, regulating fluidity of biological membranes, and serving as an essential constituent of lipid rafts. Mammalian cells acquire cholesterol from extracellular lipoproteins and from de novo synthesis. Cholesterol biosynthesis generates various precursor sterols. Cholesterol undergoes metabolic conversion into oxygenated sterols (oxysterols), bile acids, and steroid hormones. Cholesterol intermediates and metabolites have diverse and important cellular functions. A network of molecular machineries including transcription factors, protein modifiers, sterol transporters/carriers, and sterol sensors regulate sterol homeostasis in mammalian cells and tissues. Dysfunction in metabolism and transport of cholesterol, sterol intermediates, and oxysterols occurs in various pathophysiological settings such as atherosclerosis, cancers, and neurodegenerative diseases. Here we review the cholesterol, intermediate sterol, and oxysterol regulatory mechanisms and intracellular transport machineries, and discuss the roles of sterols and sterol metabolism in human diseases.
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Affiliation(s)
- Yoshio Yamauchi
- Nutri-Life Science Laboratory, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
- AMED-CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
- *Correspondence: Yoshio Yamauchi
| | - Maximillian A. Rogers
- Division of Cardiovascular Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
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68
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Kjeldsen EW, Tybjærg-Hansen A, Nordestgaard BG, Frikke-Schmidt R. ABCA7 and risk of dementia and vascular disease in the Danish population. Ann Clin Transl Neurol 2017; 5:41-51. [PMID: 29376091 PMCID: PMC5771325 DOI: 10.1002/acn3.506] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 10/26/2017] [Indexed: 01/02/2023] Open
Abstract
Objective ATP‐binding‐cassette transporter A7(ABCA7) is suggested to be involved in lipid transport as well as in phagocytosis of amyloid‐β in the brain. We tested the hypothesis that a common genetic variant in ABCA7 is associated with dementia, ischemic heart disease, ischemic cerebrovascular disease, and with lipid levels in the general population, independent of the common apolipoprotein E(APOE) genotype. Methods For this purpose, we genotyped a common genetic variant in ABCA7, identified in genome‐wide‐association‐studies of Alzheimer's disease, in 104,258 individuals from the Danish general population, and also meta‐analyzed our results with publicly available consortia data. Results Multifactorially adjusted hazard ratios for Alzheimer's disease were 1.07 (95% confidence interval:0.93–1.23) and 1.72 (1.24–2.40) for GA and AA versus GG genotype. Results were similar after APOE genotype adjustment and when only APOE ɛ33 carriers were studied. Including 178,304 individuals, the meta‐analyzed odds ratio for Alzheimer's disease per one allele ABCA7 rs4147929 increase was 1.15 (1.12–1.18). ABCA7 genotype was not convincingly associated with vascular dementia, ischemic heart disease, ischemic cerebrovascular disease, or with lipid levels. Including 288,563 individuals, meta‐analyzed odds ratios for ischemic heart disease per one allele ABCA7 rs4147929 increase was 1.01 (0.99–1.03). Interpretation A common genetic variant in ABCA7 was associated with high risk of Alzheimer's disease independent of APOE genotype. The lack of association with vascular dementia, ischemic heart disease, ischemic cerebrovascular disease, and with lipid levels suggests that ABCA7 is not important for atherosclerosis. Thus, our findings support the suggested role of ABCA7 in Alzheimer's disease pathology and phagocytic clearance of amyloid‐β in the brain.
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Affiliation(s)
- Emilie W Kjeldsen
- Department of Clinical Biochemistry Rigshospitalet Copenhagen Denmark
| | - Anne Tybjærg-Hansen
- Department of Clinical Biochemistry Rigshospitalet Copenhagen Denmark.,Department of Clinical Medicine Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark.,The Copenhagen General Population Study Herlev and Gentofte Hospital Herlev Denmark.,The Copenhagen City Heart Study Frederiksberg Hospital Frederiksberg Denmark
| | - Børge G Nordestgaard
- Department of Clinical Medicine Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark.,The Copenhagen General Population Study Herlev and Gentofte Hospital Herlev Denmark.,The Copenhagen City Heart Study Frederiksberg Hospital Frederiksberg Denmark.,Department of Clinical Biochemistry Herlev and Gentofte Hospital Herlev Denmark
| | - Ruth Frikke-Schmidt
- Department of Clinical Biochemistry Rigshospitalet Copenhagen Denmark.,Department of Clinical Medicine Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark.,The Copenhagen General Population Study Herlev and Gentofte Hospital Herlev Denmark
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69
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Bhatia S, Fu Y, Hsiao JHT, Halliday GM, Kim WS. Deletion of Alzheimer's Disease Risk Gene ABCA7 Alters White Adipose Tissue Development and Leptin Levels. J Alzheimers Dis Rep 2017; 1:237-247. [PMID: 30480241 PMCID: PMC6159609 DOI: 10.3233/adr-170029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
ATP-binding cassette A7 (ABCA7) is a genetic risk factor for late-onset Alzheimer’s disease (AD). It belongs to a group of transporter genes that specializes in regulating lipid transport in the periphery as well as in the brain. ABCA7 has been implicated in a number of roles relating to AD pathology, including phagocytic clearance of amyloid-β peptides. We have discovered that deletion of ABCA7 in mouse causes a dramatic reduction in white adipose tissue (WAT) in female mice. WAT is important in AD context because it is the primary producer of leptin, which is a hormone that is known to modulate AD neuropathology. WAT in male Abca7–/– mice was not altered. The pathological link between ABCA7 and WAT that impacts on AD is unknown. Our transcription analysis revealed that lipin-1 expression was significantly upregulated in female Abca7–/– mice, indicating that ABCA7 affects WAT development. The circulating leptin level was significantly reduced in female Abca7–/– mice without any change in WAT leptin mRNA or protein expression, indicating that ABCA7 does not affect leptin production, but alters the circulating leptin level indirectly by affecting WAT development. Insulin is a key hormone that regulates WAT development, i.e., adipogenesis, and it was significantly reduced in female Abca7–/– mice. These data when put together suggest that ABCA7 plays a role in regulating WAT development and consequently circulating leptin levels, which are known to modulate AD neuropathology.
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Affiliation(s)
- Surabhi Bhatia
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Camperdown, NSW, Australia
| | - YuHong Fu
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Camperdown, NSW, Australia
| | - Jen-Hsiang T Hsiao
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Camperdown, NSW, Australia.,School of Medical Sciences, University of New South Wales and Neuroscience Research Australia, Randwick, NSW, Australia
| | - Glenda M Halliday
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Camperdown, NSW, Australia.,School of Medical Sciences, University of New South Wales and Neuroscience Research Australia, Randwick, NSW, Australia
| | - Woojin Scott Kim
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Camperdown, NSW, Australia.,School of Medical Sciences, University of New South Wales and Neuroscience Research Australia, Randwick, NSW, Australia
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70
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Tang M, Reitz C. Genetics of Alzheimer's disease: an update. FUTURE NEUROLOGY 2017. [DOI: 10.2217/fnl-2017-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It is clear that late-onset Alzheimer's disease (AD), the most common form of dementia in western societies, has a significant genetic component. The recent technological advances in high-throughput genome technologies have enabled the identification of more than 20 novel susceptibility loci. These findings have significantly advanced the understanding of the molecular mechanisms potentially underlying AD etiology, and have therefore provided valuable information for the development of targets for genetic testing, prevention and treatment. This article reviews these recent findings in AD genomics and discusses their implications for understanding the molecular underpinnings of the disease.
