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Jung M, Jung JS, Pfeifer J, Hartmann C, Ehrhardt T, Abid CL, Kintzel J, Puls A, Navarrete Santos A, Hollemann T, Riemann D, Rujescu D. Neuronal Stem Cells from Late-Onset Alzheimer Patients Show Altered Regulation of Sirtuin 1 Depending on Apolipoprotein E Indicating Disturbed Stem Cell Plasticity. Mol Neurobiol 2024; 61:1562-1579. [PMID: 37728850 PMCID: PMC10896791 DOI: 10.1007/s12035-023-03633-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 08/31/2023] [Indexed: 09/21/2023]
Abstract
Late-onset Alzheimer's disease (AD) is a complex multifactorial disease. The greatest known risk factor for late-onset AD is the E4 allele of the apolipoprotein E (APOE), while increasing age is the greatest known non-genetic risk factor. The cell type-specific functions of neural stem cells (NSCs), in particular their stem cell plasticity, remain poorly explored in the context of AD pathology. Here, we describe a new model that employs late-onset AD patient-derived induced pluripotent stem cells (iPSCs) to generate NSCs and to examine the role played by APOE4 in the expression of aging markers such as sirtuin 1 (SIRT1) in comparison to healthy subjects carrying APOE3. The effect of aging was investigated by using iPSC-derived NSCs from old age subjects as healthy matched controls. Transcript and protein analysis revealed that genes were expressed differently in NSCs from late-onset AD patients, e.g., exhibiting reduced autophagy-related protein 7 (ATG7), phosphatase and tensin homolog (PTEN), and fibroblast growth factor 2 (FGF2). Since SIRT1 expression differed between APOE3 and APOE4 NSCs, the suppression of APOE function in NSCs also repressed the expression of SIRT1. However, the forced expression of APOE3 by plasmids did not recover differently expressed genes. The altered aging markers indicate decreased plasticity of NSCs. Our study provides a suitable in vitro model to investigate changes in human NSCs associated with aging, APOE4, and late-onset AD.
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Affiliation(s)
- Matthias Jung
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany.
| | - Juliane-Susanne Jung
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Grosse Steinstrasse 52, 06118, Halle (Saale), Germany
| | - Jenny Pfeifer
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Carla Hartmann
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Toni Ehrhardt
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Chaudhry Luqman Abid
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Jenny Kintzel
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Anne Puls
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Anne Navarrete Santos
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Grosse Steinstrasse 52, 06118, Halle (Saale), Germany
| | - Thomas Hollemann
- Institute of Physiological Chemistry (IPC), Faculty of Medicine, Martin Luther University Halle-Wittenberg, Hollystrasse 1, 06114, Halle (Saale), Germany
| | - Dagmar Riemann
- Department Medical Immunology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Magdeburger Strasse 2, 06112, Halle (Saale), Germany
| | - Dan Rujescu
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
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Gottschalk WK, Mahon S, Hodgson D, Barrera J, Hill D, Wei A, Kumar M, Dai K, Anderson L, Mihovilovic M, Lutz MW, Chiba-Falek O. The APOE-TOMM40 Humanized Mouse Model: Characterization of Age, Sex, and PolyT Variant Effects on Gene Expression. J Alzheimers Dis 2023; 94:1563-1576. [PMID: 37458041 PMCID: PMC10733864 DOI: 10.3233/jad-230451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
BACKGROUND The human chromosome 19q13.32 is a gene rich region and has been associated with multiple phenotypes, including late onset Alzheimer's disease (LOAD) and other age-related conditions. OBJECTIVE Here we developed the first humanized mouse model that contains the entire TOMM40 and APOE genes with all intronic and intergenic sequences including the upstream and downstream regions. Thus, the mouse model carries the human TOMM40 and APOE genes and their intact regulatory sequences. METHODS We generated the APOE-TOMM40 humanized mouse model in which the entire mouse region was replaced with the human (h)APOE-TOMM40 loci including their upstream and downstream flanking regulatory sequences using recombineering technologies. We then measured the expression of the human TOMM40 and APOE genes in the mice brain, liver, and spleen tissues using TaqMan based mRNA expression assays. RESULTS We investigated the effects of the '523' polyT genotype (S/S or VL/VL), sex, and age on the human TOMM40- and APOE-mRNAs expression levels using our new humanized mouse model. The analysis revealed tissue specific and shared effects of the '523' polyT genotype, sex, and age on the regulation of the human TOMM40 and APOE genes. Noteworthy, the regulatory effect of the '523' polyT genotype was observed for all studied organs. CONCLUSION The model offers new opportunities for basic science, translational, and preclinical drug discovery studies focused on the APOE genomic region in relation to LOAD and other conditions in adulthood.
