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Paul D, Agrawal R, Singh S. Alzheimer's disease and clinical trials. J Basic Clin Physiol Pharmacol 2024; 35:31-44. [PMID: 38491747 DOI: 10.1515/jbcpp-2023-0264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 02/28/2024] [Indexed: 03/18/2024]
Abstract
Alzheimer's disease (AD) is spreading its root disproportionately among the worldwide population. Many genes have been identified as the hallmarks of AD. Based upon the knowledge, many clinical trials have been designed and conducted. Attempts have been made to alleviate the pathology associated with AD by targeting the molecular products of these genes. Irrespective of the understanding on the genetic component of AD, many clinical trials have failed and imposed greater challenges on the path of drug discovery. Therefore, this review aims to identify research and review articles to pinpoint the limitations of drug candidates (thiethylperazine, CT1812, crenezumab, CNP520, and lecanemab), which are under or withdrawn from clinical trials. Thorough analysis of the cross-talk pathways led to the identification of many confounding factors, which could interfere with the success of clinical trials with drug candidates such as thiethylperazine, CT1812, crenezumab, and CNP520. Though these drug candidates were enrolled in clinical trials, yet literature review shows many limitations. These limitations raise many questions on the rationale behind the enrollments of these drug candidates in clinical trials. A meticulous prior assessment of the outcome of clinical studies may stop risky clinical trials at their inceptions. This may save time, money, and resources.
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Affiliation(s)
- Deepraj Paul
- Department of Pharmacology, 621320 College of Pharmacy JSS Academy of Technical Education , Noida, Uttar Pradesh, India
| | - Rohini Agrawal
- Department of Pharmacology, 621320 College of Pharmacy JSS Academy of Technical Education , Noida, Uttar Pradesh, India
| | - Swati Singh
- Department of Pharmacology, 621320 College of Pharmacy JSS Academy of Technical Education , Noida, Uttar Pradesh, India
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2
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Lee WP, Wang H, Dombroski B, Cheng PL, Tucci A, Si YQ, Farrell J, Tzeng JY, Leung YY, Malamon J, Wang LS, Vardarajan B, Farrer L, Schellenberg G. Structural Variation Detection and Association Analysis of Whole-Genome-Sequence Data from 16,905 Alzheimer's Diseases Sequencing Project Subjects. RESEARCH SQUARE 2023:rs.3.rs-3353179. [PMID: 37886469 PMCID: PMC10602095 DOI: 10.21203/rs.3.rs-3353179/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Structural variations (SVs) are important contributors to the genetics of human diseases. However, their role in Alzheimer's disease (AD) remains largely unstudied due to challenges in accurately detecting SVs. We analyzed whole-genome sequencing data from the Alzheimer's Disease Sequencing Project (N = 16,905) and identified 400,234 (168,223 high-quality) SVs. Laboratory validation yielded a sensitivity of 82% (85% for high-quality). We found a significant burden of deletions and duplications in AD cases, particularly for singletons and homozygous events. On AD genes, we observed the ultra-rare SVs associated with the disease, including protein-altering SVs in ABCA7, APP, PLCG2, and SORL1. Twenty-one SVs are in linkage disequilibrium (LD) with known AD-risk variants, exemplified by a 5k deletion in complete LD with rs143080277 in NCK2. We also identified 16 SVs associated with AD and 13 SVs linked to AD-related pathological/cognitive endophenotypes. This study highlights the pivotal role of SVs in shaping our understanding of AD genetics.
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3
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Fedele E. Anti-Amyloid Therapies for Alzheimer's Disease and the Amyloid Cascade Hypothesis. Int J Mol Sci 2023; 24:14499. [PMID: 37833948 PMCID: PMC10578107 DOI: 10.3390/ijms241914499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 09/22/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023] Open
Abstract
Over the past 30 years, the majority of (pre)clinical efforts to find an effective therapy for Alzheimer's disease (AD) focused on clearing the β-amyloid peptide (Aβ) from the brain since, according to the amyloid cascade hypothesis, the peptide was (and it is still considered by many) the pathogenic determinant of this neurodegenerative disorder. However, as reviewed in this article, results from the numerous clinical trials that have tested anti-Aβ therapies to date indicate that this peptide plays a minor role in the pathogenesis of AD. Indeed, even Aducanumab and Lecanemab, the two antibodies recently approved by the FDA for AD therapy, as well as Donanemab showed limited efficacy on cognitive parameters in phase III clinical trials, despite their capability of markedly lowering Aβ brain load. Furthermore, preclinical evidence demonstrates that Aβ possesses several physiological functions, including memory formation, suggesting that AD may in part be due to a loss of function of this peptide. Finally, it is generally accepted that AD could be the result of many molecular dysfunctions, and therefore, if we keep chasing only Aβ, it means that we cannot see the forest for the trees.
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Affiliation(s)
- Ernesto Fedele
- Pharmacology and Toxicology Unit, Department of Pharmacy, School of Medical and Pharmaceutical Sciences, University of Genoa, Viale Cembrano 4, 16148 Genoa, Italy;
- IRCCS Ospedale Policlinico San Martino, 16132 Genoa, Italy
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4
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Wang H, Dombroski BA, Cheng PL, Tucci A, Si YQ, Farrell JJ, Tzeng JY, Leung YY, Malamon JS, Wang LS, Vardarajan BN, Farrer LA, Schellenberg GD, Lee WP. Structural Variation Detection and Association Analysis of Whole-Genome-Sequence Data from 16,905 Alzheimer's Diseases Sequencing Project Subjects. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.09.13.23295505. [PMID: 37745545 PMCID: PMC10516060 DOI: 10.1101/2023.09.13.23295505] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Structural variations (SVs) are important contributors to the genetics of numerous human diseases. However, their role in Alzheimer's disease (AD) remains largely unstudied due to challenges in accurately detecting SVs. Here, we analyzed whole-genome sequencing data from the Alzheimer's Disease Sequencing Project (ADSP, N=16,905 subjects) and identified 400,234 (168,223 high-quality) SVs. We found a significant burden of deletions and duplications in AD cases (OR=1.05, P=0.03), particularly for singletons (OR=1.12, P=0.0002) and homozygous events (OR=1.10, P<0.0004). On AD genes, the ultra-rare SVs, including protein-altering SVs in ABCA7, APP, PLCG2, and SORL1, were associated with AD (SKAT-O P=0.004). Twenty-one SVs are in linkage disequilibrium (LD) with known AD-risk variants, e.g., a deletion (chr2:105731359-105736864) in complete LD (R2=0.99) with rs143080277 (chr2:105749599) in NCK2. We also identified 16 SVs associated with AD and 13 SVs associated with AD-related pathological/cognitive endophenotypes. Our findings demonstrate the broad impact of SVs on AD genetics.
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Affiliation(s)
- Hui Wang
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
| | - Beth A Dombroski
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
| | - Po-Liang Cheng
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
| | - Albert Tucci
- Bioinformatics Research Center, North Carolina State University, NC 27695, USA
| | - Ya-Qin Si
- Bioinformatics Research Center, North Carolina State University, NC 27695, USA
| | - John J Farrell
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, MA 02118, USA
| | - Jung-Ying Tzeng
- Bioinformatics Research Center, North Carolina State University, NC 27695, USA
| | - Yuk Yee Leung
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
| | - John S Malamon
- Department of Surgery, Scholl of Medicine, University of Colorado, CO 80045, USA
| | - Li-San Wang
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
| | - Badri N Vardarajan
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, NY 10032, USA
- Department of Neurology, College of Physicians and Surgeons, Columbia University and the New York Presbyterian Hospital, NY 10032, USA
| | - Lindsay A Farrer
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, MA 02118, USA
- Department of Neurology, Boston University School of Medicine, MA 02118, USA
- Department of Ophthalmology, Boston University School of Medicine, MA 02118, USA
- Department of Biostatistics, Boston University School of Public Health, MA 02118, USA
- Department of Epidemiology, Boston University School of Public Health, MA 02118, USA
| | - Gerard D Schellenberg
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
| | - Wan-Ping Lee
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, PA 19104, USA
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5
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Littman R, Cheng M, Wang N, Peng C, Yang X. SCING: Inference of robust, interpretable gene regulatory networks from single cell and spatial transcriptomics. iScience 2023; 26:107124. [PMID: 37434694 PMCID: PMC10331489 DOI: 10.1016/j.isci.2023.107124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 03/31/2023] [Accepted: 06/09/2023] [Indexed: 07/13/2023] Open
Abstract
Gene regulatory network (GRN) inference is an integral part of understanding physiology and disease. Single cell/nuclei RNA-seq (scRNA-seq/snRNA-seq) data has been used to elucidate cell-type GRNs; however, the accuracy and speed of current scRNAseq-based GRN approaches are suboptimal. Here, we present Single Cell INtegrative Gene regulatory network inference (SCING), a gradient boosting and mutual information-based approach for identifying robust GRNs from scRNA-seq, snRNA-seq, and spatial transcriptomics data. Performance evaluation using Perturb-seq datasets, held-out data, and the mouse cell atlas combined with the DisGeNET database demonstrates the improved accuracy and biological interpretability of SCING compared to existing methods. We applied SCING to the entire mouse single cell atlas, human Alzheimer's disease (AD), and mouse AD spatial transcriptomics. SCING GRNs reveal unique disease subnetwork modeling capabilities, have intrinsic capacity to correct for batch effects, retrieve disease relevant genes and pathways, and are informative on spatial specificity of disease pathogenesis.
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Affiliation(s)
- Russell Littman
- Department of Integrative Biology & Physiology, UCLA, Los Angeles, CA, USA
- Bioinformatics Interdepartmental Program, UCLA, Los Angeles, CA, USA
| | - Michael Cheng
- Department of Integrative Biology & Physiology, UCLA, Los Angeles, CA, USA
- Bioinformatics Interdepartmental Program, UCLA, Los Angeles, CA, USA
| | - Ning Wang
- Department of Integrative Biology & Physiology, UCLA, Los Angeles, CA, USA
| | - Chao Peng
- Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Xia Yang
- Department of Integrative Biology & Physiology, UCLA, Los Angeles, CA, USA
- Bioinformatics Interdepartmental Program, UCLA, Los Angeles, CA, USA
- Institute for Quantitative and Computational Biosciences (QCBio), Los Angeles, CA, USA
- Molecular Biology Institute (MBI), Los Angeles, CA, USA
- Brain Research Institute (BRI), Los Angeles, CA, USA
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Elangovan A, Babu HWS, Iyer M, Gopalakrishnan AV, Vellingiri B. Untangle the mystery behind DS-associated AD - Is APP the main protagonist? Ageing Res Rev 2023; 87:101930. [PMID: 37031726 DOI: 10.1016/j.arr.2023.101930] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/11/2023]
Abstract
Amyloid precursor protein profusion in Trisomy 21, also called Down Syndrome (DS), is rooted in the genetic determination of Alzheimer's disease (AD). With the recent development in patient care, the life expectancy of DS patients has gradually increased, leading to the high prospect of AD development, consequently leading to the development of plaques of amyloid proteins and neurofibrillary tangles made of tau by the fourth decade of the patient leading to dementia. The altered gene expression resulted in cellular dysfunction due to impairment of autophagy, mitochondrial and lysosomal dysfunction, and copy number variation controlled by the additional genes in Trisomy 21. The cognitive impairment and mechanistic insights underlying DS-AD conditions have been reviewed in this article. Some recent findings regarding biomarkers and therapeutics of DS-AD conditions were highlighted in this review.