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Affiliation(s)
- Min Tang
- The Gertrude H Sergievsky Center, Columbia University, 630 West 168th Street, NY 10032, USA
| | - Christiane Reitz
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, 630 West 168th Street, NY 10032, USA
- The Gertrude H Sergievsky Center, Columbia University, 630 West 168th Street, NY 10032, USA
- The Department of Neurology, Columbia University, NY 10032, USA
- The Department of Epidemiology, Columbia University, NY 10032, USA
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71
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Hansen DV, Hanson JE, Sheng M. Microglia in Alzheimer's disease. J Cell Biol 2017; 217:459-472. [PMID: 29196460 PMCID: PMC5800817 DOI: 10.1083/jcb.201709069] [Citation(s) in RCA: 1076] [Impact Index Per Article: 153.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/05/2017] [Accepted: 11/14/2017] [Indexed: 12/15/2022] Open
Abstract
Hansen et al. review the potential dual helpful and harmful roles of microglia in the development and progression of Alzheimer’s disease. Proliferation and activation of microglia in the brain, concentrated around amyloid plaques, is a prominent feature of Alzheimer’s disease (AD). Human genetics data point to a key role for microglia in the pathogenesis of AD. The majority of risk genes for AD are highly expressed (and many are selectively expressed) by microglia in the brain. There is mounting evidence that microglia protect against the incidence of AD, as impaired microglial activities and altered microglial responses to β-amyloid are associated with increased AD risk. On the other hand, there is also abundant evidence that activated microglia can be harmful to neurons. Microglia can mediate synapse loss by engulfment of synapses, likely via a complement-dependent mechanism; they can also exacerbate tau pathology and secrete inflammatory factors that can injure neurons directly or via activation of neurotoxic astrocytes. Gene expression profiles indicate multiple states of microglial activation in neurodegenerative disease settings, which might explain the disparate roles of microglia in the development and progression of AD pathology.
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Affiliation(s)
- David V Hansen
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA
| | - Jesse E Hanson
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA
| | - Morgan Sheng
- Department of Neuroscience, Genentech, Inc., South San Francisco, CA
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72
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Trafficking in Alzheimer's Disease: Modulation of APP Transport and Processing by the Transmembrane Proteins LRP1, SorLA, SorCS1c, Sortilin, and Calsyntenin. Mol Neurobiol 2017; 55:5809-5829. [PMID: 29079999 DOI: 10.1007/s12035-017-0806-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/17/2017] [Indexed: 12/11/2022]
Abstract
The amyloid precursor protein (APP), one key player in Alzheimer's disease (AD), is extensively processed by different proteases. This leads to the generation of diverging fragments including the amyloid β (Aβ) peptide, which accumulates in brains of AD patients. Subcellular trafficking of APP is an important aspect for its proteolytic conversion, since the various secretases which cleave APP are located in different cellular compartments. As a consequence, altered subcellular targeting of APP is thought to directly affect the degree to which Aβ is generated. The mechanisms underlying intracellular APP transport are critical to understand AD pathogenesis and can serve as a target for future pharmacological interventions. In the recent years, a number of APP interacting proteins were identified which are implicated in sorting of APP, thereby influencing APP processing at different angles of the secretory or endocytic pathway. This review provides an update on the proteolytic processing of APP and the interplay of the transmembrane proteins low-density lipoprotein receptor-related protein 1, sortilin-receptor with A-type repeats, SorCS1c, sortilin, and calsyntenin. We discuss the specific interactions with APP, the capacity to modulate the intracellular itinerary and the proteolytic conversion of APP, a possible involvement in the clearance of Aβ, and the implications of these transmembrane proteins in AD and other neurodegenerative diseases.
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73
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De Roeck A, Van den Bossche T, van der Zee J, Verheijen J, De Coster W, Van Dongen J, Dillen L, Baradaran-Heravi Y, Heeman B, Sanchez-Valle R, Lladó A, Nacmias B, Sorbi S, Gelpi E, Grau-Rivera O, Gómez-Tortosa E, Pastor P, Ortega-Cubero S, Pastor MA, Graff C, Thonberg H, Benussi L, Ghidoni R, Binetti G, de Mendonça A, Martins M, Borroni B, Padovani A, Almeida MR, Santana I, Diehl-Schmid J, Alexopoulos P, Clarimon J, Lleó A, Fortea J, Tsolaki M, Koutroumani M, Matěj R, Rohan Z, De Deyn P, Engelborghs S, Cras P, Van Broeckhoven C, Sleegers K. Deleterious ABCA7 mutations and transcript rescue mechanisms in early onset Alzheimer's disease. Acta Neuropathol 2017; 134:475-487. [PMID: 28447221 PMCID: PMC5563332 DOI: 10.1007/s00401-017-1714-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/18/2017] [Accepted: 04/19/2017] [Indexed: 12/12/2022]
Abstract
Premature termination codon (PTC) mutations in the ATP-Binding Cassette, Sub-Family A, Member 7 gene (ABCA7) have recently been identified as intermediate-to-high penetrant risk factor for late-onset Alzheimer’s disease (LOAD). High variability, however, is observed in downstream ABCA7 mRNA and protein expression, disease penetrance, and onset age, indicative of unknown modifying factors. Here, we investigated the prevalence and disease penetrance of ABCA7 PTC mutations in a large early onset AD (EOAD)—control cohort, and examined the effect on transcript level with comprehensive third-generation long-read sequencing. We characterized the ABCA7 coding sequence with next-generation sequencing in 928 EOAD patients and 980 matched control individuals. With MetaSKAT rare variant association analysis, we observed a fivefold enrichment (p = 0.0004) of PTC mutations in EOAD patients (3%) versus controls (0.6%). Ten novel PTC mutations were only observed in patients, and PTC mutation carriers in general had an increased familial AD load. In addition, we observed nominal risk reducing trends for three common coding variants. Seven PTC mutations were further analyzed using targeted long-read cDNA sequencing on an Oxford Nanopore MinION platform. PTC-containing transcripts for each investigated PTC mutation were observed at varying proportion (5–41% of the total read count), implying incomplete nonsense-mediated mRNA decay (NMD). Furthermore, we distinguished and phased several previously unknown alternative splicing events (up to 30% of transcripts). In conjunction with PTC mutations, several of these novel ABCA7 isoforms have the potential to rescue deleterious PTC effects. In conclusion, ABCA7 PTC mutations play a substantial role in EOAD, warranting genetic screening of ABCA7 in genetically unexplained patients. Long-read cDNA sequencing revealed both varying degrees of NMD and transcript-modifying events, which may influence ABCA7 dosage, disease severity, and may create opportunities for therapeutic interventions in AD.
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74
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Rahman MR, Tajmim A, Ali M, Sharif M. Overview and Current Status of Alzheimer's Disease in Bangladesh. J Alzheimers Dis Rep 2017; 1:27-42. [PMID: 30480227 PMCID: PMC6159651 DOI: 10.3233/adr-170012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Alzheimer’s disease (AD) is a complex neurological disorder with economic, social, and medical burdens which is acknowledged as leading cause of dementia marked by the accumulation and aggregation of amyloid-β peptide and phosphorylated tau (p-tau) protein and concomitant dementia, neuron loss and brain atrophy. AD is the most prevalent neurodegenerative brain disorder with sporadic etiology, except for a small fraction of cases with familial inheritance where familial forms of AD are correlated to mutations in three functionally related genes: the amyloid-β protein precursor and presenilins 1 and 2, two key γ-secretase components. The common clinical features of AD are memory impairment that interrupts daily life, difficulty in accomplishing usual tasks, confusion with time or place, trouble understanding visual images and spatial relationships. Age is the most significant risk factor for AD, whereas other risk factors correlated with AD are hypercholesterolemia, hypertension, atherosclerosis, coronary heart disease, smoking, obesity, and diabetes. Despite decades of research, there is no satisfying therapy which will terminate the advancement of AD by acting on the origin of the disease process, whereas currently available therapeutics only provide symptomatic relief but fail to attain a definite cure and prevention. This review also represents the current status of AD in Bangladesh.
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Affiliation(s)
- Md Rashidur Rahman
- Department of Pharmacy, Jessore University of Science and Technology, Jessore, Bangladesh
| | - Afsana Tajmim
- Department of Pharmacy, Jessore University of Science and Technology, Jessore, Bangladesh
| | - Mohammad Ali
- Department of Pharmacy, Jessore University of Science and Technology, Jessore, Bangladesh
| | - Mostakim Sharif
- Department of Pharmacy, Jessore University of Science and Technology, Jessore, Bangladesh
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75
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Morizawa YM, Hirayama Y, Ohno N, Shibata S, Shigetomi E, Sui Y, Nabekura J, Sato K, Okajima F, Takebayashi H, Okano H, Koizumi S. Reactive astrocytes function as phagocytes after brain ischemia via ABCA1-mediated pathway. Nat Commun 2017. [PMID: 28642575 PMCID: PMC5481424 DOI: 10.1038/s41467-017-00037-1] [Citation(s) in RCA: 242] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Astrocytes become reactive following various brain insults; however, the functions of reactive astrocytes are poorly understood. Here, we show that reactive astrocytes function as phagocytes after transient ischemic injury and appear in a limited spatiotemporal pattern. Following transient brain ischemia, phagocytic astrocytes are observed within the ischemic penumbra region during the later stage of ischemia. However, phagocytic microglia are mainly observed within the ischemic core region during the earlier stage of ischemia. Phagocytic astrocytes upregulate ABCA1 and its pathway molecules, MEGF10 and GULP1, which are required for phagocytosis, and upregulation of ABCA1 alone is sufficient for enhancement of phagocytosis in vitro. Disrupting ABCA1 in reactive astrocytes result in fewer phagocytic inclusions after ischemia. Together, these findings suggest that astrocytes are transformed into a phagocytic phenotype as a result of increase in ABCA1 and its pathway molecules and contribute to remodeling of damaged tissues and penumbra networks. Astrocytic phagocytosis has been shown to play a role in synaptic pruning during development, but whether adult astrocytes possess phagocytic ability is unclear. Here the authors show that following brain ischemia, reactive astrocytes become phagocytic and engulf debris via the ABCA1 pathway.