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Affiliation(s)
- William K. Gottschalk
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Scott Mahon
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Dellila Hodgson
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
| | - Julio Barrera
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
| | - Delaney Hill
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
| | - Angela Wei
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
| | - Manish Kumar
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
| | - Kathy Dai
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
| | - Lauren Anderson
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Mirta Mihovilovic
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Michael W. Lutz
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Ornit Chiba-Falek
- Division of Translational Brain Sciences, Department of Neurology, Duke University Medical Center, Durham, NC, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA
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Zou H, Luo S, Liu H, Lutz MW, Bennett DA, Plassman BL, Welsh-Bohmer KA. Genotypic Effects of the TOMM40'523 Variant and APOE on Longitudinal Cognitive Change over 4 Years: The TOMMORROW Study. J Prev Alzheimers Dis 2023; 10:886-894. [PMID: 37874111 PMCID: PMC10734664 DOI: 10.14283/jpad.2023.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
BACKGROUND The 523 poly-T length polymorphism (rs10524523) in TOMM40 has been reported to influence longitudinal cognitive test performance within APOE ε3/3 carriers. The results from prior studies are inconsistent. It is also unclear whether specific APOE and TOMM40 genotypes contribute to heterogeneity in longitudinal cognitive performance during the preclinical stages of AD. OBJECTIVES To determine the effects of these genes on longitudinal cognitive change in early preclinical stages of AD, we used the clinical trial data from the recently concluded TOMMORROW study to examine the effects of APOE and TOMM40 genotypes on neuropsychological test performance. DESIGN A phase 3, double-blind, placebo-controlled, randomized clinical trial. SETTING Academic affiliated and private research clinics in Australia, Germany, Switzerland, the UK, and the USA. PARTICIPANTS Cognitively normal older adults aged 65 to 83. INTERVENTION Pioglitazone tablet. MEASUREMENTS Participants from the TOMMORROW trial were stratified based on APOE genotype (APOE ε3/3, APOE ε3/4, APOE ε4/4). APOE ε3/3 carriers were further stratified by TOMM40'523 genotype. The final analysis dataset consists of 1,330 APOE ε3/3 carriers and 7,001 visits. Linear mixed models were used to compare the rates of decline in cognition across APOE groups and the APOE ε3/3 carriers with different TOMM40'523 genotypes. RESULTS APOE ε3/4 and APOE ε4/4 genotypes compared with the APOE ε3/3 genotype were associated with worse performance on measures of global cognition, episodic memory, and expressive language. Further, over the four years of observation, the APOE ε3/3 carriers with the TOMM40'523-S/S genotype showed better global cognition and accelerated rates of cognitive decline on tests of global cognition, executive function, and attentional processing compared to APOE ε3/3 carriers with TOMM40'523-S/VL and VL/VL genotypes and compared to the APOE ε3/4 and APOE ε4/4 carriers. CONCLUSIONS We suggest that both APOE and TOMM40 genotypes may independently contribute to cognitive heterogeneity in the pre-MCI stages of AD. Controlling for this genetic variability will be important in clinical trials designed to slow the rate of cognitive decline and/or prevent symptom onset in preclinical AD.
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Affiliation(s)
- H Zou
- Sheng Luo, PhD, Dept of Biostatistics and Bioinformatics, 2424 Erwin Rd, Suite 11082, Durham, NC, USA, 27705, Tel: 919-668-8038, Fax: 919-668-7059,
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Genetic Variants and Haplotypes of TOMM40, APOE, and APOC1 are Related to the Age of Onset of Late-onset Alzheimer Disease in a Colombian Population. Alzheimer Dis Assoc Disord 2022; 36:29-35. [PMID: 35149606 DOI: 10.1097/wad.0000000000000477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 08/04/2021] [Indexed: 11/01/2022]
Abstract
BACKGROUND The Apolipoprotein E (APOE) gene is the main risk factor for late-onset Alzheimer disease (LOAD). Genetic variants and haplotypes in regions near the APOE locus may be associated with LOAD in the Colombian population. OBJECTIVE We evaluated frequencies and risk of genetic variants and haplotypes in APOE, TOMM40, and APOC1 promoters, also in putative regulatory enhancer elements (TOMM40 IVS2-4 and TOMM40 IVS6), and in cis-regulatory elements (ME1 and BCR). MATERIALS AND METHODS Our case-control association study was carried out in 50 patients with LOAD and 50 controls. We determined frequencies and odd ratios for genetic variants and haplotypes. RESULTS We found a significant association between LOAD and genetic variants at the TOMM40 promoter, at TOMM40 IVS2-4 and TOMM40 IVS6 regulatory enhancer elements, and at the APOC1 promoter. Particularly, variants of Poly-T and APOC1 promoter could anticipate the age of onset of LOAD in our population. We identified three risk haplotypes in TOMM40 (ACGGAG, ACGGGG, and ATAGGC) related to LOAD's age of onset. We also found other risk or protection haplotypes at the TOMM40 and APOE promoters, at TOMM40 IVS2-4, TOMM40 IVS6 regulatory enhancer elements, and at ME1. CONCLUSION Genetic variants and haplotypes near the APOE locus are related to LOAD risk and accelerated onset of LOAD in the Colombian population.
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Co-Expression Network Analysis of Micro-RNAs and Proteins in the Alzheimer's Brain: A Systematic Review of Studies in the Last 10 Years. Cells 2021; 10:cells10123479. [PMID: 34943987 PMCID: PMC8699941 DOI: 10.3390/cells10123479] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/04/2021] [Accepted: 12/07/2021] [Indexed: 12/16/2022] Open
Abstract
MicroRNAs (miRNAs) are small non-coding nucleic acids that can regulate post-transcriptional gene expression by binding to complementary sequences of target mRNA. Evidence showed that dysregulated miRNA expression may be associated with neurological conditions such as Alzheimer’s disease (AD). In this study, we combined the results of two independent systematic reviews aiming to unveil the co-expression network of miRNAs and proteins in brain tissues of AD patients. Twenty-eight studies including a total of 113 differentially expressed miRNAs (53 of them validated by qRT-PCR), and 26 studies including a total of 196 proteins differentially expressed in AD brains compared to healthy age matched controls were selected. Pathways analyses were performed on the results of the two reviews and 39 common pathways were identified. A further bioinformatic analysis was performed to match miRNA and protein targets with an inverse relation. This revealed 249 inverse relationships in 28 common pathways, representing new potential targets for therapeutic intervention. A meta-analysis, whenever possible, revealed miR-132-3p and miR-16 as consistently downregulated in late-stage AD across the literature. While no inverse relationships between miR-132-3p and proteins were found, miR-16′s inverse relationship with CLOCK proteins in the circadian rhythm pathway is discussed and therapeutic targets are proposed. The most significant miRNA dysregulated pathway highlighted in this review was the hippo signaling pathway with p = 1.66 × 10−9. Our study has revealed new mechanisms for AD pathogenesis and this is discussed along with opportunities to develop novel miRNA-based drugs to target these pathways.