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Affiliation(s)
- Ajay Elangovan
- Stem cell and Regenerative Medicine/ Translational Research, Department of Zoology, School of Basic Sciences, Central University of Punjab, Bathinda 151401, Punjab, India; Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India
| | - Harysh Winster Suresh Babu
- Stem cell and Regenerative Medicine/ Translational Research, Department of Zoology, School of Basic Sciences, Central University of Punjab, Bathinda 151401, Punjab, India; Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India
| | - Mahalaxmi Iyer
- Department of Biotechnology, Karpagam Academy of Higher Education (Deemed to be University), Coimbatore-641021, India
| | | | - Balachandar Vellingiri
- Stem cell and Regenerative Medicine/ Translational Research, Department of Zoology, School of Basic Sciences, Central University of Punjab, Bathinda 151401, Punjab, India; Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India.
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Wang H, Wang LS, Schellenberg G, Lee WP. The role of structural variations in Alzheimer's disease and other neurodegenerative diseases. Front Aging Neurosci 2023; 14:1073905. [PMID: 36846102 PMCID: PMC9944073 DOI: 10.3389/fnagi.2022.1073905] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/31/2022] [Indexed: 02/10/2023] Open
Abstract
Dozens of single nucleotide polymorphisms (SNPs) related to Alzheimer's disease (AD) have been discovered by large scale genome-wide association studies (GWASs). However, only a small portion of the genetic component of AD can be explained by SNPs observed from GWAS. Structural variation (SV) can be a major contributor to the missing heritability of AD; while SV in AD remains largely unexplored as the accurate detection of SVs from the widely used array-based and short-read technology are still far from perfect. Here, we briefly summarized the strengths and weaknesses of available SV detection methods. We reviewed the current landscape of SV analysis in AD and SVs that have been found associated with AD. Particularly, the importance of currently less explored SVs, including insertions, inversions, short tandem repeats, and transposable elements in neurodegenerative diseases were highlighted.
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Affiliation(s)
- Hui Wang
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Li-San Wang
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gerard Schellenberg
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Wan-Ping Lee
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Penn Neurodegeneration Genomics Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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8
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Tsoi PS, Quan MD, Ferreon JC, Ferreon ACM. Aggregation of Disordered Proteins Associated with Neurodegeneration. Int J Mol Sci 2023; 24:3380. [PMID: 36834792 PMCID: PMC9966039 DOI: 10.3390/ijms24043380] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Cellular deposition of protein aggregates, one of the hallmarks of neurodegeneration, disrupts cellular functions and leads to neuronal death. Mutations, posttranslational modifications, and truncations are common molecular underpinnings in the formation of aberrant protein conformations that seed aggregation. The major proteins involved in neurodegeneration include amyloid beta (Aβ) and tau in Alzheimer's disease, α-synuclein in Parkinson's disease, and TAR DNA-binding protein (TDP-43) in amyotrophic lateral sclerosis (ALS). These proteins are described as intrinsically disordered and possess enhanced ability to partition into biomolecular condensates. In this review, we discuss the role of protein misfolding and aggregation in neurodegenerative diseases, specifically highlighting implications of changes to the primary/secondary (mutations, posttranslational modifications, and truncations) and the quaternary/supramolecular (oligomerization and condensation) structural landscapes for the four aforementioned proteins. Understanding these aggregation mechanisms provides insights into neurodegenerative diseases and their common underlying molecular pathology.
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Affiliation(s)
| | | | - Josephine C. Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Allan Chris M. Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX 77030, USA
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9
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Wallon D, Nicolas G. Genetica della malattia di Alzheimer. Neurologia 2022. [DOI: 10.1016/s1634-7072(22)47093-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
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10
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Brain Region-Dependent Alternative Splicing of Alzheimer Disease (AD)-Risk Genes Is Associated With Neuropathological Features in AD. Int Neurourol J 2022; 26:S126-136. [PMID: 36503215 PMCID: PMC9767683 DOI: 10.5213/inj.2244258.129] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 11/20/2022] [Indexed: 11/30/2022] Open
Abstract
PURPOSE Alzheimer disease (AD) is one of the most complex diseases and is characterized by AD-related neuropathological features, including accumulation of amyloid-β plaques and tau neurofibrillary tangles. Dysregulation of alternative splicing (AS) contributes to these features, and there is heterogeneity in features across brain regions between AD patients, leading to different severity and progression rates; however, brain region-specific AS mechanisms still remain unclear. Therefore, we aimed to systemically investigate AS in multiple brain regions of AD patients and how they affect clinical features. METHODS We analyzed RNA sequencing (RNA-Seq) data obtained from brain regions (frontal and temporal) of AD patients. Reads were mapped to the hg19 reference genome using the STAR aligner, and exon skipping (ES) rates were estimated as percent spliced in (PSI) by rMATs. We focused on AD-risk genes discovered by genome-wide association studies, and accordingly evaluated associations between PSI of skipped exons in AD-risk genes and Braak stage and plaque density mean (PM) for each brain region. We also integrated whole-genome sequencing data of the ascertained samples with RNA-Seq data to identify genetic regulators of feature-associated ES. RESULTS We identified 26 and 41 ES associated with Braak stage in frontal and temporal regions, respectively, and 10 and 50 ES associated with PM. Among those, 10 were frontal-specific (CLU and NTRK2), 65 temporal-specific (HIF1A and TRPC4AP), and 26 shared ES (APP) that accompanied functional Gene Ontology terms, including axonogenesis in shared-ES genes. We further identified genetic regulators that account for 44 ES (44% of the total). Finally, we present as a case study the systematic regulation of an ES in APP, which is important in AD pathogenesis. CONCLUSION This study provides new insights into brain region-dependent AS regulation of the architecture of AD-risk genes that contributes to AD pathologies, ultimately allowing identification of a treatment target and region-specific biomarkers for AD.
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Labani M, Afrasiabi A, Beheshti A, Lovell NH, Alinejad-Rokny H. PeakCNV: A multi-feature ranking algorithm-based tool for genome-wide copy number variation-association study. Comput Struct Biotechnol J 2022; 20:4975-4983. [PMID: 36147666 PMCID: PMC9478359 DOI: 10.1016/j.csbj.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/31/2022] [Accepted: 09/01/2022] [Indexed: 11/25/2022] Open
Abstract
Copy Number Variation (CNV) refers to a type of structural genomic alteration in which a segment of chromosome is duplicated or deleted. To date, many CNVs have been identified as causative genetic elements for several diseases and phenotypes. However, performing a CNV-based genome-wide association study is challenging due to inconsistency in length and occurrence of CNVs across different individuals under investigation. One of the most efficient strategies to address this issue is building CNV regions (genomic regions in which CNVs are overlapping - CNVRs). However, this approach is susceptible to a high false positive rate due to overlapping and co-occurring of confounding CNVRs with true positive CNVRs. Here, we develop PeakCNV that differentiates false-positive CNVRs from true positives by calculating a new metric, independence ranking score, (IR-score) via a feature ranking approach. We compared the performance of PeakCNV with other current existing tools by carrying out two case studies one using the CNV genotype data for individuals with prostate cancer (194 cases and 2,392 healthy individuals) and the second one for individuals with neurodevelopmental disorders (19,642 cases and 6,451 healthy individuals). Crucially, our benchmarking analyses on prostate cancer cohort indicated that PeakCNV identifies a fewer risk candidate CNVRs with shorter lengths compared to other tools. Importantly, these CNVRs cover a greater proportion of case over healthy individuals compared to other tools. The accuracy of PeakCNV in identifying relevant candidate CNVRs was reproducible in the case study on neurodevelopmental disorders. Using data from the FANTOM5 expression atlas and the Clinical Genomic Database, we show that the candidate CNVRs identified by PeakCNV for neurodevelopmental disorders overlap with a greater number of genes with the brain-enriched expression, and a greater number of genes that are associated with neurological conditions compared to candidate CNVRs identified by other tools. Taken together, PeakCNV outperformed current existing CNV association study tools by identifying more biologically meaningful CNVRs relevant to the phenotype of interest. PeakCNV is publicly available for the analysis of CNV-associated diseases and is accessible from https://rdrr.io/github/mahdieh1/PeakCNV.
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Affiliation(s)
- Mahdieh Labani
- BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia.,Data Analytics Lab, School of Computing, Macquarie University, Sydney, NSW 2109, Australia
| | - Ali Afrasiabi
- BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Amin Beheshti
- Data Analytics Lab, School of Computing, Macquarie University, Sydney, NSW 2109, Australia
| | - Nigel H Lovell
- The Graduate School of Biomedical Engineering (GSBmE), UNSW Sydney, Sydney, NSW, 2052, Australia.,Tyree Institute of Health Engineering (IHealthE), UNSW Sydney, Sydney, NSW 2052, Australia
| | - Hamid Alinejad-Rokny
- BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia.,UNSW Data Science Hub, The University of New South Wales, Sydney, NSW 2052, Australia.,Health Data Analytics Program, AI-enabled Processes (AIP) Research Centre, Macquarie University, Sydney 2109, Australia
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Tejada Moreno JA, Villegas Lanau A, Madrigal Zapata L, Baena Pineda AY, Velez Hernandez J, Campo Nieto O, Soto Ospina A, Araque Marín P, Rishishwar L, Norris ET, Chande AT, Jordan IK, Bedoya Berrio G. Mutations in SORL1 and MTHFDL1 possibly contribute to the development of Alzheimer's disease in a multigenerational Colombian Family. PLoS One 2022; 17:e0269955. [PMID: 35905044 PMCID: PMC9337667 DOI: 10.1371/journal.pone.0269955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/31/2022] [Indexed: 11/19/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia in the elderly, affecting over 50 million people worldwide in 2020 and this number will triple to 152 million by 2050. Much of the increase will be in developing countries like Colombia. In familial forms, highly penetrant mutations have been identified in three genes, APP, PSEN1, and PSEN2, supporting a role for amyloid-β peptide. In sporadic forms, more than 30 risk genes involved in the lipid metabolism, the immune system, and synaptic functioning mechanisms. We used whole-exome sequencing (WES) to evaluate a family of 97 members, spanning three generations, with a familiar AD, and without mutations in APP, PSEN1, or PSEN2. We sequenced two affected and one unaffected member with the aim of identifying genetic variants that could explain the presence of the disease in the family and the candidate variants were validated in eleven members. We also built a structural model to try to determine the effect on protein function. WES analysis identified two rare variants in SORL1 and MTHFD1L genes segregating in the family with other potential risk variants in APOE, ABCA7, and CHAT, suggesting an oligogenic inheritance. Additionally, the structural 3D models of SORL1 and MTHFD1L variants shows that these variants produce polarity changes that favor hydrophobic interactions, resulting in local structural changes that could affect the protein function and may contribute to the development of the disease in this family.