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Affiliation(s)
- Yosuke M Morizawa
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, 409-3898, Japan.,Department of Super-network Brain Physiology, Graduate School of Life Science, Tohoku University, Sendai, Miyagi, 980-8575, Japan
| | - Yuri Hirayama
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, 409-3898, Japan
| | - Nobuhiko Ohno
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Shinsuke Shibata
- Department of Physiology and Electron Microscope Laboratory, Keio University School of Medicine, Shinjuku, Tokyo, 160-8582, Japan
| | - Eiji Shigetomi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, 409-3898, Japan
| | - Yang Sui
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan.,Department of Physiological Sciences, The Graduate School for Advanced Study, Hayama, Kanagawa, 240-0193, Japan
| | - Koichi Sato
- Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, 371-8512, Japan
| | - Fumikazu Okajima
- Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, 371-8512, Japan
| | - Hirohide Takebayashi
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata, 951-8510, Japan
| | - Hideyuki Okano
- Department of Physiology and Electron Microscope Laboratory, Keio University School of Medicine, Shinjuku, Tokyo, 160-8582, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, 409-3898, Japan.
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76
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Engulfment signals and the phagocytic machinery for apoptotic cell clearance. Exp Mol Med 2017; 49:e331. [PMID: 28496201 PMCID: PMC5454446 DOI: 10.1038/emm.2017.52] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 12/15/2016] [Indexed: 02/07/2023] Open
Abstract
The clearance of apoptotic cells is an essential process for tissue homeostasis. To this end, cells undergoing apoptosis must display engulfment signals, such as ‘find-me' and ‘eat-me' signals. Engulfment signals are recognized by multiple types of phagocytic machinery in phagocytes, leading to prompt clearance of apoptotic cells. In addition, apoptotic cells and phagocytes release tolerogenic signals to reduce immune responses against apoptotic cell-derived self-antigens. Here we discuss recent advances in our knowledge of engulfment signals, the phagocytic machinery and the signal transduction pathways for apoptotic cell engulfment.
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77
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ATP Binding Cassette Transporter ABCA7 Regulates NKT Cell Development and Function by Controlling CD1d Expression and Lipid Raft Content. Sci Rep 2017; 7:40273. [PMID: 28091533 PMCID: PMC5238393 DOI: 10.1038/srep40273] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 11/28/2016] [Indexed: 12/16/2022] Open
Abstract
ABCA7 is an ABC transporter expressed on the plasma membrane, and actively exports phospholipid complexes from the cytoplasmic to the exocytoplasmic leaflet of membranes. Invariant NKT (iNKT) cells are a subpopulation of T lymphocytes that recognize glycolipid antigens in the context of CD1d-mediated antigen presentation. In this study, we demonstrate that ABCA7 regulates the development of NKT cells in a cell-extrinsic manner. We found that in Abca7−/− mice there is reduced expression of CD1d accompanied by an alteration in lipid raft content on the plasma membrane of thymocytes and antigen presenting cells. Together, these alterations caused by absence of ABCA7 negatively affect NKT cell development and function.
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78
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Allen M, Lincoln SJ, Corda M, Watzlawik JO, Carrasquillo MM, Reddy JS, Burgess JD, Nguyen T, Malphrus K, Petersen RC, Graff-Radford NR, Dickson DW, Ertekin-Taner N. ABCA7 loss-of-function variants, expression, and neurologic disease risk. NEUROLOGY-GENETICS 2017; 3:e126. [PMID: 28097223 PMCID: PMC5217615 DOI: 10.1212/nxg.0000000000000126] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 11/21/2016] [Indexed: 11/17/2022]
Abstract
Objective: To investigate and characterize putative “loss-of-function” (LOF) adenosine triphosphate–binding cassette, subfamily A member 7 (ABCA7) mutations reported to associate with Alzheimer disease (AD) risk. Methods: We genotyped 6 previously reported ABCA7 putative LOF variants in 1,465 participants with AD, 381 participants with other neuropathologies (non-AD), and 1,043 controls and assessed the overall mutational burden for association with different diagnosis groups. We measured brain ABCA7 protein and messenger RNA (mRNA) levels using Western blot and quantitative PCR, respectively, in 11 carriers of the 3 most common variants, and sequenced all 47 ABCA7 exons in these participants to screen for other coding variants. Results: At least one of the investigated variants was identified in 45 participants with late-onset Alzheimer disease, 12 participants with other neuropathologies, and 11 elderly controls. Association analysis revealed a significantly higher burden of these variants in participants with AD (p = 5.00E-04) and those with other neuropathologies (p = 8.60E-03) when compared with controls. Concurrent analysis of brain ABCA7 mRNA and protein revealed lower protein but not mRNA in p.L1403fs carriers, lower mRNA but not protein in p.E709fs carriers, and additional deleterious mutations in some c.5570+5G>C carriers. Conclusions: Our results suggest that LOF may not be a common mechanism for these ABCA7 variants and expand the list of neurologic diseases enriched for them.
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Affiliation(s)
- Mariet Allen
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Sarah J Lincoln
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Morgane Corda
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Jens O Watzlawik
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Minerva M Carrasquillo
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Joseph S Reddy
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Jeremy D Burgess
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Thuy Nguyen
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Kimberly Malphrus
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Ronald C Petersen
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Neill R Graff-Radford
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Dennis W Dickson
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
| | - Nilüfer Ertekin-Taner
- Form the Department of Neuroscience (M.A., S.J.L., M.C., J.O.W., M.M.C., J.S.R., J.D.B., T.N., K.M., D.W.D., N.E.-T.), Department of Neurology (N.R.G.-R., N.E.-T.), Mayo Clinic, Jacksonville, FL; and Department of Neurology (R.C.P.), Mayo Clinic, Rochester, MN
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79
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Röszer T. Transcriptional control of apoptotic cell clearance by macrophage nuclear receptors. Apoptosis 2016; 22:284-294. [DOI: 10.1007/s10495-016-1310-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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80
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Linton MF, Babaev VR, Huang J, Linton EF, Tao H, Yancey PG. Macrophage Apoptosis and Efferocytosis in the Pathogenesis of Atherosclerosis. Circ J 2016; 80:2259-2268. [PMID: 27725526 DOI: 10.1253/circj.cj-16-0924] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Macrophage apoptosis and the ability of macrophages to clean up dead cells, a process called efferocytosis, are crucial determinants of atherosclerosis lesion progression and plaque stability. Environmental stressors initiate endoplasmic reticulum (ER) stress and activate the unfolded protein response (UPR). Unresolved ER stress with activation of the UPR initiates apoptosis. Macrophages are resistant to apoptotic stimuli, because of activity of the PI3K/Akt pathway. Macrophages express 3 Akt isoforms, Akt1, Akt2 and Akt3, which are products of distinct but homologous genes. Akt displays isoform-specific effects on atherogenesis, which vary with different vascular cell types. Loss of macrophage Akt2 promotes the anti-inflammatory M2 phenotype and reduces atherosclerosis. However, Akt isoforms are redundant with regard to apoptosis. c-Jun NH2-terminal kinase (JNK) is a pro-apoptotic effector of the UPR, and the JNK1 isoform opposes anti-apoptotic Akt signaling. Loss of JNK1 in hematopoietic cells protects macrophages from apoptosis and accelerates early atherosclerosis. IκB kinase α (IKKα, a member of the serine/threonine protein kinase family) plays an important role in mTORC2-mediated Akt signaling in macrophages, and IKKα deficiency reduces macrophage survival and suppresses early atherosclerosis. Efferocytosis involves the interaction of receptors, bridging molecules, and apoptotic cell ligands. Scavenger receptor class B type I is a critical mediator of macrophage efferocytosis via the Src/PI3K/Rac1 pathway in atherosclerosis. Agonists that resolve inflammation offer promising therapeutic potential to promote efferocytosis and prevent atherosclerotic clinical events. (Circ J 2016; 80: 2259-2268).