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Kloske CM, Dugan AJ, Weekman EM, Winder Z, Patel E, Nelson PT, Fardo DW, Wilcock DM. Inflammatory Pathways Are Impaired in Alzheimer Disease and Differentially Associated With Apolipoprotein E Status. J Neuropathol Exp Neurol 2021; 80:922-932. [PMID: 34486652 PMCID: PMC8557334 DOI: 10.1093/jnen/nlab085] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Alzheimer disease (AD) is a neurodegenerative disease characterized by a cognitive decline leading to dementia. The most impactful genetic risk factor is apolipoprotein E (APOE). APOE-ε4 significantly increases AD risk, APOE-ε3 is the most common gene variant, and APOE-ε2 protects against AD. However, the underlying mechanisms of APOE-ε4 on AD risk remains unclear, with APOE-ε4 impacting many pathways. We investigated how the APOE isoforms associated with the neuroinflammatory state of the brain with and without AD pathology. Frozen brain tissue from the superior and middle temporal gyrus was analyzed from APOE-ε3/3 (n = 9) or APOE-ε4/4 (n = 10) participants with AD pathology and APOE-ε3/3 (n = 9) participants without AD pathology. We determined transcript levels of 757 inflammatory related genes using the NanoString Human Neuroinflammation Panel. We found significant pathways impaired in APOE-ε4/4-AD individuals compared to APOE-ε3/3-AD. Of interest, expression of genes related to microglial activation (SALL1), motility (FSCN1), epigenetics (DNMT1), and others showed altered expression. Additionally, we performed immunohistochemistry of P2RY12 to confirm reduced microglial activation. Our results suggest APOE-ε3 responds to AD pathology while potentially having a harmful long-term inflammatory response, while APOE-ε4 shows a weakened response to pathology. Overall, APOE isoforms appear to modulate the brain immune response to AD-type pathology.
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Affiliation(s)
- Courtney M Kloske
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Adam J Dugan
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Erica M Weekman
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Zachary Winder
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Ela Patel
- Department of Pathology and Laboratory Medicine, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Peter T Nelson
- Department of Pathology and Laboratory Medicine, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - David W Fardo
- Department of Biostatics, Sanders-Brown Center on Aging, College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Donna M Wilcock
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
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TOMM40 RNA Transcription in Alzheimer's Disease Brain and Its Implication in Mitochondrial Dysfunction. Genes (Basel) 2021; 12:genes12060871. [PMID: 34204109 PMCID: PMC8226536 DOI: 10.3390/genes12060871] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 11/24/2022] Open
Abstract
Increasing evidence suggests that the Translocase of Outer Mitochondria Membrane 40 (TOMM40) gene may contribute to the risk of Alzheimer’s disease (AD). Currently, there is no consensus as to whether TOMM40 expression is up- or down-regulated in AD brains, hindering a clear interpretation of TOMM40’s role in this disease. The aim of this study was to determine if TOMM40 RNA levels differ between AD and control brains. We applied RT-qPCR to study TOMM40 transcription in human postmortem brain (PMB) and assessed associations of these RNA levels with genetic variants in APOE and TOMM40. We also compared TOMM40 RNA levels with mitochondrial functions in human cell lines. Initially, we found that the human genome carries multiple TOMM40 pseudogenes capable of producing highly homologous RNAs that can obscure precise TOMM40 RNA measurements. To circumvent this obstacle, we developed a novel RNA expression assay targeting the primary transcript of TOMM40. Using this assay, we showed that TOMM40 RNA was upregulated in AD PMB. Additionally, elevated TOMM40 RNA levels were associated with decreases in mitochondrial DNA copy number and mitochondrial membrane potential in oxidative stress-challenged cells. Overall, differential transcription of TOMM40 RNA in the brain is associated with AD and could be an indicator of mitochondrial dysfunction.
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8
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Zhou X, Fu AK, Ip NY. APOE signaling in neurodegenerative diseases: an integrative approach targeting APOE coding and noncoding variants for disease intervention. Curr Opin Neurobiol 2021; 69:58-67. [PMID: 33647674 DOI: 10.1016/j.conb.2021.02.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/05/2021] [Accepted: 02/05/2021] [Indexed: 10/22/2022]
Abstract
APOE (apolipoprotein E) is a key regulator of lipid metabolism and a leading genetic risk factor for Alzheimer's disease. While APOE participates in multiple biological pathways, its roles in diseases are largely due to the mutant protein encoded by APOE-ε4. However, emerging evidence suggests that some noncoding Alzheimer's disease risk variants residing in APOE and its nearby regions exert APOE-ε4-independent risks and modify APOE gene expression. Moreover, intervention strategies targeting APOE are being explored. In this review, we summarize the literature on the genetic risks and roles of APOE in biological systems. Moreover, we propose an integrative approach to evaluate disease risk and tailor interventions to aid research on APOE-associated diseases.
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Affiliation(s)
- Xiaopu Zhou
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, 518057 Shenzhen, Guangdong, China
| | - Amy Ky Fu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, 518057 Shenzhen, Guangdong, China
| | - Nancy Y Ip
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, 518057 Shenzhen, Guangdong, China.
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9
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Afghah Z, Chen X, Geiger JD. Role of endolysosomes and inter-organellar signaling in brain disease. Neurobiol Dis 2020; 134:104670. [PMID: 31707116 PMCID: PMC7184921 DOI: 10.1016/j.nbd.2019.104670] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 10/14/2019] [Accepted: 11/05/2019] [Indexed: 12/29/2022] Open
Abstract
Endosomes and lysosomes (endolysosomes) are membrane bounded organelles that play a key role in cell survival and cell death. These acidic intracellular organelles are the principal sites for intracellular hydrolytic activity required for the maintenance of cellular homeostasis. Endolysosomes are involved in the degradation of plasma membrane components, extracellular macromolecules as well as intracellular macromolecules and cellular fragments. Understanding the physiological significance and pathological relevance of endolysosomes is now complicated by relatively recent findings of physical and functional interactions between endolysosomes with other intracellular organelles including endoplasmic reticulum, mitochondria, plasma membranes, and peroxisomes. Indeed, evidence clearly indicates that endolysosome dysfunction and inter-organellar signaling occurs in different neurodegenerative diseases including Alzheimer's disease (AD), HIV-1 associated neurocognitive disease (HAND), Parkinson's disease (PD) as well as various forms of brain cancer such as glioblastoma multiforme (GBM). These findings open new areas of cell biology research focusing on understanding the physiological actions and pathophysiological consequences of inter-organellar communication. Here, we will review findings of others and us that endolysosome de-acidification and dysfunction coupled with impaired inter-organellar signaling is involved in the pathogenesis of AD, HAND, PD, and GBM. A more comprehensive appreciation of cell biology and inter-organellar signaling could lead to the development of new drugs to prevent or cure these diseases.