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Affiliation(s)
| | | | | | | | | | - Omer Campo Nieto
- Molecular Genetics Research Group, University of Antioquia, Medellin, Colombia
| | | | - Pedronel Araque Marín
- Research and Innovation Group in Chemical Formulations, EIA University, Medellin, Colombia
| | - Lavanya Rishishwar
- IHRC-Georgia Tech Applied Bioinformatics Laboratory, Atlanta, Georgia, United States of America
- PanAmerican Bioinformatics Institute, Cali, Valle del Cauca, Colombia
| | - Emily T. Norris
- IHRC-Georgia Tech Applied Bioinformatics Laboratory, Atlanta, Georgia, United States of America
- PanAmerican Bioinformatics Institute, Cali, Valle del Cauca, Colombia
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Aroon T. Chande
- IHRC-Georgia Tech Applied Bioinformatics Laboratory, Atlanta, Georgia, United States of America
- PanAmerican Bioinformatics Institute, Cali, Valle del Cauca, Colombia
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - I. King Jordan
- IHRC-Georgia Tech Applied Bioinformatics Laboratory, Atlanta, Georgia, United States of America
- PanAmerican Bioinformatics Institute, Cali, Valle del Cauca, Colombia
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
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13
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Sato K, Takayama KI, Hashimoto M, Inoue S. Transcriptional and Post-Transcriptional Regulations of Amyloid-β Precursor Protein (APP ) mRNA. FRONTIERS IN AGING 2022; 2:721579. [PMID: 35822056 PMCID: PMC9261399 DOI: 10.3389/fragi.2021.721579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 07/28/2021] [Indexed: 01/01/2023]
Abstract
Alzheimer’s disease (AD) is an age-associated neurodegenerative disorder characterized by progressive impairment of memory, thinking, behavior, and dementia. Based on ample evidence showing neurotoxicity of amyloid-β (Aβ) aggregates in AD, proteolytically derived from amyloid precursor protein (APP), it has been assumed that misfolding of Aβ plays a crucial role in the AD pathogenesis. Additionally, extra copies of the APP gene caused by chromosomal duplication in patients with Down syndrome can promote AD pathogenesis, indicating the pathological involvement of the APP gene dose in AD. Furthermore, increased APP expression due to locus duplication and promoter mutation of APP has been found in familial AD. Given this background, we aimed to summarize the mechanism underlying the upregulation of APP expression levels from a cutting-edge perspective. We first reviewed the literature relevant to this issue, specifically focusing on the transcriptional regulation of APP by transcription factors that bind to the promoter/enhancer regions. APP expression is also regulated by growth factors, cytokines, and hormone, such as androgen. We further evaluated the possible involvement of post-transcriptional regulators of APP in AD pathogenesis, such as RNA splicing factors. Indeed, alternative splicing isoforms of APP are proposed to be involved in the increased production of Aβ. Moreover, non-coding RNAs, including microRNAs, post-transcriptionally regulate the APP expression. Collectively, elucidation of the novel mechanisms underlying the upregulation of APP would lead to the development of clinical diagnosis and treatment of AD.
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Affiliation(s)
- Kaoru Sato
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Ken-Ichi Takayama
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Makoto Hashimoto
- Department of Basic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Satoshi Inoue
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
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14
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Sinnige T. Molecular mechanisms of amyloid formation in living systems. Chem Sci 2022; 13:7080-7097. [PMID: 35799826 PMCID: PMC9214716 DOI: 10.1039/d2sc01278b] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 05/14/2022] [Indexed: 12/28/2022] Open
Abstract
Fibrillar protein aggregation is a hallmark of a variety of human diseases. Examples include the deposition of amyloid-β and tau in Alzheimer's disease, and that of α-synuclein in Parkinson's disease. The molecular mechanisms by which soluble proteins form amyloid fibrils have been extensively studied in the test tube. These investigations have revealed the microscopic steps underlying amyloid formation, and the role of factors such as chaperones that modulate these processes. This perspective explores the question to what extent the mechanisms of amyloid formation elucidated in vitro apply to human disease. The answer is not yet clear, and may differ depending on the protein and the associated disease. Nevertheless, there are striking qualitative similarities between the aggregation behaviour of proteins in vitro and the development of the related diseases. Limited quantitative data obtained in model organisms such as Caenorhabditis elegans support the notion that aggregation mechanisms in vivo can be interpreted using the same biophysical principles established in vitro. These results may however be biased by the high overexpression levels typically used in animal models of protein aggregation diseases. Molecular chaperones have been found to suppress protein aggregation in animal models, but their mechanisms of action have not yet been quantitatively analysed. Several mechanisms are proposed by which the decline of protein quality control with organismal age, but also the intrinsic nature of the aggregation process may contribute to the kinetics of protein aggregation observed in human disease. The molecular mechanisms of amyloid formation have been studied extensively in test tube reactions. This perspective article addresses the question to what extent these mechanisms apply to the complex situation in living cells and organisms.![]()
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Affiliation(s)
- Tessa Sinnige
- Bijvoet Centre for Biomolecular Research, Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
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15
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Farrell C, Mumford P, Wiseman FK. Rodent Modeling of Alzheimer's Disease in Down Syndrome: In vivo and ex vivo Approaches. Front Neurosci 2022; 16:909669. [PMID: 35747206 PMCID: PMC9209729 DOI: 10.3389/fnins.2022.909669] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/16/2022] [Indexed: 12/30/2022] Open
Abstract
There are an estimated 6 million people with Down syndrome (DS) worldwide. In developed countries, the vast majority of these individuals will develop Alzheimer's disease neuropathology characterized by the accumulation of amyloid-β (Aβ) plaques and tau neurofibrillary tangles within the brain, which leads to the early onset of dementia (AD-DS) and reduced life-expectancy. The mean age of onset of clinical dementia is ~55 years and by the age of 80, approaching 100% of individuals with DS will have a dementia diagnosis. DS is caused by trisomy of chromosome 21 (Hsa21) thus an additional copy of a gene(s) on the chromosome must cause the development of AD neuropathology and dementia. Indeed, triplication of the gene APP which encodes the amyloid precursor protein is sufficient and necessary for early onset AD (EOAD), both in people who have and do not have DS. However, triplication of other genes on Hsa21 leads to profound differences in neurodevelopment resulting in intellectual disability, elevated incidence of epilepsy and perturbations to the immune system. This different biology may impact on how AD neuropathology and dementia develops in people who have DS. Indeed, genes on Hsa21 other than APP when in three-copies can modulate AD-pathogenesis in mouse preclinical models. Understanding this biology better is critical to inform drug selection for AD prevention and therapy trials for people who have DS. Here we will review rodent preclinical models of AD-DS and how these can be used for both in vivo and ex vivo (cultured cells and organotypic slice cultures) studies to understand the mechanisms that contribute to the early development of AD in people who have DS and test the utility of treatments to prevent or delay the development of disease.
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16
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Wu CI, Vinton EA, Pearse RV, Heo K, Aylward AJ, Hsieh YC, Bi Y, Adeleye S, Fancher S, Duong DM, Seyfried NT, Schwarz TL, Young-Pearse TL. APP and DYRK1A regulate axonal and synaptic vesicle protein networks and mediate Alzheimer's pathology in trisomy 21 neurons. Mol Psychiatry 2022; 27:1970-1989. [PMID: 35194165 PMCID: PMC9133025 DOI: 10.1038/s41380-022-01454-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 01/18/2022] [Indexed: 11/09/2022]
Abstract
Trisomy 21 (T21) causes Down syndrome and an early-onset form of Alzheimer's disease (AD). Here, we used human induced pluripotent stem cells (hiPSCs) along with CRISPR-Cas9 gene editing to investigate the contribution of chromosome 21 candidate genes to AD-relevant neuronal phenotypes. We utilized a direct neuronal differentiation protocol to bypass neurodevelopmental cell fate phenotypes caused by T21 followed by unbiased proteomics and western blotting to define the proteins dysregulated in T21 postmitotic neurons. We show that normalization of copy number of APP and DYRK1A each rescue elevated tau phosphorylation in T21 neurons, while reductions of RCAN1 and SYNJ1 do not. To determine the T21 alterations relevant to early-onset AD, we identified common pathways altered in familial Alzheimer's disease neurons and determined which of these were rescued by normalization of APP and DYRK1A copy number in T21 neurons. These studies identified disruptions in T21 neurons in both the axonal cytoskeletal network and presynaptic proteins that play critical roles in axonal transport and synaptic vesicle cycling. These alterations in the proteomic profiles have functional consequences: fAD and T21 neurons exhibit dysregulated axonal trafficking and T21 neurons display enhanced synaptic vesicle release. Taken together, our findings provide insights into the initial molecular alterations within neurons that ultimately lead to synaptic loss and axonal degeneration in Down syndrome and early-onset AD.
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Affiliation(s)
- Chun-I Wu
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Elizabeth A Vinton
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Richard V Pearse
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Keunjung Heo
- Harvard Medical School, Boston, MA, USA
- Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Aimee J Aylward
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Yi-Chen Hsieh
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Yan Bi
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Sopefoluwa Adeleye
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Seeley Fancher
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA
| | - Duc M Duong
- Department of Biochemistry, Emory School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory School of Medicine, Atlanta, GA, USA
| | - Nicholas T Seyfried
- Department of Biochemistry, Emory School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory School of Medicine, Atlanta, GA, USA
| | - Thomas L Schwarz
- Harvard Medical School, Boston, MA, USA
- Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Tracy L Young-Pearse
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
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17
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Wang M, Song WM, Ming C, Wang Q, Zhou X, Xu P, Krek A, Yoon Y, Ho L, Orr ME, Yuan GC, Zhang B. Guidelines for bioinformatics of single-cell sequencing data analysis in Alzheimer's disease: review, recommendation, implementation and application. Mol Neurodegener 2022; 17:17. [PMID: 35236372 PMCID: PMC8889402 DOI: 10.1186/s13024-022-00517-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 01/18/2022] [Indexed: 12/13/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia, characterized by progressive cognitive impairment and neurodegeneration. Extensive clinical and genomic studies have revealed biomarkers, risk factors, pathways, and targets of AD in the past decade. However, the exact molecular basis of AD development and progression remains elusive. The emerging single-cell sequencing technology can potentially provide cell-level insights into the disease. Here we systematically review the state-of-the-art bioinformatics approaches to analyze single-cell sequencing data and their applications to AD in 14 major directions, including 1) quality control and normalization, 2) dimension reduction and feature extraction, 3) cell clustering analysis, 4) cell type inference and annotation, 5) differential expression, 6) trajectory inference, 7) copy number variation analysis, 8) integration of single-cell multi-omics, 9) epigenomic analysis, 10) gene network inference, 11) prioritization of cell subpopulations, 12) integrative analysis of human and mouse sc-RNA-seq data, 13) spatial transcriptomics, and 14) comparison of single cell AD mouse model studies and single cell human AD studies. We also address challenges in using human postmortem and mouse tissues and outline future developments in single cell sequencing data analysis. Importantly, we have implemented our recommended workflow for each major analytic direction and applied them to a large single nucleus RNA-sequencing (snRNA-seq) dataset in AD. Key analytic results are reported while the scripts and the data are shared with the research community through GitHub. In summary, this comprehensive review provides insights into various approaches to analyze single cell sequencing data and offers specific guidelines for study design and a variety of analytic directions. The review and the accompanied software tools will serve as a valuable resource for studying cellular and molecular mechanisms of AD, other diseases, or biological systems at the single cell level.