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Affiliation(s)
- MacRae F Linton
- Atherosclerosis Research Unit, Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center
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ABCA7 Deficiency Accelerates Amyloid-β Generation and Alzheimer's Neuronal Pathology. J Neurosci 2016; 36:3848-59. [PMID: 27030769 DOI: 10.1523/jneurosci.3757-15.2016] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/22/2016] [Indexed: 02/08/2023] Open
Abstract
UNLABELLED In Alzheimer's disease (AD), the accumulation and deposition of amyloid-β (Aβ) peptides in the brain is a central event. Aβ is cleaved from amyloid precursor protein (APP) by β-secretase and γ-secretase mainly in neurons. Although mutations inAPP,PS1, orPS2cause early-onset familial AD,ABCA7encoding ATP-binding cassette transporter A7 is one of the susceptibility genes for late-onset AD (LOAD), in which itsloss-of-functionvariants increase the disease risk. ABCA7 is homologous to a major lipid transporter ABCA1 and is highly expressed in neurons and microglia in the brain. Here, we show that ABCA7 deficiency altered brain lipid profile and impaired memory in ABCA7 knock-out (Abca7(-/-)) mice. When bred to amyloid model APP/PS1 mice, plaque burden was exacerbated by ABCA7 deficit.In vivomicrodialysis studies indicated that the clearance rate of Aβ was unaltered. Interestingly, ABCA7 deletion facilitated the processing of APP to Aβ by increasing the levels of β-site APP cleaving enzyme 1 (BACE1) and sterol regulatory element-binding protein 2 (SREBP2) in primary neurons and mouse brains. Knock-down of ABCA7 expression in neurons caused endoplasmic reticulum stress highlighted by increased level of protein kinase R-like endoplasmic reticulum kinase (PERK) and increased phosphorylation of eukaryotic initiation factor 2α (eIF2α). In the brains of APP/PS1;Abca7(-/-)mice, the level of phosphorylated extracellular regulated kinase (ERK) was also significantly elevated. Together, our results reveal novel pathways underlying the association of ABCA7 dysfunction and LOAD pathogenesis. SIGNIFICANCE STATEMENT Gene variants inABCA7encoding ATP-binding cassette transporter A7 are associated with the increased risk for late-onset Alzheimer's disease (AD). Importantly, we found the altered brain lipid profile and impaired memory in ABCA7 knock-out mice. The accumulation of amyloid-β (Aβ) peptides cleaved from amyloid precursor protein (APP) in the brain is a key event in AD pathogenesis and we also found that ABCA7 deficit exacerbated brain Aβ deposition in amyloid AD model APP/PS1 mice. Mechanistically, we found that ABCA7 deletion facilitated the processing of APP and Aβ production by increasing the levels of β-secretase 1 (BACE1) in primary neurons and mouse brains without affecting the Aβ clearance rate in APP/PS1 mice. Our study demonstrates a novel mechanism underlying how dysfunctions of ABCA7 contribute to the risk for AD.
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Cervera-Carles L, Clarimón J. Genetic and Epigenetic Architecture of Alzheimer’s Dementia. CURRENT GENETIC MEDICINE REPORTS 2016. [DOI: 10.1007/s40142-016-0086-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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83
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Nuytemans K, Maldonado L, Ali A, John-Williams K, Beecham GW, Martin E, Scott WK, Vance JM. Overlap between Parkinson disease and Alzheimer disease in ABCA7 functional variants. Neurol Genet 2016; 2:e44. [PMID: 27066581 PMCID: PMC4817903 DOI: 10.1212/nxg.0000000000000044] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/17/2015] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Given their reported function in phagocytosis and clearance of protein aggregates in Alzheimer disease (AD), we hypothesized that variants in ATP-binding cassette transporter A7 (ABCA7) might be involved in Parkinson disease (PD). METHODS ABCA7 variants were identified using whole-exome sequencing (WES) on 396 unrelated patients with PD and 222 healthy controls. In addition, we used the publicly available WES data from the Parkinson's Progression Markers Initiative (444 patients and 153 healthy controls) as a second, independent data set. RESULTS We observed a higher frequency of loss-of-function (LOF) variants and rare putative highly functional variants (Combined Annotation Dependent Depletion [CADD] >20) in clinically diagnosed patients with PD than in healthy controls in both data sets. Overall, we identified LOF variants in 11 patients and 1 healthy control (odds ratio [OR] 4.94, Fisher exact p = 0.07). Four of these variants have been previously implicated in AD risk (p.E709AfsX86, p.W1214X, p.L1403RfsX7, and rs113809142). In addition, rare variants with CADD >20 were observed in 19 patients vs 3 healthy controls (OR 2.85, Fisher exact p = 0.06). CONCLUSION The presence of ABCA7 LOF variants in clinically defined PD suggests that they might be risk factors for neurodegeneration in general, especially those variants hallmarked by protein aggregation. More studies will be needed to evaluate the overall impact of this transporter in neurodegenerative disease.
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Affiliation(s)
- Karen Nuytemans
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - Lizmarie Maldonado
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - Aleena Ali
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - Krista John-Williams
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - Gary W Beecham
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - Eden Martin
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - William K Scott
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
| | - Jeffery M Vance
- John P. Hussman Institute for Human Genomics and The Morris K. Udall Parkinson Disease Center of Excellence, Miller School of Medicine, University of Miami, FL
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84
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Ramirez LM, Goukasian N, Porat S, Hwang KS, Eastman JA, Hurtz S, Wang B, Vang N, Sears R, Klein E, Coppola G, Apostolova LG. Common variants in ABCA7 and MS4A6A are associated with cortical and hippocampal atrophy. Neurobiol Aging 2015; 39:82-9. [PMID: 26923404 DOI: 10.1016/j.neurobiolaging.2015.10.037] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 10/01/2015] [Accepted: 10/30/2015] [Indexed: 12/25/2022]
Abstract
The precise physiologic function of many of the recently discovered Alzheimer's disease risk variants remains unknown. The downstream effects of genetic variants remain largely unexplored. We studied the relationship between the top 10 non-APOE genes with cortical and hippocampal atrophy as markers of neurodegeneration using 1.5T magnetic resonance imaging, 1-million single nucleotide polymorphism Illumina Human Omni-Quad array and Illumina Human BeadChip peripheral blood expression array data on 50 cognitively normal and 98 mild cognitive impairment subjects. After explicit matching of cortical and hippocampal morphology, we computed in 3D, the cortical thickness and hippocampal radial distance measures for each participant. Associations between the top 10 non-APOE genome-wide hits and neurodegeneration were explored using linear regression. Map-wise statistical significance was determined with permutations using threshold of p < 0.01. MS4A6A rs610932 and ABCA7 rs3764650 demonstrated significant associations with cortical and hippocampal atrophy. Exploratory MS4A6A and ABCA7 peripheral blood expression analyses revealed a similar pattern of associations with cortical neurodegeneration. To our knowledge, this is the first report of the effect of ABCA7 and MS4A6A on neurodegeneration.
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Affiliation(s)
| | | | - Shai Porat
- Department of Neurology, UCLA, Los Angeles, CA, USA
| | - Kristy S Hwang
- Oakland University William Beaumont School of Medicine, Rochester, MI, USA
| | | | - Sona Hurtz
- Drexel University College of Medicine, Philadelphia, PA, USA
| | | | - Nouchee Vang
- Department of Family Medicine, University of Minnesota, Twin Cities, MN, USA
| | - Renee Sears
- Department of Psychiatry, UCLA, Los Angeles, CA, USA
| | - Eric Klein
- Department of Psychiatry, UCLA, Los Angeles, CA, USA
| | | | - Liana G Apostolova
- Department of Neurology, UCLA, Los Angeles, CA, USA; Department of Neurology, Indiana University, Indianapolis, IN, USA; Department of Radiology and Imaging Sciences, Indiana University, Indianapolis, IN, USA; Department of Medical and Molecular Genetics, Indiana University, Indianapolis, IN, USA.