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Affiliation(s)
- Zahra Afghah
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201, United States of America
| | - Xuesong Chen
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201, United States of America
| | - Jonathan D Geiger
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201, United States of America.
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Lutz MW, Casanova R, Saldana S, Kuchibhatla M, Plassman BL, Hayden KM. Analysis of pleiotropic genetic effects on cognitive impairment, systemic inflammation, and plasma lipids in the Health and Retirement Study. Neurobiol Aging 2019; 80:173-186. [PMID: 31201950 DOI: 10.1016/j.neurobiolaging.2018.10.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 08/11/2018] [Accepted: 10/29/2018] [Indexed: 01/31/2023]
Abstract
Variants associated with modulation of c-reactive protein (CRP) and plasma lipids have been investigated for polygenic overlap with Alzheimer's disease risk variants. We examined pleiotropic genetic effects on cognitive impairment conditioned on genetic variants (SNPs) associated with systemic inflammation as measured by CRP and with plasma lipids using data from the Health and Retirement Study. SNP enrichment was observed for cognitive impairment conditioned on the secondary phenotypes of plasma CRP and lipids. Fold enrichment of 100%-800% was observed for increasingly stringent p-value thresholds for SNPs associated with cognitive impairment conditional on plasma CRP, 80%-800% for low-density lipoprotein, and 80%-600% for total cholesterol. Significant associations (false discovery rate Q ≤ 0.05) between cognitive impairment, conditional with either CRP, low-density lipoprotein, or total cholesterol, were found for the locus on chromosome 19 that contains the APOE, TOMM40, APOC1, and PVRL2 genes. Relative numbers of significant SNPs in each of the genes differed by the conditional associations with the secondary phenotypes. Biological interpretation of both the genetic pleiotropy results and the individual genome-wide association results showed that the variants and proximal genes identified are involved in multiple pathological processes including cholesterol metabolism, inflammation, and mitochondrial transport. These findings are potentially important for Alzheimer's disease risk prediction and development of novel therapeutic approaches.
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Affiliation(s)
- Michael W Lutz
- Department of Neurology, Duke University School of Medicine, Durham, NC, USA.
| | - Ramon Casanova
- Department of Biostatistics and Data Science, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Santiago Saldana
- Department of Biostatistics and Data Science, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Maragatha Kuchibhatla
- Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Winston-Salem, NC, USA
| | - Brenda L Plassman
- Department of Neurology, Duke University School of Medicine, Durham, NC, USA
| | - Kathleen M Hayden
- Department of Social Sciences and Health Policy, Wake Forest School of Medicine, Winston-Salem, NC, USA
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11
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Abstract
Apolipoprotein E (apoE) is a 34-kDa glycoprotein that is secreted from many cells throughout the body. ApoE is best known for its role in lipoprotein metabolism. Recent studies underline the association of circulating lipoprotein-associated apoE levels and the development for cardiovascular disease (CVD). Besides its well-established role in pathology of CVD, it is also implicated in neurodegenerative diseases and recent new data on adipose-produced apoE point to a novel metabolic role for apoE in obesity. The regulation of apoE production and secretion is remarkably cell and tissue specific. Here, we summarize recent insights into the differential regulation apoE production and secretion by hepatocytes, monocytes/macrophages, adipocytes, and the central nervous system and relevant variations in apoE biochemistry and function.
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Affiliation(s)
- Maaike Kockx
- Concord Repatriation General Hospital, ANZAC Research Institute, Sydney, Australia
- Sydney Medical School, University of Sydney, Sydney, Australia
| | - Mathew Traini
- Concord Repatriation General Hospital, ANZAC Research Institute, Sydney, Australia
- Sydney Medical School, University of Sydney, Sydney, Australia
| | - Leonard Kritharides
- Concord Repatriation General Hospital, ANZAC Research Institute, Sydney, Australia.
- Sydney Medical School, University of Sydney, Sydney, Australia.
- Department of Cardiology, Concord Repatriation General Hospital, Concord, NSW, 2139, Australia.
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Shao Y, Shaw M, Todd K, Khrestian M, D'Aleo G, Barnard PJ, Zahratka J, Pillai J, Yu CE, Keene CD, Leverenz JB, Bekris LM. DNA methylation of TOMM40-APOE-APOC2 in Alzheimer's disease. J Hum Genet 2018; 63:459-471. [PMID: 29371683 DOI: 10.1038/s10038-017-0393-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 12/12/2022]
Abstract
The apolipoprotein E (APOE) ε4 allele is the major genetic risk factor for Alzheimer's disease (AD). Multiple regulatory elements, spanning the extended TOMM40-APOE-APOC2 region, regulate gene expression at this locus. Regulatory element DNA methylation changes occur under different environmental conditions, such as disease. Our group and others have described an APOE CpG island as hypomethylated in AD, compared to cognitively normal controls. However, little is known about methylation of the larger TOMM40-APOE-APOC2 region. The hypothesis of this investigation was that regulatory element methylation levels of the larger TOMM40-APOE-APOC2 region are associated with AD. The aim was to determine whether DNA methylation of the TOMM40-APOE-APOC2 region differs in AD compared to cognitively normal controls in post-mortem brain and peripheral blood. DNA was extracted from human brain (n = 12) and peripheral blood (n = 67). A methylation array was used for this analysis. Percent methylation within the TOMM40-APOE-APOC2 region was evaluated for differences according to tissue type, disease state, AD-related biomarkers, and gene expression. Results from this exploratory analysis suggest that regulatory element methylation levels within the larger TOMM40-APOE-APOC2 gene region correlate with AD-related biomarkers and TOMM40 or APOE gene expression in AD.