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Affiliation(s)
- Minghui Wang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Won-min Song
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Chen Ming
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Qian Wang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Xianxiao Zhou
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Peng Xu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Azra Krek
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029 USA
| | - Yonejung Yoon
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Lap Ho
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
| | - Miranda E. Orr
- Department of Internal Medicine, Section of Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina USA
- Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest School of Medicine, Winston-Salem, North Carolina USA
| | - Guo-Cheng Yuan
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029 USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Icahn Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Room S8-111, New York, NY 10029 USA
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18
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Kalampokini S, Georgouli D, Patrikiou E, Provatas A, Valotassiou V, Georgoulias P, Spanaki C, Hadjigeorgiou GM, Xiromerisiou G. Τhe Greek Variant in APP Gene: The Phenotypic Spectrum of APP Mutations. Int J Mol Sci 2021; 22:ijms222212355. [PMID: 34830236 PMCID: PMC8622139 DOI: 10.3390/ijms222212355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/11/2021] [Accepted: 11/13/2021] [Indexed: 12/05/2022] Open
Abstract
Mutations in the gene encoding amyloid precursor protein (APP) cause autosomal dominant inherited Alzheimer’s disease (AD). We present a case of a 68-year-old female who presented with epileptic seizures, neuropsychiatric symptoms and progressive memory decline and was found to carry a novel APP variant, c.2062T>G pLeu688Val. A comprehensive literature review of all reported cases of AD due to APP mutations was performed in PubMed and Web of Science databases. We reviewed 98 studies with a total of 385 cases. The mean age of disease onset was 51.3 ± 8.3 (31–80 years). Mutations were most often located in exons 17 (80.8%) and 16 (12.2%). The most common symptoms were dementia, visuospatial symptoms, aphasia, epilepsy and psychiatric symptoms. Mutations in the β-amyloid region, and specifically exon 17, were associated with high pathogenicity and a younger age of disease onset. We describe the second reported APP mutation in the Greek population. APP mutations may act variably on disease expression and their phenotype is heterogeneous.
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Affiliation(s)
- Stefania Kalampokini
- Medical School, University of Cyprus, Nicosia, Cyprus and Department of Neurology, General Hospital of Nicosia, Nicosia 2029, Cyprus;
- Correspondence: ; Tel.: +357-22603911; Fax: +357-22603467
| | - Despoina Georgouli
- Department of Neurology, University Hospital of Larissa, 41334 Larissa, Greece; (D.G.); (A.P.); (G.X.)
| | - Eleni Patrikiou
- Department of Rheumatology and Clinical Immunology, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41223 Larisa, Greece;
| | - Antonios Provatas
- Department of Neurology, University Hospital of Larissa, 41334 Larissa, Greece; (D.G.); (A.P.); (G.X.)
| | - Varvara Valotassiou
- Nuclear Medicine Laboratory, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (V.V.); (P.G.)
| | - Panagiotis Georgoulias
- Nuclear Medicine Laboratory, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (V.V.); (P.G.)
| | - Cleanthe Spanaki
- Department of Neurology, Medical School, University of Crete, 70013 Heraklion, Greece;
| | - Georgios M. Hadjigeorgiou
- Medical School, University of Cyprus, Nicosia, Cyprus and Department of Neurology, General Hospital of Nicosia, Nicosia 2029, Cyprus;
| | - Georgia Xiromerisiou
- Department of Neurology, University Hospital of Larissa, 41334 Larissa, Greece; (D.G.); (A.P.); (G.X.)
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19
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Hampel H, Hardy J, Blennow K, Chen C, Perry G, Kim SH, Villemagne VL, Aisen P, Vendruscolo M, Iwatsubo T, Masters CL, Cho M, Lannfelt L, Cummings JL, Vergallo A. The Amyloid-β Pathway in Alzheimer's Disease. Mol Psychiatry 2021; 26:5481-5503. [PMID: 34456336 PMCID: PMC8758495 DOI: 10.1038/s41380-021-01249-0] [Citation(s) in RCA: 447] [Impact Index Per Article: 149.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 07/19/2021] [Accepted: 07/28/2021] [Indexed: 02/06/2023]
Abstract
Breakthroughs in molecular medicine have positioned the amyloid-β (Aβ) pathway at the center of Alzheimer's disease (AD) pathophysiology. While the detailed molecular mechanisms of the pathway and the spatial-temporal dynamics leading to synaptic failure, neurodegeneration, and clinical onset are still under intense investigation, the established biochemical alterations of the Aβ cycle remain the core biological hallmark of AD and are promising targets for the development of disease-modifying therapies. Here, we systematically review and update the vast state-of-the-art literature of Aβ science with evidence from basic research studies to human genetic and multi-modal biomarker investigations, which supports a crucial role of Aβ pathway dyshomeostasis in AD pathophysiological dynamics. We discuss the evidence highlighting a differentiated interaction of distinct Aβ species with other AD-related biological mechanisms, such as tau-mediated, neuroimmune and inflammatory changes, as well as a neurochemical imbalance. Through the lens of the latest development of multimodal in vivo biomarkers of AD, this cross-disciplinary review examines the compelling hypothesis- and data-driven rationale for Aβ-targeting therapeutic strategies in development for the early treatment of AD.
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Affiliation(s)
- Harald Hampel
- Eisai Inc., Neurology Business Group, Woodcliff Lake, NJ, USA.
| | - John Hardy
- UK Dementia Research Institute at UCL and Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, UK
| | - Kaj Blennow
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
| | - Christopher Chen
- Memory Aging and Cognition Centre, Departments of Pharmacology and Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - George Perry
- Department of Biology and Neurosciences Institute, University of Texas at San Antonio (UTSA), San Antonio, TX, USA
| | - Seung Hyun Kim
- Department of Neurology, College of Medicine, Hanyang University, Seoul, Republic of Korea; Cell Therapy Center, Hanyang University Hospital, Seoul, Republic of Korea
| | - Victor L Villemagne
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Medicine, The University of Melbourne, Melbourne, VIC, Australia
| | - Paul Aisen
- USC Alzheimer's Therapeutic Research Institute, San Diego, CA, USA
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Takeshi Iwatsubo
- Department of Neuropathology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Colin L Masters
- Laureate Professor of Dementia Research, Florey Institute and The University of Melbourne, Parkville, VIC, Australia
| | - Min Cho
- Eisai Inc., Neurology Business Group, Woodcliff Lake, NJ, USA
| | - Lars Lannfelt
- Uppsala University, Department of of Public Health/Geriatrics, Uppsala, Sweden
- BioArctic AB, Stockholm, Sweden
| | - Jeffrey L Cummings
- Chambers-Grundy Center for Transformative Neuroscience, Department of Brain Health, School of Integrated Health Sciences, University of Nevada Las Vegas (UNLV), Las Vegas, NV, USA
| | - Andrea Vergallo
- Eisai Inc., Neurology Business Group, Woodcliff Lake, NJ, USA.
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20
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Kreis A, Desloovere J, Suelves N, Pierrot N, Yerna X, Issa F, Schakman O, Gualdani R, de Clippele M, Tajeddine N, Kienlen-Campard P, Raedt R, Octave JN, Gailly P. Overexpression of wild-type human amyloid precursor protein alters GABAergic transmission. Sci Rep 2021; 11:17600. [PMID: 34475508 PMCID: PMC8413381 DOI: 10.1038/s41598-021-97144-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/13/2021] [Indexed: 02/07/2023] Open
Abstract
The function of the amyloid precursor protein (APP) is not fully understood, but its cleavage product amyloid beta (Aβ) together with neurofibrillary tangles constitute the hallmarks of Alzheimer's disease (AD). Yet, imbalance of excitatory and inhibitory neurotransmission accompanied by loss of synaptic functions, has been reported much earlier and independent of any detectable pathological markers. Recently, soluble APP fragments have been shown to bind to presynaptic GABAB receptors (GABABRs), subsequently decreasing the probability of neurotransmitter release. In this body of work, we were able to show that overexpression of wild-type human APP in mice (hAPPwt) causes early cognitive impairment, neuronal loss, and electrophysiological abnormalities in the absence of amyloid plaques and at very low levels of Aβ. hAPPwt mice exhibited neuronal overexcitation that was evident in EEG and increased long-term potentiation (LTP). Overexpression of hAPPwt did not alter GABAergic/glutamatergic receptor components or GABA production ability. Nonetheless, we detected a decrease of GABA but not glutamate that could be linked to soluble APP fragments, acting on presynaptic GABABRs and subsequently reducing GABA release. By using a specific presynaptic GABABR antagonist, we were able to rescue hyperexcitation in hAPPwt animals. Our results provide evidence that APP plays a crucial role in regulating inhibitory neurotransmission.
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Affiliation(s)
- Anna Kreis
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Jana Desloovere
- grid.5342.00000 0001 2069 7798Faculty of Medicine and Health Sciences, Universiteit Gent, C. Heymanslaan 10, 9000 Gent, Belgium
| | - Nuria Suelves
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Nathalie Pierrot
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Xavier Yerna
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Farah Issa
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Olivier Schakman
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Roberta Gualdani
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Marie de Clippele
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Nicolas Tajeddine
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Pascal Kienlen-Campard
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Robrecht Raedt
- grid.5342.00000 0001 2069 7798Faculty of Medicine and Health Sciences, Universiteit Gent, C. Heymanslaan 10, 9000 Gent, Belgium
| | - Jean-Noël Octave
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Philippe Gailly
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
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21
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Martinez JL, Zammit MD, West NR, Christian BT, Bhattacharyya A. Basal Forebrain Cholinergic Neurons: Linking Down Syndrome and Alzheimer's Disease. Front Aging Neurosci 2021; 13:703876. [PMID: 34322015 PMCID: PMC8311593 DOI: 10.3389/fnagi.2021.703876] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/17/2021] [Indexed: 12/31/2022] Open
Abstract
Down syndrome (DS, trisomy 21) is characterized by intellectual impairment at birth and Alzheimer’s disease (AD) pathology in middle age. As individuals with DS age, their cognitive functions decline as they develop AD pathology. The susceptibility to degeneration of a subset of neurons, known as basal forebrain cholinergic neurons (BFCNs), in DS and AD is a critical link between cognitive impairment and neurodegeneration in both disorders. BFCNs are the primary source of cholinergic innervation to the cerebral cortex and hippocampus, as well as the amygdala. They play a critical role in the processing of information related to cognitive function and are directly engaged in regulating circuits of attention and memory throughout the lifespan. Given the importance of BFCNs in attention and memory, it is not surprising that these neurons contribute to dysfunctional neuronal circuitry in DS and are vulnerable in adults with DS and AD, where their degeneration leads to memory loss and disturbance in language. BFCNs are thus a relevant cell target for therapeutics for both DS and AD but, despite some success, efforts in this area have waned. There are gaps in our knowledge of BFCN vulnerability that preclude our ability to effectively design interventions. Here, we review the role of BFCN function and degeneration in AD and DS and identify under-studied aspects of BFCN biology. The current gaps in BFCN relevant imaging studies, therapeutics, and human models limit our insight into the mechanistic vulnerability of BFCNs in individuals with DS and AD.
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Affiliation(s)
- Jose L Martinez
- Cellular and Molecular Biology Graduate Program, University of Wisconsin, Madison, WI, United States.,Waisman Center, University of Wisconsin, Madison, WI, United States
| | - Matthew D Zammit
- Waisman Center, University of Wisconsin, Madison, WI, United States.,Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
| | - Nicole R West
- Cellular and Molecular Biology Graduate Program, University of Wisconsin, Madison, WI, United States.,Waisman Center, University of Wisconsin, Madison, WI, United States
| | - Bradley T Christian
- Waisman Center, University of Wisconsin, Madison, WI, United States.,Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States.,Department of Psychiatry, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
| | - Anita Bhattacharyya
- Waisman Center, University of Wisconsin, Madison, WI, United States.,Department of Cellular and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
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22
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Ayton S, Bush AI. β-amyloid: The known unknowns. Ageing Res Rev 2021; 65:101212. [PMID: 33188924 DOI: 10.1016/j.arr.2020.101212] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) stands out as a major disease without any form of preventative or disease modifying therapy. This is not for lack of trying. 33 phase 3 clinical trials of drugs targeting amyloid beta (Aβ) have failed to slow cognitive decline in AD. The field is at a cross-roads about whether to continue anti-Aβ therapy or more actively pursue alternative targets. With the burden of this disease to patients, families, and healthcare budgets growing yearly, the need for disease modifying AD therapies has become one of the highest priorities in all of medicine. While pathology, genetic and biochemical data offer a popular narrative for the causative role of Aβ, there are alternative explanations, and dissenting findings that, now more than ever, warrant thorough reanalysis. This review questions the major assumptions about Aβ on which therapies for AD were premised, and invites renewed interrogation into AD pathogenesis.