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Abstract
ATP-binding cassette transporter A7 (ABCA7) is highly expressed in the brain. Recent genome-wide association studies (GWAS) identify ABCA7 single nt polymorphisms (SNPs) that increase Alzheimer's disease (AD) risk. It is now important to understand the true function of ABCA7 in the AD context. We have begun to address this using in vitro and in vivo AD models. Our initial studies showed that transient overexpression of ABCA7 in Chinese hamster ovary cells stably expressing human amyloid precursor protein (APP) resulted in an approximate 50% inhibition in the production of the AD-related amyloid-β (Aβ) peptide as compared with mock-transfected cells. This increased ABCA7 expression was also associated with alterations in other markers of APP processing and an accumulation of cellular APP. To probe for a function of ABCA7 in vivo, we crossed Abca7−/− mice with J20 mice, an amyloidogenic transgenic AD mouse model [B6.Cg-Tg(PDGFB-APPSwInd)20Lms/J] expressing a mutant form of human APP bearing both the Swedish (K670N/M671L) and Indiana (V717F) familial AD mutations. We found that ABCA7 loss doubled insoluble Aβ levels and amyloid plaques in the brain. This did not appear to be related to changes in APP processing (C-terminal fragment analysis), which led us to assess other mechanism by which ABCA7 may modulate Aβ homoeostasis. As we have shown that microglia express high levels of ABCA7, we examined a role for ABCA7 in the phagocytic clearance of Aβ. Our data indicated that the capacity for bone marrow-derived macrophages derived from Abca7−/− mice to phagocytose Aβ was reduced by 51% compared with wild-type (WT) mice. This suggests ABCA7 plays a role in the regulation of Aβ homoeostasis in the brain and that this may be related to Aβ clearance by microglia.
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86
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Malik M, Parikh I, Vasquez JB, Smith C, Tai L, Bu G, LaDu MJ, Fardo DW, Rebeck GW, Estus S. Genetics ignite focus on microglial inflammation in Alzheimer's disease. Mol Neurodegener 2015; 10:52. [PMID: 26438529 PMCID: PMC4595327 DOI: 10.1186/s13024-015-0048-1] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 09/23/2015] [Indexed: 12/12/2022] Open
Abstract
In the past five years, a series of large-scale genetic studies have revealed novel risk factors for Alzheimer’s disease (AD). Analyses of these risk factors have focused attention upon the role of immune processes in AD, specifically microglial function. In this review, we discuss interpretation of genetic studies. We then focus upon six genes implicated by AD genetics that impact microglial function: TREM2, CD33, CR1, ABCA7, SHIP1, and APOE. We review the literature regarding the biological functions of these six proteins and their putative role in AD pathogenesis. We then present a model for how these factors may interact to modulate microglial function in AD.
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Affiliation(s)
- Manasi Malik
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, 800 S. Limestone St, Lexington, KY, 40536, USA.
| | - Ishita Parikh
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, 800 S. Limestone St, Lexington, KY, 40536, USA.
| | - Jared B Vasquez
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, 800 S. Limestone St, Lexington, KY, 40536, USA.
| | - Conor Smith
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, IL, USA.
| | - Leon Tai
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, IL, USA.
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA.
| | - Mary Jo LaDu
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, IL, USA.
| | - David W Fardo
- Department of Biostatistics and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA.
| | - G William Rebeck
- Department of Neuroscience, Georgetown University Medical Center, Washington, DC, USA.
| | - Steven Estus
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, 800 S. Limestone St, Lexington, KY, 40536, USA.
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Mhatre SD, Tsai CA, Rubin AJ, James ML, Andreasson KI. Microglial malfunction: the third rail in the development of Alzheimer's disease. Trends Neurosci 2015; 38:621-636. [PMID: 26442696 PMCID: PMC4670239 DOI: 10.1016/j.tins.2015.08.006] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/18/2015] [Accepted: 08/19/2015] [Indexed: 12/23/2022]
Abstract
Studies of Alzheimer's disease (AD) have predominantly focused on two major pathologies: amyloid-β (Aβ) and hyperphosphorylated tau. These misfolded proteins can accumulate asymptomatically in distinct regions over decades. However, significant Aβ accumulation can be seen in individuals who do not develop dementia, and tau pathology limited to the transentorhinal cortex, which can appear early in adulthood, is usually clinically silent. Thus, an interaction between these pathologies appears to be necessary to initiate and propel disease forward to widespread circuits. Recent multidisciplinary findings strongly suggest that the third factor required for disease progression is an aberrant microglial immune response. This response may initially be beneficial; however, a maladaptive microglial response eventually develops, fueling a feed-forward spread of tau and Aβ pathology.
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Affiliation(s)
- Siddhita D Mhatre
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA; Stanford Neurosciences Institute, Stanford, CA, USA
| | - Connie A Tsai
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA; Stanford Neurosciences Institute, Stanford, CA, USA; Neurosciences Graduate Program, Stanford University, Stanford, CA, USA
| | - Amanda J Rubin
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA; Stanford Neurosciences Institute, Stanford, CA, USA; Neurosciences Graduate Program, Stanford University, Stanford, CA, USA
| | - Michelle L James
- Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Katrin I Andreasson
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA; Stanford Neurosciences Institute, Stanford, CA, USA.
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88
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Zhang S, Yeap XY, Grigoryeva L, Dehn S, DeBerge M, Tye M, Rostlund E, Schrijvers D, Zhang ZJ, Sumagin R, Tourtellotte WG, Lee D, Lomasney J, Morrow J, Thorp EB. Cardiomyocytes induce macrophage receptor shedding to suppress phagocytosis. J Mol Cell Cardiol 2015; 87:171-9. [PMID: 26316303 DOI: 10.1016/j.yjmcc.2015.08.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/29/2015] [Accepted: 08/10/2015] [Indexed: 12/24/2022]
Abstract
BACKGROUND Mobilization of the innate immune response to clear and metabolize necrotic and apoptotic cardiomyocytes is a prerequisite to heart repair after cardiac injury. Suboptimal kinetics of dying myocyte clearance leads to secondary necrosis, and in the case of the heart, increased potential for collateral loss of neighboring non-regenerative myocytes. Despite the importance of myocyte phagocytic clearance during heart repair, surprisingly little is known about its underlying cell and molecular biology. OBJECTIVE To determine if phagocytic receptor MERTK is expressed in human hearts and to elucidate key sequential steps and phagocytosis efficiency of dying adult cardiomyocytes, by macrophages. RESULTS In infarcted human hearts, expression profiles of the phagocytic receptor MER-tyrosine kinase (MERTK) mimicked that found in experimental ischemic mouse hearts. Electron micrographs of myocardium identified MERTK signal along macrophage phagocytic cups and Mertk-/- macrophages contained reduced digested myocyte debris after myocardial infarction. Ex vivo co-culture of primary macrophages and adult cardiomyocyte apoptotic bodies revealed reduced engulfment relative to resident cardiac fibroblasts. Inefficient clearance was not due to the larger size of myocyte apoptotic bodies, nor were other key steps preceding the formation of phagocytic synapses significantly affected; this included macrophage chemotaxis and direct binding of phagocytes to myocytes. Instead, suppressed phagocytosis was directly associated with myocyte-induced inactivation of MERTK, which was partially rescued by genetic deletion of a MERTK proteolytic susceptibility site. CONCLUSION Utilizing an ex vivo co-cultivation approach to model key cellular and molecular events found in vivo during infarction, cardiomyocyte phagocytosis was found to be inefficient, in part due to myocyte-induced shedding of macrophage MERTK. These findings warrant future studies to identify other cofactors of macrophage-cardiomyocyte cross-talk that contribute to cardiac pathophysiology.
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Affiliation(s)
- Shuang Zhang
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Xin-Yi Yeap
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Lubov Grigoryeva
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Shirley Dehn
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Matthew DeBerge
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Michael Tye
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Emily Rostlund
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | | | | | - Ronen Sumagin
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA
| | - Warren G Tourtellotte
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - Daniel Lee
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA
| | - Jon Lomasney
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - John Morrow
- Department of Cardiology and Division of Molecular Medicine, Columbia University, New York, NY, USA
| | - Edward B Thorp
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL, USA; Surgery-Organ Transplantation, Northwestern University, Chicago, IL, USA.