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Affiliation(s)
- Yvonne Shao
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - McKenzie Shaw
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Kaitlin Todd
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Maria Khrestian
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Giana D'Aleo
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - P John Barnard
- Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA
| | - Jeff Zahratka
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Jagan Pillai
- Lou Ruvo Center for Brain Health, Cleveland Clinic, Cleveland, OH, USA
| | - Chang-En Yu
- Department of Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - C Dirk Keene
- Department of Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - James B Leverenz
- Lou Ruvo Center for Brain Health, Cleveland Clinic, Cleveland, OH, USA
| | - Lynn M Bekris
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA.
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Association Analysis of Polymorphisms in TOMM40, CR1, PVRL2, SORL1, PICALM, and 14q32.13 Regions in Colombian Alzheimer Disease Patients. Alzheimer Dis Assoc Disord 2017; 30:305-309. [PMID: 27023435 DOI: 10.1097/wad.0000000000000142] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
OBJECTIVE We evaluated the association of several single-nucleotide polymorphisms in different genes including APOE, TOMM40, CR1, PVRL2, SORL1, PICALM, and GWA_14q32.13 in a Colombian sample of Late-Onset Alzheimer disease (LOAD) patients. METHODS A case-control study was conducted in 362 individuals (181 LOADs and 181 controls) to determine the association of single-nucleotide polymorphisms in APOE (e2, e3, and e4), TOMM40 (rs2075650), CR1 (rs665640), PVRL2 (rs6859), SORL1 (rs11218304), PICALM (rs3851179), and GWA_14q32.13 (rs11622883) with LOAD in a sample from Colombia. RESULTS We were able to confirm the previously reported association of the APOE4 allele with AD. In addition, we report a new significant association with rs2075650 of TOMM40 for LOAD in our sample. We did not detect any significant interaction between TOMM40 and APOE4 carriers (heterozygous or homozygous) for disease risk development. However, Kaplan-Meier survival analyses suggest that AD patients with TOMM40 allele rs2075650-G have an average age of disease onset of 6 years earlier compared with carriers of the A allele. In addition, the age of disease onset is earlier if APOE4/4 is present. CONCLUSION Our findings suggest that rs2075650 of TOMM40 could be involved in earlier presentation of LOAD in the Colombian population.
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Mitochondria, Cybrids, Aging, and Alzheimer's Disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 146:259-302. [PMID: 28253988 DOI: 10.1016/bs.pmbts.2016.12.017] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mitochondrial and bioenergetic function change with advancing age and may drive aging phenotypes. Mitochondrial and bioenergetic changes are also documented in various age-related neurodegenerative diseases, including Alzheimer's disease (AD). In some instances AD mitochondrial and bioenergetic changes are reminiscent of those observed with advancing age but are greater in magnitude. Mitochondrial and bioenergetic dysfunction could, therefore, link neurodegeneration to brain aging. Interestingly, mitochondrial defects in AD patients are not brain-limited, and mitochondrial function can be linked to classic AD histologic changes including amyloid precursor protein processing to beta amyloid. Also, transferring mitochondria from AD subjects to cell lines depleted of endogenous mitochondrial DNA (mtDNA) creates cytoplasmic hybrid (cybrid) cell lines that recapitulate specific biochemical, molecular, and histologic AD features. Such findings have led to the formulation of a "mitochondrial cascade hypothesis" that places mitochondrial dysfunction at the apex of the AD pathology pyramid. Data pertinent to this premise are reviewed.
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Lindqvist D, Prokopenko I, Londos E, Middleton L, Hansson O. Associations between TOMM40 Poly-T Repeat Variants and Dementia in Cases with Parkinsonism. JOURNAL OF PARKINSONS DISEASE 2017; 6:99-108. [PMID: 26756745 DOI: 10.3233/jpd-150693] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Mitochondrial dysfunction has been implicated in the pathophysiology of Parkinson's disease (PD)-related pathologies. OBJECTIVE To investigate the role of the Translocase of the Outer Mitochondrial Membrane 40 homolog (TOMM40) variants in PD without dementia (PDND), PD with dementia (PDD) and in Dementia with Lewy bodies (DLB). METHODS 248 individuals, including 92 PDND, 55 PDD, and 101 DLB, were included. The rs10524523 locus in the TOMM40 gene (TOMM40 poly-T repeat) is characterized by a variable number of T residues that were classified into three groups based on length; short (S), long (L), and very long (VL). We tested log-additive genetic model of association with dementia and adjusted for age, sex, and APOEɛ4 carrier status. We analyzed cerebrospinal fluid (CSF) levels of Aβ42 and Tau, biomarkers related to Alzheimer's disease (AD). RESULTS PDD/DBL status and abnormal CSF AD biomarkers (Aβ42 and Aβ42/Tau ratio) were both associated with the APOEɛ4 allele (p < 0.014) and the L allele of TOMM40 poly-T repeat (p < 0.008). The VL allele was less frequently observed in the PDD/DLB group (p = 0.013). In APOE-ɛ4 adjusted analyses, the relationships between the L and VL alleles and dementia status as well as CSF AD biomarkers were not significant. When adjusting for APOE-ɛ4, however, there were associations between S carrier status and PDD/DLB (p = 0.019) and abnormal CSF levels of Aβ42/Tau ratio (p = 0.037) although these were not significant after adjustment for multiple comparisons. CONCLUSION Our results do not support the notion that TOMM40 poly-T repeat variants have independent effects on PDD and DLB pathology. This relationship seems to be driven by APOE-ɛ4.