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Affiliation(s)
- Scott Ayton
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, 3052, Australia.
| | - Ashley I Bush
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, 3052, Australia.
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23
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El Bitar F, Al Sudairy N, Qadi N, Al Rajeh S, Alghamdi F, Al Amari H, Al Dawsari G, Alsubaie S, Al Sudairi M, Abdulaziz S, Al Tassan N. A Comprehensive Analysis of Unique and Recurrent Copy Number Variations in Alzheimer's Disease and its Related Disorders. Curr Alzheimer Res 2020; 17:926-938. [PMID: 33256577 DOI: 10.2174/1567205017666201130111424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 08/20/2020] [Accepted: 10/29/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Copy number variations (CNVs) play an important role in the genetic etiology of various neurological disorders, including Alzheimer's disease (AD). Type 2 diabetes mellitus (T2DM) and major depressive disorder (MDD) were shown to have share mechanisms and signaling pathways with AD. OBJECTIVE We aimed to assess CNVs regions that may harbor genes contributing to AD, T2DM, and MDD in 67 Saudi familial and sporadic AD patients, with no alterations in the known genes of AD and genotyped previously for APOE. METHODS DNA was analyzed using the CytoScan-HD array. Two layers of filtering criteria were applied. All the identified CNVs were checked in the Database of Genomic Variants (DGV). RESULTS A total of 1086 CNVs (565 gains and 521 losses) were identified in our study. We found 73 CNVs harboring genes that may be associated with AD, T2DM or MDD. Nineteen CNVs were novel. Most importantly, 42 CNVs were unique in our studied cohort existing only in one patient. Two large gains on chromosomes 1 and 13 harbored genes implicated in the studied disorders. We identified CNVs in genes that encode proteins involved in the metabolism of amyloid-β peptide (AGRN, APBA2, CR1, CR2, IGF2R, KIAA0125, MBP, RER1, RTN4R, VDR and WISPI) or Tau proteins (CACNAIC, CELF2, DUSP22, HTRA1 and SLC2A14). CONCLUSION The present work provided information on the presence of CNVs related to AD, T2DM, and MDD in Saudi Alzheimer's patients.
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Affiliation(s)
- Fadia El Bitar
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Nourah Al Sudairy
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Najeeb Qadi
- Department of Neurosciences, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | | | - Fatimah Alghamdi
- Institute of Biology and Environmental Research, National Center for Biotechnology, King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia
| | - Hala Al Amari
- Institute of Biology and Environmental Research, National Center for Biotechnology, King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia
| | - Ghadeer Al Dawsari
- Institute of Biology and Environmental Research, National Center for Genomics Technology, King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia
| | - Sahar Alsubaie
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mishael Al Sudairi
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Sara Abdulaziz
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Nada Al Tassan
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
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24
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Implications of germline copy-number variations in psychiatric disorders: review of large-scale genetic studies. J Hum Genet 2020; 66:25-37. [PMID: 32958875 DOI: 10.1038/s10038-020-00838-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/28/2020] [Accepted: 09/01/2020] [Indexed: 02/07/2023]
Abstract
Copy number variants (CNVs), defined as genome sequences of ≥50 bp that differ in copy number from that in a reference genome, are a common form of structural variation. Germline CNVs account for some of the missing heritability that single nucleotide polymorphisms could not account for. Recent technological advances have had a huge impact on CNV research. Microarray technology enables relatively low-cost, high-throughput, genome-wide measurements, and short-read sequencing technology enables the detection of short CNVs that cannot be detected by microarrays. As a result, large-scale genetic studies have been able to identify a variety of common and rare germline CNVs and their associations with diseases. Rare germline CNVs have been reported to be associated with neuropsychiatric disorders. In this review, we focused on germline CNVs and briefly described their functional characteristics, formation mechanisms, detection methods, related databases, and the latest findings. Finally, we introduced recent large-scale genetic studies to assess associations of CNVs with diseases, especially psychiatric disorders, and discussed the use of CNV-based animal models to investigate the molecular and cellular mechanisms underlying these disorders. The development and implementation of improved detection methods, such as long-read single-molecule sequencing, are expected to provide additional insight into the molecular basis of psychiatric disorders and other complex diseases, thus facilitating basic and clinical research on CNVs.
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25
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Kaeser GE, Chun J. Mosaic Somatic Gene Recombination as a Potentially Unifying Hypothesis for Alzheimer's Disease. Front Genet 2020; 11:390. [PMID: 32457796 PMCID: PMC7221065 DOI: 10.3389/fgene.2020.00390] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/27/2020] [Indexed: 12/11/2022] Open
Abstract
The recent identification of somatic gene recombination(SGR) in human neurons affecting the well-known Alzheimer's disease (AD) pathogenic gene, amyloid precursor protein (APP), has implications for the normal and the diseased human brain. The amyloid hypothesis has been the prevailing theory for sporadic AD (SAD) pathogenesis since the discovery of APP gene involvement in familial AD and Down syndrome. Yet, despite enormous scientific and clinical effort, no disease-modifying therapy has emerged. SGR offers a novel mechanism to explain AD pathogenesis and the failures of amyloid-related clinical trials, while maintaining consistency with most aspects of the amyloid hypothesis and additionally supporting possible roles for tau, oxidative stress, inflammation, infection, and prions. SGR retro-inserts novel "genomic complementary DNAs" (gencDNAs) into neuronal genomes and becomes dysregulated in SAD, producing numerous mosaic APP variants, including DNA mutations observed in familial AD. Notably, SGR requires gene transcription, DNA strand-breaks, and reverse transcriptase (RT) activity, all of which may be promoted by well-known AD risk factors and provide a framework for the pursuit of new SGR-based therapeutics. In this perspective, we review evidence for APP SGR in AD pathogenesis and discuss its possible relevance to other AD-related dementias. Further, SGR's requirement for RT activity and the relative absence of AD in aged HIV -infected patients exposed to RT inhibitors suggest that these Food and Drug Administration (FDA)-approved drugs may represent a near-term disease-modifying therapy for AD.
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Affiliation(s)
| | - Jerold Chun
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
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26
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D’Argenio V, Sarnataro D. New Insights into the Molecular Bases of Familial Alzheimer's Disease. J Pers Med 2020; 10:jpm10020026. [PMID: 32325882 PMCID: PMC7354425 DOI: 10.3390/jpm10020026] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/14/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022] Open
Abstract
Like several neurodegenerative disorders, such as Prion and Parkinson diseases, Alzheimer's disease (AD) is characterized by spreading mechanism of aggregated proteins in the brain in a typical "prion-like" manner. Recent genetic studies have identified in four genes associated with inherited AD (amyloid precursor protein-APP, Presenilin-1, Presenilin-2 and Apolipoprotein E), rare mutations which cause dysregulation of APP processing and alterations of folding of the derived amyloid beta peptide (A). Accumulation and aggregation of A in the brain can trigger a series of intracellular events, including hyperphosphorylation of tau protein, leading to the pathological features of AD. However, mutations in these four genes account for a small of the total genetic risk for familial AD (FAD). Genome-wide association studies have recently led to the identification of additional AD candidate genes. Here, we review an update of well-established, highly penetrant FAD-causing genes with correlation to the protein misfolding pathway, and novel emerging candidate FAD genes, as well as inherited risk factors. Knowledge of these genes and of their correlated biochemical cascade will provide several potential targets for treatment of AD and aging-related disorders.
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Affiliation(s)
- Valeria D’Argenio
- CEINGE-Biotecnologie Avanzate scarl, via G. Salvatore 486, 80145 Naples, Italy
- Department of Human Sciences and Quality of Life Promotion, San Raffaele Open University, via di val Cannuta 247, 00166 Rome, Italy
- Correspondence: (V.D.); (D.S.); Tel.: +39-081-3737909 (V.D.); +39-081-7464575 (D.S.)
| | - Daniela Sarnataro
- Department of Molecular Medicine and Medical Biotechnology, Federico II University, via S. Pansini 5, 80131 Naples, Italy
- Correspondence: (V.D.); (D.S.); Tel.: +39-081-3737909 (V.D.); +39-081-7464575 (D.S.)
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27
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Mastromoro G, Gambardella S, Marchionni E, Campopiano R, Traversa A, Di Bonaventura C, Pizzuti A. Unusual Segregation of APP Mutations in Monogenic Alzheimer Disease. NEURODEGENER DIS 2019; 19:96-100. [PMID: 31578030 DOI: 10.1159/000502906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 08/24/2019] [Indexed: 11/19/2022] Open
Abstract
APP gene mutations causing Alzheimer disease (AD) segregate in an autosomal dominant pattern. We report on a 40-year-old woman with a severe cognitive decline starting at 36 years, while her affected relatives presented symptoms onset in the 6th decade. The proband carried an APP missense variant in homozygous state (NM_000484.4: c.2032G>A; NP_000475.1: p.Asp678Asn; rs63750064) and showed a more severe clinical picture than the other AD relatives, as regards the age of onset and the rate of disease progression. This mutation behaves as a semi-dominant trait. The very rare chance of studying APP mutations in the homozygous state demonstrates they are not always dominant and other segregation models are possible.
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Affiliation(s)
- Gioia Mastromoro
- Department of Experimental Medicine, Policlinico Umberto I Hospital, Sapienza University of Rome, Rome, Italy,
| | | | - Enrica Marchionni
- Department of Experimental Medicine, Policlinico Umberto I Hospital, Sapienza University of Rome, Rome, Italy
| | | | - Alice Traversa
- Fondazione IRCCS Casa Sollievo della Sofferenza, Laboratory of Clinical Genomics, San Giovanni Rotondo, Italy
| | - Carlo Di Bonaventura
- Neurology Unit, Department of Neurosciences, Mental Health, Policlinico Umberto I Hospital, Sapienza University of Rome, Rome, Italy
| | - Antonio Pizzuti
- Department of Experimental Medicine, Policlinico Umberto I Hospital, Sapienza University of Rome, Rome, Italy.,Fondazione IRCCS Casa Sollievo della Sofferenza, Laboratory of Clinical Genomics, San Giovanni Rotondo, Italy
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28
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Lee MH, Chun J. Mosaic APP Gene Recombination in Alzheimer's Disease-What's Next? J Exp Neurosci 2019; 13:1179069519849669. [PMID: 31205422 PMCID: PMC6537494 DOI: 10.1177/1179069519849669] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 04/16/2019] [Indexed: 01/05/2023] Open
Abstract
A first example of somatic gene recombination (SGR) within the human brain was recently reported, involving the well-known Alzheimer’s disease (AD)-related gene amyloid precursor protein (APP). SGR was characterized by the creation of APP genomic complementary DNA (gencDNA) sequences that were identified in prefrontal cortical neurons from both normal and sporadic Alzheimer’s disease (SAD) brains. Notably, SGR in SAD appeared to become dysregulated, producing many more numbers and forms of APP gencDNAs, including 11 single-nucleotide variations (SNVs) that are considered pathogenic APP mutations when they occur in families, yet are present mosaically among SAD neurons. APP gene transcription, reverse transcriptase (RT) activity, and DNA strand-breaks were shown to be three key factors required for APP gencDNA production. Many mechanistic details remain to be determined, particularly how APP gencDNAs are involved in AD initiation and progression. The possibility of reducing disease-related SGR through the use of RT inhibitors that are already FDA-approved for HIV and Hepatitis B treatment represents both a testable hypothesis for AD clinical trials and a genuine therapeutic option, where none currently exists, for AD patients.