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Satoh K, Abe-Dohmae S, Yokoyama S, St George-Hyslop P, Fraser PE. ATP-binding cassette transporter A7 (ABCA7) loss of function alters Alzheimer amyloid processing. J Biol Chem 2015; 290:24152-65. [PMID: 26260791 DOI: 10.1074/jbc.m115.655076] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Indexed: 11/06/2022] Open
Abstract
The ATP-binding cassette transporter A7 (ABCA7) has been identified as a susceptibility factor of late onset Alzheimer disease in genome-wide association studies. ABCA7 has been shown to mediate phagocytosis and affect membrane trafficking. The current study examined the impact of ABCA7 loss of function on amyloid precursor protein (APP) processing and generation of amyloid-β (Aβ). Suppression of endogenous ABCA7 in several different cell lines resulted in increased β-secretase cleavage and elevated Aβ. ABCA7 knock-out mice displayed an increased production of endogenous murine amyloid Aβ42 species. Crossing ABCA7-deficient animals to an APP transgenic model resulted in significant increases in the soluble Aβ as compared with mice expressing normal levels of ABCA7. Only modest changes in the amount of insoluble Aβ and amyloid plaque densities were observed once the amyloid pathology was well developed, whereas Aβ deposition was enhanced in younger animals. In vitro studies indicated a more rapid endocytosis of APP in ABCA7 knock-out cells that is mechanistically consistent with the increased Aβ production. These in vitro and in vivo findings indicate a direct role of ABCA7 in amyloid processing that may be associated with its primary biological function to regulate endocytic pathways. Several potential loss-of-function ABCA7 mutations and deletions linked to Alzheimer disease that in some instances have a greater impact than apoE allelic variants have recently been identified. A reduction in ABCA7 expression or loss of function would be predicted to increase amyloid production and that may be a contributing factor in the associated Alzheimer disease susceptibility.
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Affiliation(s)
- Kanayo Satoh
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada,
| | - Sumiko Abe-Dohmae
- Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya 467-8601, Japan
| | - Shinji Yokoyama
- Nutritional Health Science Research Center, Chubu University, Matsumoto-cho 1200, Kasugai 487-8501, Japan
| | - Peter St George-Hyslop
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada, Departments of Medicine (Neurology) and Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada, and Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - Paul E Fraser
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada, Departments of Medicine (Neurology) and Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada, and
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90
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Mutations in ABCA7 in a Belgian cohort of Alzheimer's disease patients: a targeted resequencing study. Lancet Neurol 2015; 14:814-822. [DOI: 10.1016/s1474-4422(15)00133-7] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 12/23/2022]
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91
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Co-receptors are dispensable for tethering receptor-mediated phagocytosis of apoptotic cells. Cell Death Dis 2015; 6:e1772. [PMID: 26018733 PMCID: PMC4669715 DOI: 10.1038/cddis.2015.140] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 04/24/2015] [Accepted: 04/28/2015] [Indexed: 12/11/2022]
Abstract
During efferocytosis, phagocytic cells recognize dying cells by receptors binding to ligands specifically exposed on apoptotic cells. Multiple phagocytic receptors and some of their signaling pathways have been identified. However, the downstream pathways of tethering receptors that secure apoptotic cells remain elusive. It is generally assumed that tethering receptors induce signaling to mediate engulfment via interacting with co-receptors or other engulfment receptors located nearby. However, it is poorly understood whether co-receptors for tethering receptors exist during efferocytosis, and, if they do, whether they are indispensable for this process. Here, we address this issue using glycophosphatidylinositol (GPI)-anchored annexin A5 (Anxa5-GPI), an artificial tethering receptor without a putative co-receptor. Phagocytes expressing Anxa5-GPI exhibited enhanced binding of apoptotic cells, resulting in promoted ingestion of apoptotic cells in a phosphatidylserine-dependent manner. Anxa5-GPI-induced phagocytosis of apoptotic cells relied on the known cytoskeletal engulfment machinery but partially depended on the Elmo-Dock-Rac module or the integrin pathway. In addition, Anxa5-GPI-mediated efferocytosis provoked anti-inflammatory responses. Taken together, our work suggests that co-receptors are dispensable for tethering receptor-induced efferocytosis and that tethering receptors mediate the engulfment of apoptotic cells through multiple engulfment signaling pathways.
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92
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Steinberg S, Stefansson H, Jonsson T, Johannsdottir H, Ingason A, Helgason H, Sulem P, Magnusson OT, Gudjonsson SA, Unnsteinsdottir U, Kong A, Helisalmi S, Soininen H, Lah JJ, Aarsland D, Fladby T, Ulstein ID, Djurovic S, Sando SB, White LR, Knudsen GP, Westlye LT, Selbæk G, Giegling I, Hampel H, Hiltunen M, Levey AI, Andreassen OA, Rujescu D, Jonsson PV, Bjornsson S, Snaedal J, Stefansson K. Loss-of-function variants in ABCA7 confer risk of Alzheimer's disease. Nat Genet 2015; 47:445-7. [PMID: 25807283 DOI: 10.1038/ng.3246] [Citation(s) in RCA: 241] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Accepted: 02/13/2015] [Indexed: 12/12/2022]
Abstract
We conducted a search for rare, functional variants altering susceptibility to Alzheimer's disease that exploited knowledge of common variants associated with the same disease. We found that loss-of-function variants in ABCA7 confer risk of Alzheimer's disease in Icelanders (odds ratio (OR) = 2.12, P = 2.2 × 10(-13)) and discovered that the association replicated in study groups from Europe and the United States (combined OR = 2.03, P = 6.8 × 10(-15)).
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Seppo Helisalmi
- 1] Institute of Clinical Medicine-Neurology, University of Eastern Finland, Kuopio, Finland. [2] NeuroCenter, Kuopio University Hospital, Kuopio, Finland
| | - Hilkka Soininen
- 1] Institute of Clinical Medicine-Neurology, University of Eastern Finland, Kuopio, Finland. [2] NeuroCenter, Kuopio University Hospital, Kuopio, Finland
| | - James J Lah
- School of Medicine, Emory University, Atlanta, Georgia, USA
| | | | - Dag Aarsland
- 1] Alzheimer's Disease Research Centre, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden. [2] Center for Age-Related Diseases, Stavanger University Hospital, Stavanger, Norway. [3] Institute of Clinical Medicine, Division of Medicine and Laboratory Sciences, University of Oslo, Oslo, Norway
| | - Tormod Fladby
- 1] Institute of Clinical Medicine, Division of Medicine and Laboratory Sciences, University of Oslo, Oslo, Norway. [2] Department of Neurology, Akershus University Hospital, Lørenskog, Norway
| | - Ingun D Ulstein
- 1] Department of Psychiatry of Old Age, Oslo University Hospital, Oslo, Norway. [2] Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Srdjan Djurovic
- 1] Department of Medical Genetics, Oslo University Hospital, Oslo, Norway. [2] NORMENT-K.G. Jebsen Centre, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Sigrid B Sando
- 1] Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway. [2] Department of Neurology, St. Olav's Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Linda R White
- 1] Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway. [2] Department of Neurology, St. Olav's Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Gun-Peggy Knudsen
- Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Lars T Westlye
- 1] NORMENT-K.G. Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. [2] Department of Psychology, University of Oslo, Oslo, Norway
| | - Geir Selbæk
- Ageing and Health, Norwegian Centre for Research, Education and Service Development, Vestfold Hospital Trust, Tønsberg, Norway
| | - Ina Giegling
- Department of Psychiatry, University of Halle, Halle, Germany
| | - Harald Hampel
- Sorbonne Universités, Université Pierre et Marie Curie, Département de Neurologie, Hôpital Pitié Salpêtrière, Paris, France
| | - Mikko Hiltunen
- 1] Institute of Clinical Medicine-Neurology, University of Eastern Finland, Kuopio, Finland. [2] NeuroCenter, Kuopio University Hospital, Kuopio, Finland. [3] Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
| | - Allan I Levey
- School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Ole A Andreassen
- 1] NORMENT-K.G. Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. [2] NORMENT-K.G. Jebsen Centre, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Dan Rujescu
- Department of Psychiatry, University of Halle, Halle, Germany
| | - Palmi V Jonsson
- 1] Faculty of Medicine, University of Iceland, Reykjavik, Iceland. [2] Department of Geriatric Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - Sigurbjorn Bjornsson
- Department of Geriatric Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - Jon Snaedal
- Department of Geriatric Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - Kari Stefansson
- 1] deCODE Genetics, Reykjavik, Iceland. [2] Faculty of Medicine, University of Iceland, Reykjavik, Iceland
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93
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Karch CM, Goate AM. Alzheimer's disease risk genes and mechanisms of disease pathogenesis. Biol Psychiatry 2015; 77:43-51. [PMID: 24951455 PMCID: PMC4234692 DOI: 10.1016/j.biopsych.2014.05.006] [Citation(s) in RCA: 855] [Impact Index Per Article: 95.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 04/30/2014] [Accepted: 05/05/2014] [Indexed: 01/18/2023]
Abstract
We review the genetic risk factors for late-onset Alzheimer's disease (AD) and their role in AD pathogenesis. More recent advances in understanding of the human genome-technologic advances in methods to analyze millions of polymorphisms in thousands of subjects-have revealed new genes associated with AD risk, including ABCA7, BIN1, CASS4, CD33, CD2AP, CELF1, CLU, CR1, DSG2, EPHA1, FERMT2, HLA-DRB5-DBR1, INPP5D, MS4A, MEF2C, NME8, PICALM, PTK2B, SLC24H4-RIN3, SORL1, and ZCWPW1. Emerging technologies to analyze the entire genome in large data sets have also revealed coding variants that increase AD risk: PLD3 and TREM2. We review the relationship between these AD risk genes and the cellular and neuropathologic features of AD. Understanding the mechanisms underlying the association of these genes with risk for disease will provide the most meaningful targets for therapeutic development to date.