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Affiliation(s)
- Daniel Lindqvist
- Division of Psychiatry, Department of Clinical Sciences, Lund University, Lund, Sweden.,Psychiatry Skåne, Lund, Sweden
| | - Inga Prokopenko
- Neuroepidemiology and Ageing Research, School of Public Health, Imperial College London, UK
| | - Elisabet Londos
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Memory Clinic, Skåne University Hospital, Lund, Sweden
| | - Lefkos Middleton
- Neuroepidemiology and Ageing Research, School of Public Health, Imperial College London, UK
| | - Oskar Hansson
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Memory Clinic, Skåne University Hospital, Lund, Sweden
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The effects of PPARγ on the regulation of the TOMM40-APOE-C1 genes cluster. Biochim Biophys Acta Mol Basis Dis 2017; 1863:810-816. [PMID: 28065845 DOI: 10.1016/j.bbadis.2017.01.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 12/12/2016] [Accepted: 01/04/2017] [Indexed: 11/24/2022]
Abstract
Chromosome 19q13.32 is a gene rich region, and has been implicated in multiple human phenotypes in adulthood including lipids traits, Alzheimer's disease, and longevity. Peroxisome Proliferator Activated Receptor Gamma (PPARγ) is a ligand-activated nuclear transcription factor that plays a role in human complex traits that are also genetically associated with the chromosome 19q13.32 region. Here, we study the effects of PPARγ on the regional expression regulation of the genes clustered within chromosome 19q13.32, specifically TOMM40, APOE, and APOC1, applying two complementary approaches. Using the short hairpin RNA (shRNA) method in the HepG2 cell-line we knocked down PPARγ expression and measured the effect on mRNA expression. We discovered PPARγ knock down increased the levels of TOMM40-, APOE-, and APOC1-mRNAs, with the highest increase in expression observed for APOE-mRNA. To complement the PPARγ knockdown findings we also examined the effects of low doses of PPARγ agonists (nM range) on mRNA expression of these genes. Low (nM) concentrations of pioglitazone (Pio) decreased transcription of TOMM40, APOE, and APOC1 genes, with the lowest mRNA levels for each gene observed at 1.5nM. Similar to the effect of PPARγ knockdown, the strongest response to pioglitazone was also observed for APOE-mRNA, and rosiglitazone (Rosi), another PPARγ agonist, produced results that were consistent with these. In conclusion, our results further established a role for PPARγ in regional transcriptional regulation of chr19q13.32, underpinning the association between PPARγ, the chr19q13.32 genes cluster, and human complex traits and disease.
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Galimberti D, Scarpini E. Pioglitazone for the treatment of Alzheimer’s disease. Expert Opin Investig Drugs 2016; 26:97-101. [DOI: 10.1080/13543784.2017.1265504] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Daniela Galimberti
- Neurology Unit, Department of Pathophysiology and Transplantation, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Elio Scarpini
- Neurology Unit, Department of Pathophysiology and Transplantation, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
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18
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Plasma levels of apolipoprotein E, APOE genotype and risk of dementia and ischemic heart disease: A review. Atherosclerosis 2016; 255:145-155. [DOI: 10.1016/j.atherosclerosis.2016.10.037] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 10/08/2016] [Accepted: 10/19/2016] [Indexed: 12/12/2022]
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20
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Ghani M, Reitz C, Cheng R, Vardarajan BN, Jun G, Sato C, Naj A, Rajbhandary R, Wang LS, Valladares O, Lin CF, Larson EB, Graff-Radford NR, Evans D, De Jager PL, Crane PK, Buxbaum JD, Murrell JR, Raj T, Ertekin-Taner N, Logue M, Baldwin CT, Green RC, Barnes LL, Cantwell LB, Fallin MD, Go RCP, Griffith PA, Obisesan TO, Manly JJ, Lunetta KL, Kamboh MI, Lopez OL, Bennett DA, Hendrie H, Hall KS, Goate AM, Byrd GS, Kukull WA, Foroud TM, Haines JL, Farrer LA, Pericak-Vance MA, Lee JH, Schellenberg GD, St George-Hyslop P, Mayeux R, Rogaeva E. Association of Long Runs of Homozygosity With Alzheimer Disease Among African American Individuals. JAMA Neurol 2016; 72:1313-23. [PMID: 26366463 DOI: 10.1001/jamaneurol.2015.1700] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
IMPORTANCE Mutations in known causal Alzheimer disease (AD) genes account for only 1% to 3% of patients and almost all are dominantly inherited. Recessive inheritance of complex phenotypes can be linked to long (>1-megabase [Mb]) runs of homozygosity (ROHs) detectable by single-nucleotide polymorphism (SNP) arrays. OBJECTIVE To evaluate the association between ROHs and AD in an African American population known to have a risk for AD up to 3 times higher than white individuals. DESIGN, SETTING, AND PARTICIPANTS Case-control study of a large African American data set previously genotyped on different genome-wide SNP arrays conducted from December 2013 to January 2015. Global and locus-based ROH measurements were analyzed using raw or imputed genotype data. We studied the raw genotypes from 2 case-control subsets grouped based on SNP array: Alzheimer's Disease Genetics Consortium data set (871 cases and 1620 control individuals) and Chicago Health and Aging Project-Indianapolis Ibadan Dementia Study data set (279 cases and 1367 control individuals). We then examined the entire data set using imputed genotypes from 1917 cases and 3858 control individuals. MAIN OUTCOMES AND MEASURES The ROHs larger than 1 Mb, 2 Mb, or 3 Mb were investigated separately for global burden evaluation, consensus regions, and gene-based analyses. RESULTS The African American cohort had a low degree of inbreeding (F ~ 0.006). In the Alzheimer's Disease Genetics Consortium data set, we detected a significantly higher proportion of cases with ROHs greater than 2 Mb (P = .004) or greater than 3 Mb (P = .02), as well as a significant 114-kilobase consensus region on chr4q31.3 (empirical P value 2 = .04; ROHs >2 Mb). In the Chicago Health and Aging Project-Indianapolis Ibadan Dementia Study data set, we identified a significant 202-kilobase consensus region on Chr15q24.1 (empirical P value 2 = .02; ROHs >1 Mb) and a cluster of 13 significant genes on Chr3p21.31 (empirical P value 2 = .03; ROHs >3 Mb). A total of 43 of 49 nominally significant genes common for both data sets also mapped to Chr3p21.31. Analyses of imputed SNP data from the entire data set confirmed the association of AD with global ROH measurements (12.38 ROHs >1 Mb in cases vs 12.11 in controls; 2.986 Mb average size of ROHs >2 Mb in cases vs 2.889 Mb in controls; and 22% of cases with ROHs >3 Mb vs 19% of controls) and a gene-cluster on Chr3p21.31 (empirical P value 2 = .006-.04; ROHs >3 Mb). Also, we detected a significant association between AD and CLDN17 (empirical P value 2 = .01; ROHs >1 Mb), encoding a protein from the Claudin family, members of which were previously suggested as AD biomarkers. CONCLUSIONS AND RELEVANCE To our knowledge, we discovered the first evidence of increased burden of ROHs among patients with AD from an outbred African American population, which could reflect either the cumulative effect of multiple ROHs to AD or the contribution of specific loci harboring recessive mutations and risk haplotypes in a subset of patients. Sequencing is required to uncover AD variants in these individuals.