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Affiliation(s)
- Ming-Hsiang Lee
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Jerold Chun
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
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29
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Kong C, Xie H, Gao Z, Shao M, Li H, Shi R, Cai L, Gao S, Sun T, Li C. Binding between Prion Protein and Aβ Oligomers Contributes to the Pathogenesis of Alzheimer's Disease. Virol Sin 2019; 34:475-488. [PMID: 31093882 DOI: 10.1007/s12250-019-00124-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 03/26/2019] [Indexed: 12/26/2022] Open
Abstract
A plethora of evidence suggests that protein misfolding and aggregation are underlying mechanisms of various neurodegenerative diseases, such as prion diseases and Alzheimer's disease (AD). Like prion diseases, AD has been considered as an infectious disease in the past decades as it shows strain specificity and transmission potential. Although it remains elusive how protein aggregation leads to AD, it is becoming clear that cellular prion protein (PrPC) plays an important role in AD pathogenesis. Here, we briefly reviewed AD pathogenesis and focused on recent progresses how PrPC contributed to AD development. In addition, we proposed a potential mechanism to explain why infectious agents, such as viruses, conduce AD pathogenesis. Microbe infections cause Aβ deposition and upregulation of PrPC, which lead to high affinity binding between Aβ oligomers and PrPC. The interaction between PrPC and Aβ oligomers in turn activates the Fyn signaling cascade, resulting in neuron death in the central nervous system (CNS). Thus, silencing PrPC expression may turn out be an effective treatment for PrPC dependent AD.
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Affiliation(s)
- Chang Kong
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, China.,State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.,Affiliated Cancer Hospital, Institute of Guangzhou Medical University, Guangzhou, 510095, China
| | - Hao Xie
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, China
| | - Zhenxing Gao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Ming Shao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Huan Li
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Run Shi
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Lili Cai
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Shanshan Gao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Taolei Sun
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, China
| | - Chaoyang Li
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China. .,Affiliated Cancer Hospital, Institute of Guangzhou Medical University, Guangzhou, 510095, China.
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30
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Bi C, Bi S, Li B. Processing of Mutant β-Amyloid Precursor Protein and the Clinicopathological Features of Familial Alzheimer's Disease. Aging Dis 2019; 10:383-403. [PMID: 31011484 PMCID: PMC6457050 DOI: 10.14336/ad.2018.0425] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 04/25/2018] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is a complex, multifactorial disease involving many pathological mechanisms. Nonetheless, single pathogenic mutations in amyloid precursor protein (APP) or presenilin 1 or 2 can cause AD with almost all of the clinical and neuropathological features, and therefore, we believe an important mechanism of pathogenesis in AD could be revealed from examining pathogenic APP missense mutations. A comprehensive review of the literature, including clinical, neuropathological, cellular and animal model data, was conducted through PubMed and the databases of Alzforum mutations, HGMD, UniProt, and AD&FTDMDB. Pearson correlation analysis combining the clinical and neuropathological data and aspects of mutant APP processing in cellular models was performed. We find that an increase in Aβ42 has a significant positive correlation with the appearance of neurofibrillary tangles (NFTs) and tends to cause an earlier age of AD onset, while an increase in Aβ40 significantly increases the age at death. The increase in the α-carboxyl terminal fragment (CTF) has a significantly negative correlation with the age of AD onset, and β-CTF has a similar effect without statistical significance. Animal models show that intracellular Aβ is critical for memory defects. Based on these results and the fact that amyloid plaque burden correlates much less well with cognitive impairment than do NFT counts, we propose a "snowball hypothesis": the accumulation of intraneuronal NFTs caused by extracellular Aβ42 and the increase in intraneuronal APP proteolytic products (CTFs and Aβs) could cause cellular organelle stress that leads to neurodegeneration in AD, which then resembles the formation of abnormal protein "snowballs" both inside and outside of neurons.
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Affiliation(s)
- Christopher Bi
- Washington Institute for Health Sciences, Arlington, VA 22203, USA
| | - Stephanie Bi
- Washington Institute for Health Sciences, Arlington, VA 22203, USA
| | - Bin Li
- Washington Institute for Health Sciences, Arlington, VA 22203, USA
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington DC 20057, USA
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31
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Abstract
Virtually all adults with Down syndrome (DS) show the neuropathological changes of Alzheimer disease (AD) by the age of 40 years. This association is partially due to overexpression of amyloid precursor protein, encoded by APP, as a result of the location of this gene on chromosome 21. Amyloid-β accumulates in the brain across the lifespan of people with DS, which provides a unique opportunity to understand the temporal progression of AD and the epigenetic factors that contribute to the age of dementia onset. This age dependency in the development of AD in DS can inform research into the presentation of AD in the general population, in whom a longitudinal perspective of the disease is not often available. Comparison of the risk profiles, biomarker profiles and genetic profiles of adults with DS with those of individuals with AD in the general population can help to determine common and distinct pathways as well as mechanisms underlying increased risk of dementia. This Review evaluates the similarities and differences between the pathological cascades and genetics underpinning DS and AD with the aim of providing a platform for common exploration of these disorders.
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Affiliation(s)
- Ira T Lott
- Department of Pediatrics and Neurology, School of Medicine, University of California, Irvine, CA, USA.
| | - Elizabeth Head
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, USA
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32
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Nikolac Perkovic M, Pivac N. Genetic Markers of Alzheimer's Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1192:27-52. [PMID: 31705489 DOI: 10.1007/978-981-32-9721-0_3] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease is a complex and heterogeneous, severe neurodegenerative disorder and the predominant form of dementia, characterized by cognitive disturbances, behavioral and psychotic symptoms, progressive cognitive decline, disorientation, behavioral changes, and death. Genetic background of Alzheimer's disease differs between early-onset familial Alzheimer's disease, other cases of early-onset Alzheimer's disease, and late-onset Alzheimer's disease. Rare cases of early-onset familial Alzheimer's diseases are caused by high-penetrant mutations in genes coding for amyloid precursor protein, presenilin 1, and presenilin 2. Late-onset Alzheimer's disease is multifactorial and associated with many different genetic risk loci (>20), with the apolipoprotein E ε4 allele being a major genetic risk factor for late-onset Alzheimer's disease. Genetic and genomic studies offer insight into many additional genetic risk loci involved in the genetically complex nature of late-onset Alzheimer's disease. This review highlights the contributions of individual loci to the pathogenesis of Alzheimer's disease and suggests that their exact contribution is still not clear. Therefore, the use of genetic markers of Alzheimer's disease, for monitoring development, time course, treatment response, and prognosis of Alzheimer's disease, is still far away from the clinical application, because the contribution of genetic variations to the relative risk of developing Alzheimer's disease is limited. In the light of prediction and prevention of Alzheimer's disease, a novel approach could be found in the form of additive genetic risk scores, which combine additive effects of numerous susceptibility loci.
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Affiliation(s)
- Matea Nikolac Perkovic
- Division of Molecular Medicine, Rudjer Boskovic Institute, Bijenicka 54, Zagreb, 10000, Croatia
| | - Nela Pivac
- Division of Molecular Medicine, Rudjer Boskovic Institute, Bijenicka 54, Zagreb, 10000, Croatia.
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33
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Rohrback S, Siddoway B, Liu CS, Chun J. Genomic mosaicism in the developing and adult brain. Dev Neurobiol 2018; 78:1026-1048. [PMID: 30027562 PMCID: PMC6214721 DOI: 10.1002/dneu.22626] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 12/18/2022]
Abstract
Since the discovery of DNA, the normal developing and functioning brain has been assumed to be composed of cells with identical genomes, which remains the dominant view even today. However, this pervasive assumption is incorrect, as proven by increasing numbers of reports within the last 20 years that have identified multiple forms of somatically produced genomic mosaicism (GM), wherein brain cells-especially neurons-from a single individual show diverse alterations in DNA, distinct from the germline. Critically, these changes alter the actual DNA nucleotide sequences-in contrast to epigenetic mechanisms-and almost certainly contribute to the remarkably diverse phenotypes of single brain cells, including single-cell transcriptomic profiles. Here, we review the history of GM within the normal brain, including its major forms, initiating mechanisms, and possible functions. GM forms include aneuploidies and aneusomies, smaller copy number variations (CNVs), long interspersed nuclear element type 1 (LINE1) repeat elements, and single nucleotide variations (SNVs), as well as DNA content variation (DCV) that reflects all forms of GM with greatest coverage of large, brain cell populations. In addition, technical considerations are examined, along with relationships among GM forms and multiple brain diseases. GM affecting genes and loci within the brain contrast with current neural discovery approaches that rely on sequencing nonbrain DNA (e.g., genome-wide association studies (GWAS)). Increasing knowledge of neural GM has implications for mechanisms of development, diversity, and function, as well as understanding diseases, particularly considering the overwhelming prevalence of sporadic brain diseases that are unlinked to germline mutations. © 2018 The Authors. Developmental Neurobiology Published by Wiley Periodicals, Inc. Develop Neurobiol, 2018.
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Affiliation(s)
- Suzanne Rohrback
- Biomedical Sciences Graduate Program, School of MedicineUniversity of California San DiegoLa JollaCalifornia92093
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
- Present address:
Illumina, Inc.San DiegoCA 92122USA
| | - Benjamin Siddoway
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
| | - Christine S. Liu
- Biomedical Sciences Graduate Program, School of MedicineUniversity of California San DiegoLa JollaCalifornia92093
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
| | - Jerold Chun
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
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Karch CM, Hernández D, Wang JC, Marsh J, Hewitt AW, Hsu S, Norton J, Levitch D, Donahue T, Sigurdson W, Ghetti B, Farlow M, Chhatwal J, Berman S, Cruchaga C, Morris JC, Bateman RJ, Pébay A, Goate AM. Human fibroblast and stem cell resource from the Dominantly Inherited Alzheimer Network. Alzheimers Res Ther 2018; 10:69. [PMID: 30045758 PMCID: PMC6060509 DOI: 10.1186/s13195-018-0400-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 06/28/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Mutations in amyloid precursor protein (APP), presenilin 1 (PSEN1) and presenilin 2 (PSEN2) cause autosomal dominant forms of Alzheimer disease (ADAD). More than 280 pathogenic mutations have been reported in APP, PSEN1, and PSEN2. However, understanding of the basic biological mechanisms that drive the disease are limited. The Dominantly Inherited Alzheimer Network (DIAN) is an international observational study of APP, PSEN1, and PSEN2 mutation carriers with the goal of determining the sequence of changes in presymptomatic mutation carriers who are destined to develop Alzheimer disease. RESULTS We generated a library of 98 dermal fibroblast lines from 42 ADAD families enrolled in DIAN. We have reprogrammed a subset of the DIAN fibroblast lines into patient-specific induced pluripotent stem cell (iPSC) lines. These cells were thoroughly characterized for pluripotency markers. CONCLUSIONS This library represents a comprehensive resource that can be used for disease modeling and the development of novel therapeutics.