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Affiliation(s)
| | - Alison M. Goate
- Corresponding author Contact information: Department of Psychiatry, Washington University School of Medicine, 425 S. Euclid Ave, Campus Box 8134, St. Louis, MO 63110, phone: 314-362-8691, fax: 314-747-2983,
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94
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Lleo A, Zhang W, McDonald WH, Seeley EH, Leung PS, Coppel RL, Ansari AA, Adams DH, Afford S, Invernizzi P, Gershwin ME. Shotgun proteomics: identification of unique protein profiles of apoptotic bodies from biliary epithelial cells. Hepatology 2014; 60:1314-23. [PMID: 24841946 PMCID: PMC4175017 DOI: 10.1002/hep.27230] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 05/16/2014] [Indexed: 01/06/2023]
Abstract
UNLABELLED Shotgun proteomics is a powerful analytic method to characterize complex protein mixtures in combination with multidimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS). We used this platform for proteomic characterization of apoptotic bodies in an effort to define the complex protein mixtures found in primary cultures of human intrahepatic biliary epithelial cells (HiBEC), human renal proximal tubular epithelial cells, human bronchial epithelial cells, isolated intrahepatic biliary epithelial cells from explanted primary biliary cirrhosis (PBC), and control liver using a total of 24 individual samples. Further, as additional controls and for purposes of comparison, proteomic signatures were also obtained from intact cells and apoptotic bodies. The data obtained from LC-MS/MS, combined with database searches and protein assembly algorithms, allowed us to address significant differences in protein spectral counts and identify unique pathways that may be a component of the induction of the signature inflammatory cytokine response against BECs, including the Notch signaling pathway, interleukin (IL)8, IL6, CXCR2, and integrin signaling. Indeed, there are 11 proteins that localize specifically to apoptotic bodies of HiBEC and eight proteins that were specifically absent in HiBEC apoptotic bodies. CONCLUSION Proteomic analysis of BECs from PBC liver compared to normal liver are significantly different, suggesting that an immunological attack affects the repertoire of proteins expressed and that such cells should be thought of as living in an environment undergoing continuous selection secondary to an innate and adaptive immune response, reflecting an almost "Darwinian" bias.
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Affiliation(s)
- Ana Lleo
- Liver Unit and Center for Autoimmune Liver Diseases, Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | - Weici Zhang
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA, USA
| | - W. Hayes McDonald
- Mass Spectrometry Research Center and Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Erin H. Seeley
- Mass Spectrometry Research Center and Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Patrick S.C. Leung
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA, USA
| | - Ross L. Coppel
- Department of Medical Microbiology, Monash University, Melbourne, Australia
| | - Aftab A. Ansari
- Department of Pathology, Emory University School of Medicine, Atlanta, GA, USA
| | - David H. Adams
- Centre for Liver Research and NIHR Biomedical Research Unit in Liver Disease, Institute of Biomedical Research, University of Birmingham, Birmingham, UK
| | - Simon Afford
- Centre for Liver Research and NIHR Biomedical Research Unit in Liver Disease, Institute of Biomedical Research, University of Birmingham, Birmingham, UK
| | - Pietro Invernizzi
- Liver Unit and Center for Autoimmune Liver Diseases, Humanitas Clinical and Research Center, Rozzano (MI), Italy,Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA, USA
| | - M. Eric Gershwin
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA, USA
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95
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Murakami Y, Tian L, Voss OH, Margulies DH, Krzewski K, Coligan JE. CD300b regulates the phagocytosis of apoptotic cells via phosphatidylserine recognition. Cell Death Differ 2014; 21:1746-57. [PMID: 25034781 DOI: 10.1038/cdd.2014.86] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/14/2014] [Accepted: 05/21/2014] [Indexed: 01/15/2023] Open
Abstract
The CD300 receptor family members are a group of molecules that modulate a variety of immune cell processes. We show that mouse CD300b (CLM7/LMIR5), expressed on myeloid cells, recognizes outer membrane-exposed phosphatidylserine (PS) and does not, as previously reported, directly recognize TIM1 or TIM4. CD300b accumulates in phagocytic cups along with F-actin at apoptotic cell contacts, thereby facilitating their engulfment. The CD300b-mediated activation signal is conveyed through CD300b association with the adaptor molecule DAP12, and requires a functional DAP12 ITAM motif. Binding of apoptotic cells promotes the activation of the PI3K-Akt kinase pathway in macrophages, while silencing of CD300b expression diminishes PI3K-Akt kinase activation and impairs efferocytosis. Collectively, our data show that CD300b recognizes PS as a ligand, and regulates the phagocytosis of apoptotic cells via the DAP12 signaling pathway.
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Affiliation(s)
- Y Murakami
- Receptor Cell Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - L Tian
- Receptor Cell Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - O H Voss
- Receptor Cell Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - D H Margulies
- Molecular Biology Section, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - K Krzewski
- Receptor Cell Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - J E Coligan
- Receptor Cell Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
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96
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Zhao QF, Yu JT, Tan MS, Tan L. ABCA7 in Alzheimer's Disease. Mol Neurobiol 2014; 51:1008-16. [PMID: 24878767 DOI: 10.1007/s12035-014-8759-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Accepted: 05/21/2014] [Indexed: 12/20/2022]
Abstract
ATP-binding cassette A7 (ABCA7) gene has recently been identified as a strong genetic locus associated with late-onset Alzheimer's disease (LOAD) through genome-wide association studies (GWASs). ABCA7 is a member of the ATP-binding cassette (ABC) transporter gene superfamily, which codes for 49 ABC proteins, divided into 7 subfamilies (coded A-G). As a multispan transmembrane protein, ABCA7 is most abundantly expressed in the microglial cells in the brain. The levels of ABCA7 have been detected to be increased in the Alzheimer's disease (AD) brain, which positively correlated with amyloid plaque burden and disease severity. Emerging data suggests that ABCA7 could be associated with AD via various pathways, possibly including amyloid-β (Aβ) accumulation, lipid metabolism, and phagocytosis. In this review, we summarize the known functions of ABCA7 and discuss the single-nucleotide polymorphisms (SNPs) related to LOAD, as well as their potential physiological effects. Finally, given the contributions of ABCA7 to AD pathogenesis, targeting ABCA7 might provide novel opportunities for AD therapy.