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Affiliation(s)
- Mahdi Ghani
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Christiane Reitz
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York3Gertrude H. Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, New York4
| | - Rong Cheng
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Badri Narayan Vardarajan
- Gertrude H. Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Gyungah Jun
- Department of Medicine (Biomedical Genetics), Boston University, Boston, Massachusetts6Department of Biostatistics, Boston University, Boston, Massachusetts7Department of Ophthalmology, Boston University, Boston, Massachusetts
| | - Christine Sato
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Adam Naj
- The John P. Hussman Institute for Human Genomics, University of Miami, Miami, Florida
| | - Ruchita Rajbhandary
- The John P. Hussman Institute for Human Genomics, University of Miami, Miami, Florida
| | - Li-San Wang
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Otto Valladares
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Chiao-Feng Lin
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Eric B Larson
- Department of Medicine, University of Washington, Seattle11Group Health Research Institute, Group Health, Seattle, Washington
| | - Neill R Graff-Radford
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida13Department of Neurology, Mayo Clinic, Jacksonville, Florida
| | - Denis Evans
- Rush Institute for Healthy Aging, Department of Internal Medicine, Rush University Medical Center, Chicago, Illinois
| | - Philip L De Jager
- Program in Translational Neuropsychiatric Genomics, Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts16Harvard Medical School, Boston, Massachusetts17Program in Medical and Population Genetics, The Broad Institute, Cambridge, Ma
| | - Paul K Crane
- Department of Medicine, University of Washington, Seattle
| | - Joseph D Buxbaum
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York19Department of Genetics and Genomics Sciences, Mount Sinai School of Medicine, New York, New York20Department of Neuroscience, Mount Sinai School of Medicine, New York, New York2
| | - Jill R Murrell
- Department of Medical and Molecular Genetics, Indiana University, Indianapolis
| | | | - Nilufer Ertekin-Taner
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida13Department of Neurology, Mayo Clinic, Jacksonville, Florida
| | - Mark Logue
- Department of Medicine (Biomedical Genetics), Boston University, Boston, Massachusetts
| | - Clinton T Baldwin
- Department of Medicine (Biomedical Genetics), Boston University, Boston, Massachusetts
| | - Robert C Green
- Harvard Medical School, Boston, Massachusetts23Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts24Partners Center for Personalized Genetic Medicine, Brigham and Women's Hospital, Boston, Massachusetts
| | - Lisa L Barnes
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois26Department of Behavioral Sciences, Rush University Medical Center, Chicago, Illinois
| | - Laura B Cantwell
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - M Daniele Fallin
- Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, Maryland
| | - Rodney C P Go
- School of Public Health, University of Alabama at Birmingham
| | | | | | - Jennifer J Manly
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York4Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Kathryn L Lunetta
- Department of Biostatistics, Boston University, Boston, Massachusetts
| | - M Ilyas Kamboh
- Department of Human Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania32Alzheimer's Disease Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Oscar L Lopez
- Alzheimer's Disease Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - David A Bennett
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois33Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, Illinois
| | - Hugh Hendrie
- Indiana University Center for Aging Research, Indianapolis35Department of Psychiatry, Indiana University School of Medicine, Indianapolis36Regenstrief Institute Inc, Indianapolis, Indiana
| | - Kathleen S Hall
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis
| | - Alison M Goate
- Hope Center Program on Protein Aggregation and Neurodegeneration, Department of Psychiatry, Washington University School of Medicine, St Louis, Missouri
| | - Goldie S Byrd
- Department of Biology, North Carolina A & T University, Greensboro
| | - Walter A Kukull
- National Alzheimer's Coordinating Center, Department of Epidemiology, University of Washington, Seattle
| | - Tatiana M Foroud
- Department of Behavioral Sciences, Rush University Medical Center, Chicago, Illinois
| | - Jonathan L Haines
- Vanderbilt Center for Human Genetics Research, Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Lindsay A Farrer
- Department of Medicine (Biomedical Genetics), Boston University, Boston, Massachusetts6Department of Biostatistics, Boston University, Boston, Massachusetts7Department of Ophthalmology, Boston University, Boston, Massachusetts41Department of Neurology, Bo
| | | | - Joseph H Lee
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York3Gertrude H. Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, New York4
| | - Gerard D Schellenberg
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Peter St George-Hyslop
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Richard Mayeux
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York3Gertrude H. Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, New York4
| | - Ekaterina Rogaeva
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
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Gottschalk WK, Mihovilovic M, Roses AD, Chiba-Falek O. The Role of Upregulated APOE in Alzheimer's Disease Etiology. ACTA ACUST UNITED AC 2016; 6. [PMID: 27104063 PMCID: PMC4836841 DOI: 10.4172/2161-0460.1000209] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
| | - Mirta Mihovilovic
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA
| | - Allen D Roses
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA; Zinfandel Pharmaceuticals, Chapel Hill, NC, USA
| | - Ornit Chiba-Falek
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA; Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC 27710, USA
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Postnatal high-fat diet enhances ectopic fat deposition in pigs with intrauterine growth retardation. Eur J Nutr 2015; 56:483-490. [PMID: 26707995 DOI: 10.1007/s00394-015-1093-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 10/26/2015] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Intrauterine growth retardation (IUGR) and postnatal nutrition are risk factors for adult metabolic syndrome. However, the influences of long-term high-fat diet (HFD) intake on ectopic fat deposition in non-adipose tissues in IUGR pigs remain unclear. The present study was to determine whether HFD consumption would enhance ectopic fat deposition in IUGR pigs. METHODS At day 28, IUGR and control pigs were fed ad libitum to either a regular diet or a HFD. Lipid store, enzymatic activities and mRNA expression of lipid metabolism-related factors in liver and semitendinosus muscle (SM) were quantified at postnatal day 178. RESULTS Feeding a HFD to IUGR pigs but not to control pigs significantly increased daily weight gain, carcass fat mass, plasma leptin level and lipid content and lipoprotein lipase (LPL) activity and mRNA abundances of LPL and peroxisome proliferator-activated receptor gamma (PPARγ) in liver and SM, but decreased daily feed intake and mRNA expression of hormone-sensitive lipase (LIPE) and carnitine palmitoyl transferase-1 (CPT-1) in liver and SM (P < 0.05). Compared with control pigs, IUGR pigs had a lower body weight but higher plasma levels of total cholesterol (TC) and insulin (P < 0.05). HFD-fed pigs exhibited greater body weight, plasma concentrations of triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), regardless of birth weight (P < 0.05). CONCLUSION Our results suggested that IUGR increased the vulnerability of HFD-fed pigs to ectopic fat deposition via enhanced fatty acid flux toward ectopic sites and reduced lipolysis and fatty acid oxidation.