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Affiliation(s)
- Celeste M. Karch
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Damián Hernández
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC Australia
| | - Jen-Chyong Wang
- Department of Neuroscience and Department of Genetics and Genomic Sciences, Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029 USA
| | - Jacob Marsh
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Alex W. Hewitt
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC Australia
- School of Medicine, Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Simon Hsu
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Joanne Norton
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Denise Levitch
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Tamara Donahue
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Wendy Sigurdson
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Bernardino Ghetti
- Department of Pathology and Laboratory Medicine, Indiana University, 635 Barnhill Drive, MS A 142, Indianapolis, IN 46202 USA
| | - Martin Farlow
- Department of Neurology, Indiana University, 635 Barnhill Drive, MS A 142, Indianapolis, IN 46202 USA
| | - Jasmeer Chhatwal
- Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, 149 13th Street, Charlestown, MA 02129 USA
| | - Sarah Berman
- Alzheimer Disease Research Center, University of Pittsburgh School of Medicine, 4-West Montefiore University Hospital, 200 Lothrop Street, Pittsburgh, PA 15213 USA
| | - Carlos Cruchaga
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - John C. Morris
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - Randall J. Bateman
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110 USA
| | - the Dominantly Inherited Alzheimer Network (DIAN)
- Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, 660 South Euclid Avenue, St. Louis, MO 63110 USA
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC Australia
- Department of Neuroscience and Department of Genetics and Genomic Sciences, Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029 USA
- School of Medicine, Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110 USA
- Department of Pathology and Laboratory Medicine, Indiana University, 635 Barnhill Drive, MS A 142, Indianapolis, IN 46202 USA
- Department of Neurology, Indiana University, 635 Barnhill Drive, MS A 142, Indianapolis, IN 46202 USA
- Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, 149 13th Street, Charlestown, MA 02129 USA
- Alzheimer Disease Research Center, University of Pittsburgh School of Medicine, 4-West Montefiore University Hospital, 200 Lothrop Street, Pittsburgh, PA 15213 USA
| | - Alice Pébay
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC Australia
| | - Alison M. Goate
- Department of Neuroscience and Department of Genetics and Genomic Sciences, Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029 USA
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Hunter S, Brayne C. Understanding the roles of mutations in the amyloid precursor protein in Alzheimer disease. Mol Psychiatry 2018; 23:81-93. [PMID: 29112196 DOI: 10.1038/mp.2017.218] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 08/23/2017] [Accepted: 08/24/2017] [Indexed: 12/16/2022]
Abstract
Many models of disease progression in Alzheimer's disease (AD) have been proposed to help guide experimental design and aid the interpretation of results. Models focussing on the genetic evidence include the amyloid cascade (ACH) and presenilin (PSH) hypotheses and the amyloid precursor protein (APP) matrix approach (AMA), of which the ACH has held a dominant position for over two decades. However, the ACH has never been fully accepted and has not yet delivered on its therapeutic promise. We review the ACH, PSH and AMA in relation to levels of APP proteolytic fragments reported from AD-associated mutations in APP. Different APP mutations have diverse effects on the levels of APP proteolytic fragments. This evidence is consistent with at least three disease pathways that can differ between familial and sporadic AD and two pathways associated with cerebral amyloid angiopathy. We cannot fully evaluate the ACH, PSH and AMA in relation to the effects of mutations in APP as the APP proteolytic system has not been investigated systematically. The confounding effects of sequence homology, complexity of competing cleavages and antibody cross reactivities all illustrate limitations in our understanding of the roles these fragments and the APP proteolytic system as a whole in normal aging and disease play. Current experimental design should be refined to generate clearer evidence, addressing both aging and complex disorders with standardised reporting formats. A more flexible theoretical framework capable of accommodating the complexity of the APP proteolytic system is required to integrate available evidence.
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Affiliation(s)
- S Hunter
- Department of Public Health and Primary Care, Institute of Public Health, Forvie Site University of Cambridge, School of Clinical Medicine, Cambridge, UK
| | - C Brayne
- Department of Public Health and Primary Care, Institute of Public Health, Forvie Site University of Cambridge, School of Clinical Medicine, Cambridge, UK
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Clayton KA, Van Enoo AA, Ikezu T. Alzheimer's Disease: The Role of Microglia in Brain Homeostasis and Proteopathy. Front Neurosci 2017; 11:680. [PMID: 29311768 PMCID: PMC5733046 DOI: 10.3389/fnins.2017.00680] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 11/21/2017] [Indexed: 01/15/2023] Open
Abstract
Brain aging is central to late-onset Alzheimer's disease (LOAD), although the mechanisms by which it occurs at protein or cellular levels are not fully understood. Alzheimer's disease is the most common proteopathy and is characterized by two unique pathologies: senile plaques and neurofibrillary tangles, the former accumulating earlier than the latter. Aging alters the proteostasis of amyloid-β peptides and microtubule-associated protein tau, which are regulated in both autonomous and non-autonomous manners. Microglia, the resident phagocytes of the central nervous system, play a major role in the non-autonomous clearance of protein aggregates. Their function is significantly altered by aging and neurodegeneration. This is genetically supported by the association of microglia-specific genes, TREM2 and CD33, and late onset Alzheimer's disease. Here, we propose that the functional characterization of microglia, and their contribution to proteopathy, will lead to a new therapeutic direction in Alzheimer's disease research.
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Affiliation(s)
- Kevin A Clayton
- Department of Pharmacology and Experimental Therapeutics, Medical School, Boston University, Boston, MA, United States
| | - Alicia A Van Enoo
- Department of Pharmacology and Experimental Therapeutics, Medical School, Boston University, Boston, MA, United States
| | - Tsuneya Ikezu
- Department of Pharmacology and Experimental Therapeutics, Medical School, Boston University, Boston, MA, United States.,Department of Neurology, Medical School, Boston University, Boston, MA, United States
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Sekine M, Makino T. Inference of Causative Genes for Alzheimer's Disease Due to Dosage Imbalance. Mol Biol Evol 2017; 34:2396-2407. [PMID: 28666362 DOI: 10.1093/molbev/msx183] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Copy number variations (CNVs) have recently drawn attention as an important genetic factor for diseases, especially common neuropsychiatric disorders including Alzheimer's disease (AD). Because most of the pathogenic CNV regions overlap with multiple genes, it has been challenging to identify the true disease-causing genes amongst them. Notably, a recent study reported that CNV regions containing ohnologs, which are dosage-sensitive genes, are likely to be deleterious. Utilizing the unique feature of ohnologs could be useful for identifying causative genes with pathogenic CNVs, however its effectiveness is still unclear. Although it has been reported that AD is strongly affected by CNVs, most of AD-causing genes with pathogenic CNVs have not been identified yet. Here, we show that dosage-sensitive ohnologs within CNV regions reported in patients with AD are related to the nervous system and are highly expressed in the brain, similar to other known susceptible genes for AD. We found that CNV regions in patients with AD contained dosage-sensitive genes, which are ohnologs not overlapping with control CNV regions, frequently. Furthermore, these dosage-sensitive genes in pathogenic CNV regions had a strong enrichment in the nervous system for mouse knockout phenotype and high expression in the brain similar to the known susceptible genes for AD. Our results demonstrated that selecting dosage-sensitive ohnologs out of multiple genes with pathogenic CNVs is effective in identifying the causative genes for AD. This methodology can be applied to other diseases caused by dosage imbalance and might help to establish the medical diagnosis by analysis of CNVs.
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Affiliation(s)
- Mizuka Sekine
- Department of Biology, Faculty of Science, Tohoku University, Sendai, Japan
| | - Takashi Makino
- Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
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38
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Cuccaro D, De Marco EV, Cittadella R, Cavallaro S. Copy Number Variants in Alzheimer's Disease. J Alzheimers Dis 2017; 55:37-52. [PMID: 27662298 PMCID: PMC5115612 DOI: 10.3233/jad-160469] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2016] [Indexed: 12/18/2022]
Abstract
Alzheimer's disease (AD) is a devastating disease mainly afflicting elderly people, characterized by decreased cognition, loss of memory, and eventually death. Although risk and deterministic genes are known, major genetics research programs are underway to gain further insights into the inheritance of AD. In the last years, in particular, new developments in genome-wide scanning methodologies have enabled the association of a number of previously uncharacterized copy number variants (CNVs, gain or loss of DNA) in AD. Because of the exceedingly large number of studies performed, it has become difficult for geneticists as well as clinicians to systematically follow, evaluate, and interpret the growing number of (sometime conflicting) CNVs implicated in AD. In this review, after a brief introduction of this type of structural variation, and a description of available databases, computational analyses, and technologies involved, we provide a systematic review of all published data showing statistical and scientific significance of pathogenic CNVs and discuss the role they might play in AD.
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Affiliation(s)
- Denis Cuccaro
- Institute of Neurological Sciences, National Research Council, Section of Catania, Italy
| | | | - Rita Cittadella
- Institute of Neurological Sciences, National Research Council, Section of Mangone, Italy
| | - Sebastiano Cavallaro
- Institute of Neurological Sciences, National Research Council, Section of Catania, Italy
- Institute of Neurological Sciences, National Research Council, Section of Mangone, Italy
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Abstract
Down syndrome (also known as trisomy 21) is the model human phenotype for all genomic gain dosage imbalances, including microduplications. The functional genomic exploration of the post-sequencing years of chromosome 21, and the generation of numerous cellular and mouse models, have provided an unprecedented opportunity to decipher the molecular consequences of genome dosage imbalance. Studies of Down syndrome could provide knowledge far beyond the well-known characteristics of intellectual disability and dysmorphic features, as several other important features, including congenital heart defects, early ageing, Alzheimer disease and childhood leukaemia, are also part of the Down syndrome phenotypic spectrum. The elucidation of the molecular mechanisms that cause or modify the risk for different Down syndrome phenotypes could lead to the introduction of previously unimaginable therapeutic options.
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40
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Tosto G, Reitz C. Genomics of Alzheimer's disease: Value of high-throughput genomic technologies to dissect its etiology. Mol Cell Probes 2016; 30:397-403. [PMID: 27618776 DOI: 10.1016/j.mcp.2016.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 09/08/2016] [Accepted: 09/08/2016] [Indexed: 12/31/2022]
Abstract
Late-onset Alzheimer's disease (AD), the most common neurodegenerative disorder in western countries, is clinically defined by progressive worsening in cognitive functions along with function and behavioral impairment. This ultimately results in complete incapacity and death. AD is a clinically and pathologically heterogeneous disease, and this is reflected by the numerous genetic findings that point to several diverse molecular mechanisms and pathways. Linkage, genome-wide association and next-generation sequencing studies have led to the identification of more than 20 novel susceptibility loci for AD. While these observations have significantly increased the knowledge of pathogenic mechanisms and potential therapeutic targets, a large part of the genetic component underlying AD is still unexplained. This review will summarize and discuss the major genetic findings and their potential impact on AD diagnosis and prediction of prognosis.
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Affiliation(s)
- Giuseppe Tosto
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, USA; The Gertrude H. Sergievsky Center, Columbia University, New York, NY, USA; The Department of Neurology, Columbia University, New York, NY, USA
| | - Christiane Reitz
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, USA; The Gertrude H. Sergievsky Center, Columbia University, New York, NY, USA; The Department of Neurology, Columbia University, New York, NY, USA; The Dept. of Epidemiology, Columbia University, New York, NY, USA.