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Affiliation(s)
- Qing-Fei Zhao
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
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97
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Kanekiyo T, Bu G. The low-density lipoprotein receptor-related protein 1 and amyloid-β clearance in Alzheimer's disease. Front Aging Neurosci 2014; 6:93. [PMID: 24904407 PMCID: PMC4033011 DOI: 10.3389/fnagi.2014.00093] [Citation(s) in RCA: 188] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 04/28/2014] [Indexed: 11/24/2022] Open
Abstract
Accumulation and aggregation of amyloid-β (Aβ) peptides in the brain trigger the development of progressive neurodegeneration and dementia associated with Alzheimer’s disease (AD). Perturbation in Aβ clearance, rather than Aβ production, is likely the cause of sporadic, late-onset AD, which accounts for the majority of AD cases. Since cellular uptake and subsequent degradation constitute a major Aβ clearance pathway, the receptor-mediated endocytosis of Aβ has been intensely investigated. Among Aβ receptors, the low-density lipoprotein receptor-related protein 1 (LRP1) is one of the most studied receptors. LRP1 is a large endocytic receptor for more than 40 ligands, including apolipoprotein E, α2-macroglobulin and Aβ. Emerging in vitro and in vivo evidence demonstrates that LRP1 is critically involved in brain Aβ clearance. LRP1 is highly expressed in a variety of cell types in the brain including neurons, vascular cells and glial cells, where LRP1 functions to maintain brain homeostasis and control Aβ metabolism. LRP1-mediated endocytosis regulates cellular Aβ uptake by binding to Aβ either directly or indirectly through its co-receptors or ligands. Furthermore, LRP1 regulates several signaling pathways, which also likely influences Aβ endocytic pathways. In this review, we discuss how LRP1 regulates the brain Aβ clearance and how this unique endocytic receptor participates in AD pathogenesis. Understanding of the mechanisms underlying LRP1-mediated Aβ clearance should enable the rational design of novel diagnostic and therapeutic strategies for AD.
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Affiliation(s)
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville FL, USA
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98
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Liao YC, Lee WJ, Hwang JP, Wang YF, Tsai CF, Wang PN, Wang SJ, Fuh JL. ABCA7 gene and the risk of Alzheimer's disease in Han Chinese in Taiwan. Neurobiol Aging 2014; 35:2423.e7-2423.e13. [PMID: 24908168 DOI: 10.1016/j.neurobiolaging.2014.05.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 04/29/2014] [Accepted: 05/05/2014] [Indexed: 10/25/2022]
Abstract
The ATP-binding cassette, subfamily A, member 7 gene (ABCA7) was recently identified as a susceptible gene of Alzheimer's disease (AD) in the Caucasian population and African Americans. To test its genetic effect in the Han-Chinese population, 536 AD cases and 307 cognitive-intact, elder controls were genotyped for ABCA7 rs3764650 and apolipoprotein E (APOE) ε2/ε3/ε4 alleles. Global cognitive performance was assessed by the Mini-Mental State Examination in both AD patients and controls. For AD patients, comprehensive evaluation of each cognitive domain was further conducted as the following: (1) attention (forward and backward digit span); (2) memory (12-item word recall test); (3) executive function (category verbal fluency); (4) processing speed (Trail making test, part A); and (5) naming task (Boston naming test). ABCA7 rs3764650 was significantly associated with AD and the GG genotype carried a reduced risk for AD (odds ratio = 0.52, p = 0.0026). The association was further confirmed in 1802 population-based, healthy controls from Taiwan Biobank as a replicate (odds ratio = 0.70, p = 0.032). After adjustment of age, sex, and APOE ε4 allele, rs3764650 remained to be an independent predictor of AD (p = 0.001). The influence of ABCA7 was only evident in individuals without APOE ε4 alleles (p = 0.0004) but absent in ε4 carriers (p = 0.91). None of the cognitive tests was related to ABCA7 rs3764650 genotypes. The minor allele frequency and effect size of rs3764650 disclosed in the Han-Chinese population differed from those reported in the Caucasians and African Americans. Further studies were warranted to elucidate ABCA7's effect among different ethnic groups.
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Affiliation(s)
- Yi-Chu Liao
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Wei-Ju Lee
- Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Neurology, Neurological Institute, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Jeng-Ping Hwang
- Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Yen-Feng Wang
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Brain Research Center, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Chia-Fen Tsai
- Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Pei-Ning Wang
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Brain Research Center, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Shuu-Jiun Wang
- Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Brain Research Center, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
| | - Jong-Ling Fuh
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Brain Research Center, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
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99
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Chung SJ, Kim MJ, Kim YJ, Kim J, You S, Jang EH, Kim SY, Lee JH. CR1, ABCA7, and APOE genes affect the features of cognitive impairment in Alzheimer's disease. J Neurol Sci 2014; 339:91-6. [PMID: 24530172 DOI: 10.1016/j.jns.2014.01.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 01/18/2014] [Accepted: 01/22/2014] [Indexed: 11/18/2022]
Abstract
BACKGROUND The genetic factors that determine the heterogeneity of cognitive impairment in Alzheimer's disease (AD) patients have been rarely reported. We aimed to investigate the association between top hits of genome-wide association studies (GWAS) and specific cognitive domains in AD patients. METHODS We investigated 86 single nucleotide polymorphisms (SNPs) selected from 12 genes (ABCA7, APOE, BIN1, CD2AP, CD33, CLU, CR1, EPHA1, LRAT, MS4A6A, PCDH11X, and PICALM) based on results of the recent GWAS and genotyped in 211 AD cases. We also analyzed results of comprehensive neuropsychological evaluations in all cases. We performed multiple regression analyses. RESULTS There were four significant associations between genotypes and phenotypes of AD patients: CR1 SNP rs11803956 correlated with Mini-Mental State Examination (MMSE) score (β=1.718, Pcorrected=0.002); ABCA7 SNP rs3752232 correlated with Rey Complex Figure Test (RCFT) copy score (β=-6.861, Pcorrected=0.013); APOE SNP rs2075650 correlated with the percentile of RCFT copy score (β=14.005, Pcorrected=0.021) and the percentile of total score in phonemic fluency (β=11.052, Pcorrected=0.035). CONCLUSION Our results suggest that CR1, ABCA7, and APOE correlate with specific aspects of cognitive impairments in AD patients.
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Affiliation(s)
- Sun Ju Chung
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
| | - Mi-Jung Kim
- Department of Neurology, Bobath Memorial Hospital, Seongnam, Republic of Korea
| | - Young Jin Kim
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Juyeon Kim
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sooyeoun You
- Department of Neurology, Dongsan Medical Center, Keimyung University, Daegu, Republic of Korea
| | - Eun Hye Jang
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seong Yoon Kim
- Department of Psychiatry, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jae-Hong Lee
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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100
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Liu B, Zhang B, Guo R, Li S, Xu Y. Enhancement in efferocytosis of oxidized low-density lipoprotein-induced apoptotic RAW264.7 cells through Sirt1-mediated autophagy. Int J Mol Med 2013; 33:523-33. [PMID: 24378473 PMCID: PMC3926501 DOI: 10.3892/ijmm.2013.1609] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Accepted: 12/16/2013] [Indexed: 12/19/2022] Open
Abstract
Macrophages play a key role in atherosclerotic plaque formation and rupture. These phagocytic cells are important in the scavenging of modified lipoproteins, unwanted or dead cells and cellular debris through efferocytosis. Sirtuin1 (Sirt1), a member of the conserved sirtuin family and a key regulator in the progression of atherosclerosis exerts protective effects by regulating autophagy, a well-known survival mechanism. Inhibition of autophagy may also result in defective efferocytosis. This study aimed to investigate the effect of Sirt1 on the efferocytosis of oxidized low-density lipoprotein (ox-LDL)-induced apoptotic RAW264.7 cells through upregulation of autophagy. The apoptotic cells were incubated with high and low concentrations of Sirt1 activator resveratrol (RSV) and Sirt1 inhibitor nicotinamide (NAM) as well as autophagy inhibitor 3-methyladenine (3-MA) + low concentration RSV. Apoptosis was determined by flow cytometry (FCM) of annexin-V/propidium iodide (AV/PI) dual staining. Total proteins were extracted and protein levels were detected through western blot analysis. The ox-LDL uptake and efferocytosis of apoptotic RAW264.7 cells were detected by oil red O staining and calculation of the phagocytic index of apoptotic RAW264.7 cells. The expression of Sirt1 and autophagy marker proteins was simultaneously increased with the stimulation of low concentration RSV (all P<0.05) and decreased in low and high NAM groups (all P<0.05), compared with the control group. Efferocytosis was highest in the low concentration RSV group (P<0.001) and relatively lower in the low and high concentration NAM groups (both P<0.05) compared with the control group, which was similar to the change in the expression of Sirt1 and autophagy marker proteins. The results showed that the efferocytosis of apoptotic RAW264.7 cells was significantly improved with the upregulation of Sirt1-mediated autophagy. Therefore, Sirt1 may serve as a novel therapeutic target for the treatment of atherosclerosis.
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Affiliation(s)
- Baoxin Liu
- Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, P.R. China
| | - Buchun Zhang
- Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, P.R. China
| | - Rong Guo
- Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, P.R. China
| | - Shuang Li
- Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, P.R. China
| | - Yawei Xu
- Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, P.R. China
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