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41
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Relevance of the COPI complex for Alzheimer's disease progression in vivo. Proc Natl Acad Sci U S A 2016; 113:5418-23. [PMID: 27114526 DOI: 10.1073/pnas.1604176113] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Cellular trafficking and recycling machineries belonging to late secretory compartments have been associated with increased Alzheimer's disease (AD) risk. We have shown that coat protein complex I (COPI)-dependent trafficking, an early step in Golgi-to-endoplasmic reticulum retrograde transport, affects amyloid precursor protein subcellular localization, cell-surface expression, as well as its metabolism. We present here a set of experiments demonstrating that, by targeting subunit δ-COP function, the moderation of the COPI-dependent trafficking in vivo leads to a significant decrease in amyloid plaques in the cortex and hippocampus of neurological 17 mice crossed with the 2xTg AD mouse model. Remarkably, an improvement of the memory impairments was also observed. Importantly, human genetic association studies of different AD cohorts led to the identification of 12 SNPs and 24 mutations located in COPI genes linked to an increased AD risk. These findings further demonstrate in vivo the importance of early trafficking steps in AD pathogenesis and open new clinical perspectives.
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42
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Cacace R, Sleegers K, Van Broeckhoven C. Molecular genetics of early-onset Alzheimer's disease revisited. Alzheimers Dement 2016; 12:733-48. [DOI: 10.1016/j.jalz.2016.01.012] [Citation(s) in RCA: 304] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/20/2016] [Accepted: 01/28/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Rita Cacace
- Neurodegenerative Brain Diseases group; Department of Molecular Genetics; VIB; Antwerp Belgium
- Laboratory of Neurogenetics; Institute Born-Bunge, University of Antwerp; Antwerp Belgium
| | - Kristel Sleegers
- Neurodegenerative Brain Diseases group; Department of Molecular Genetics; VIB; Antwerp Belgium
- Laboratory of Neurogenetics; Institute Born-Bunge, University of Antwerp; Antwerp Belgium
| | - Christine Van Broeckhoven
- Neurodegenerative Brain Diseases group; Department of Molecular Genetics; VIB; Antwerp Belgium
- Laboratory of Neurogenetics; Institute Born-Bunge, University of Antwerp; Antwerp Belgium
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43
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Graham LC, Harder JM, Soto I, de Vries WN, John SWM, Howell GR. Chronic consumption of a western diet induces robust glial activation in aging mice and in a mouse model of Alzheimer's disease. Sci Rep 2016; 6:21568. [PMID: 26888450 PMCID: PMC4757836 DOI: 10.1038/srep21568] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 01/22/2016] [Indexed: 02/08/2023] Open
Abstract
Studies have assessed individual components of a western diet, but no study has assessed the long-term, cumulative effects of a western diet on aging and Alzheimer's disease (AD). Therefore, we have formulated the first western-style diet that mimics the fat, carbohydrate, protein, vitamin and mineral levels of western diets. This diet was fed to aging C57BL/6J (B6) mice to identify phenotypes that may increase susceptibility to AD, and to APP/PS1 mice, a mouse model of AD, to determine the effects of the diet in AD. Astrocytosis and microglia/monocyte activation were dramatically increased in response to diet and was further increased in APP/PS1 mice fed the western diet. This increase in glial responses was associated with increased plaque burden in the hippocampus. Interestingly, given recent studies highlighting the importance of TREM2 in microglia/monocytes in AD susceptibility and progression, B6 and APP/PS1 mice fed the western diet showed significant increases TREM2+ microglia/monocytes. Therefore, an increase in TREM2+ microglia/monocytes may underlie the increased risk from a western diet to age-related neurodegenerative diseases such as Alzheimer's disease. This study lays the foundation to fully investigate the impact of a western diet on glial responses in aging and Alzheimer's disease.
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Affiliation(s)
- Leah C. Graham
- The Jackson Laboratory, 600 Main St, Bar Harbor, ME, USA
- Graduate Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, MA 02111, USA
| | | | - Ileana Soto
- The Jackson Laboratory, 600 Main St, Bar Harbor, ME, USA
| | - Wilhelmine N. de Vries
- The Jackson Laboratory, 600 Main St, Bar Harbor, ME, USA
- Howard Hughes Medical Institute, 600 Main St, Bar Harbor, ME, USA
| | - Simon W. M. John
- The Jackson Laboratory, 600 Main St, Bar Harbor, ME, USA
- Graduate Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, MA 02111, USA
- Howard Hughes Medical Institute, 600 Main St, Bar Harbor, ME, USA
- Department of Ophthalmology, Tufts University School of Medicine, Boston, MA, USA
| | - Gareth R. Howell
- The Jackson Laboratory, 600 Main St, Bar Harbor, ME, USA
- Graduate Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, MA 02111, USA
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Eisele YS, Duyckaerts C. Propagation of Aß pathology: hypotheses, discoveries, and yet unresolved questions from experimental and human brain studies. Acta Neuropathol 2016; 131:5-25. [PMID: 26715565 DOI: 10.1007/s00401-015-1516-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 11/29/2015] [Accepted: 11/30/2015] [Indexed: 12/11/2022]
Abstract
In brains of patients with Alzheimer's disease (AD), Aβ peptides accumulate in parenchyma and, almost invariably, also in the vascular walls. Although Aβ aggregation is, by definition, present in AD, its impact is only incompletely understood. It occurs in a stereotypical spatiotemporal distribution within neuronal networks in the course of the disease. This suggests a role for synaptic connections in propagating Aβ pathology, and possibly of axonal transport in an antero- or retrograde way-although, there is also evidence for passive, extracellular diffusion. Striking, in AD, is the conjunction of tau and Aβ pathology. Tau pathology in the cell body of neurons precedes Aβ deposition in their synaptic endings in several circuits such as the entorhino-dentate, cortico-striatal or subiculo-mammillary connections. However, genetic evidence suggests that Aβ accumulation is the first step in AD pathogenesis. To model the complexity and consequences of Aβ aggregation in vivo, various transgenic (tg) rodents have been generated. In rodents tg for the human Aβ precursor protein, focal injections of preformed Aβ aggregates can induce Aβ deposits in the vicinity of the injection site, and over time in more distant regions of the brain. This suggests that Aβ shares with α-synuclein, tau and other proteins the property to misfold and aggregate homotypic molecules. We propose to group those proteins under the term "propagons". Propagons may lack the infectivity of prions. We review findings from neuropathological examinations of human brains in different stages of AD and from studies in rodent models of Aβ aggregation and discuss putative mechanisms underlying the initiation and spread of Aβ pathology.
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Affiliation(s)
- Yvonne S Eisele
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA.
| | - Charles Duyckaerts
- Laboratoire de Neuropathologie Raymond-Escourolle, Hopital de la Pitie-Salpetriere, 47, boulevard de l'Hopital, 75651, Paris Cedex 13, France.
- ICM, equipe Alzheimer-Prion, 47, boulevard de l'Hopital, 750713, Paris, France.
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45
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Choong XY, Tosh JL, Pulford LJ, Fisher EMC. Dissecting Alzheimer disease in Down syndrome using mouse models. Front Behav Neurosci 2015; 9:268. [PMID: 26528151 PMCID: PMC4602094 DOI: 10.3389/fnbeh.2015.00268] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 09/21/2015] [Indexed: 11/13/2022] Open
Abstract
Down syndrome (DS) is a common genetic condition caused by the presence of three copies of chromosome 21 (trisomy 21). This greatly increases the risk of Alzheimer disease (AD), but although virtually all people with DS have AD neuropathology by 40 years of age, not all develop dementia. To dissect the genetic contribution of trisomy 21 to DS phenotypes including those relevant to AD, a range of DS mouse models has been generated which are trisomic for chromosome segments syntenic to human chromosome 21. Here, we consider key characteristics of human AD in DS (AD-DS), and our current state of knowledge on related phenotypes in AD and DS mouse models. We go on to review important features needed in future models of AD-DS, to understand this type of dementia and so highlight pathogenic mechanisms relevant to all populations at risk of AD.
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Affiliation(s)
- Xun Yu Choong
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
| | - Justin L Tosh
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
| | - Laura J Pulford
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
| | - Elizabeth M C Fisher
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; The LonDownS Consortium London, UK
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Wiseman FK, Al-Janabi T, Hardy J, Karmiloff-Smith A, Nizetic D, Tybulewicz VLJ, Fisher EMC, Strydom A. A genetic cause of Alzheimer disease: mechanistic insights from Down syndrome. Nat Rev Neurosci 2015; 16:564-74. [PMID: 26243569 PMCID: PMC4678594 DOI: 10.1038/nrn3983] [Citation(s) in RCA: 337] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Down syndrome, which arises in individuals carrying an extra copy of chromosome 21, is associated with a greatly increased risk of early-onset Alzheimer disease. It is thought that this risk is conferred by the presence of three copies of the gene encoding amyloid precursor protein (APP)--an Alzheimer disease risk factor--although the possession of extra copies of other chromosome 21 genes may also play a part. Further study of the mechanisms underlying the development of Alzheimer disease in people with Down syndrome could provide insights into the mechanisms that cause dementia in the general population.
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Affiliation(s)
- Frances K Wiseman
- Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Tamara Al-Janabi
- Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK
| | - John Hardy
- Department of Molecular Neuroscience, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Annette Karmiloff-Smith
- Centre for Brain and Cognitive Development, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Dean Nizetic
- Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, 11 Mandalay Road, Singapore 308232; and the Blizard Institute, Barts and the London School of Medicine, Queen Mary University of London, 4 Newark Street, London E1 2AT, UK
| | | | - Elizabeth M C Fisher
- Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - André Strydom
- Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK
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47
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Jarmolowicz AI, Chen HY, Panegyres PK. The patterns of inheritance in early-onset dementia: Alzheimer's disease and frontotemporal dementia. Am J Alzheimers Dis Other Demen 2015; 30:299-306. [PMID: 25147204 PMCID: PMC10852564 DOI: 10.1177/1533317514545825] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AIM To investigate the patterns of inheritance and gene mutation status in early-onset dementia (EOD). METHODS Data were collected on 202 consecutive patients presenting to an EOD clinic. Early-onset Alzheimer's disease (EOAD, n = 120) and early-onset frontotemporal dementia (EOFTD, n = 82) were studied. RESULTS The majority of participants, 72.5% with EOAD and 74.4% with EOFTD, did not have a positive family history of dementia. An autosomal dominant pattern of inheritance was observed in 14.2% of patients with EOAD and 13.4% of patients with FTD. Of those with an autosomal dominant pattern of inheritance, 11.8% of EOAD and 45.5% of FTD probands had known pathogenic mutations. Only 1.6% of the total population of EOAD and 7.3% of EOFTD possessed known gene mutations. CONCLUSION Early-onset dementia does not appear to be a strongly inherited autosomal dominant condition. The majority of patients were sporadic. Known mutations were uncommon and do not explain the total autosomal dominant burden.
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Affiliation(s)
- Anna I Jarmolowicz
- Neurodegenerative Disorders Research Pty Ltd, Subiaco, West Perth, Australia
| | - Huei-Yang Chen
- Neurodegenerative Disorders Research Pty Ltd, Subiaco, West Perth, Australia
| | - Peter K Panegyres
- Neurodegenerative Disorders Research Pty Ltd, Subiaco, West Perth, Australia
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Genetic Association Between APP, ADAM10 Gene Polymorphism, and Sporadic Alzheimer’s Disease in the Chinese Population. Neurotox Res 2015; 27:284-91. [DOI: 10.1007/s12640-015-9516-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 01/04/2015] [Accepted: 01/05/2015] [Indexed: 11/25/2022]
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Alzheimer’s Disease Genetics. Curr Behav Neurosci Rep 2014. [DOI: 10.1007/s40473-014-0026-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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50
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Genetic markers for diagnosis and pathogenesis of Alzheimer's disease. Gene 2014; 545:185-93. [DOI: 10.1016/j.gene.2014.05.031] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 04/07/2014] [Accepted: 05/13/2014] [Indexed: 02/06/2023]
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