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Talwar P, Sinha J, Grover S, Agarwal R, Kushwaha S, Srivastava MVP, Kukreti R. Meta-analysis of apolipoprotein E levels in the cerebrospinal fluid of patients with Alzheimer's disease. J Neurol Sci 2015; 360:179-87. [PMID: 26723997 DOI: 10.1016/j.jns.2015.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 11/28/2015] [Accepted: 12/02/2015] [Indexed: 11/17/2022]
Abstract
The possible association between Apolipoprotein E (ApoE) levels in the cerebrospinal fluid (CSF) and Alzheimer's disease (AD) has been studied extensively. However, previous findings have been inconsistent. We conducted a meta-analysis of observational studies, seeking to provide insights into ApoE's potential as a biomarker for AD. A systematic literature search of PubMed (MEDLINE), EMBASE, and Web of Science was performed to retrieve relevant studies evaluating ApoE levels in CSF from AD subjects and controls. The association between ApoE levels in the CSF and AD was estimated by the weighted mean difference (WMD) and 95% confidence interval (CI) using a random-effect model. We identified 24 studies that included 1064AD cases and 1338 non-demented controls. Although the pooled WMD did not indicate a significant association between AD and ApoE levels (-0.30mg/l; 95% CI: -0.69 to 0.09; P=0.13), sub-group analysis controlling for patient sample size (n≥43) revealed significantly lower ApoE levels (WMD: -0.66mg/l; 95% CI: -1.02 to -0.31; P=0.0002) among patients with AD than in controls. Publication bias was absent and sensitivity analysis did not result in any significant change in the pooled estimates, indicating highly stable results. The present meta-analysis indicates the potential of CSF ApoE levels as a predictor of AD association.
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Affiliation(s)
- Puneet Talwar
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB) Campus, New Delhi, India; Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi, India
| | - Juhi Sinha
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi, India
| | - Sandeep Grover
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi, India; Department of Paediatrics, Division of Pneumonology-Immunology, Charité University Medical Centre, Berlin, Germany
| | - Rachna Agarwal
- Institute of Human Behaviour and Allied Sciences (IHBAS), Delhi, India
| | - Suman Kushwaha
- Institute of Human Behaviour and Allied Sciences (IHBAS), Delhi, India
| | - M V Padma Srivastava
- Department of Neurology, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Ritushree Kukreti
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB) Campus, New Delhi, India; Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi, India.
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Pappas A, Chaiworapongsa T, Romero R, Korzeniewski SJ, Cortez JC, Bhatti G, Gomez-Lopez N, Hassan SS, Shankaran S, Tarca AL. Transcriptomics of maternal and fetal membranes can discriminate between gestational-age matched preterm neonates with and without cognitive impairment diagnosed at 18-24 months. PLoS One 2015; 10:e0118573. [PMID: 25822971 PMCID: PMC4379164 DOI: 10.1371/journal.pone.0118573] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 01/20/2015] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Neurocognitive impairment among children born preterm may arise from complex interactions between genes and the intra-uterine environment. OBJECTIVES (1) To characterize the transcriptomic profiles of chorioamniotic membranes in preterm neonates with and without neurocognitive impairment via microarrays and (2) to determine if neonates with neurocognitive impairment can be identified at birth. MATERIALS/METHODS A retrospective case-control study was conducted to examine the chorioamniotic transcriptome of gestational-age matched very preterm neonates with and without neurocognitive impairment at 18-24 months' corrected-age defined by a Bayley-III Cognitive Composite Score <80 (n = 14 each). Pathway analysis with down-weighting of overlapping genes (PADOG) was performed to identify KEGG pathways relevant to the phenotype. Select differentially expressed genes were profiled using qRT-PCR and a multi-gene disease prediction model was developed using linear discriminant analysis. The model's predictive performance was tested on a new set of cases and controls (n = 19 each). RESULTS 1) 117 genes were differentially expressed among neonates with and without subsequent neurocognitive impairment (p<0.05 and fold change >1.5); 2) Gene ontology analysis indicated enrichment of 19 biological processes and 3 molecular functions; 3)PADOG identified 4 significantly perturbed KEGG pathways: oxidative phosphorylation, Parkinson's disease, Alzheimer's disease and Huntington's disease (q-value <0.1); 4) 48 of 90 selected differentially expressed genes were confirmed by qRT-PCR, including genes implicated in energy metabolism, neuronal signaling, vascular permeability and response to injury (e.g., up-regulation of SEPP1, APOE, DAB2, CD163, CXCL12, VWF; down-regulation of HAND1, OSR1)(p<0.05); and 5) a multi-gene model predicted 18-24 month neurocognitive impairment (using the ratios of OSR1/VWF and HAND1/VWF at birth) in a larger, independent set (sensitivity = 74%, at specificity = 83%). CONCLUSIONS Gene expression patterns in the chorioamniotic membranes link neurocognitive impairment in preterm infants to neurodegenerative disease pathways and might be used to predict neurocognitive impairment. Further prospective studies are needed.
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Affiliation(s)
- Athina Pappas
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Pediatrics, Division of Neonatal and Perinatal Medicine, Wayne State University, Detroit, MI, United States of America
- * E-mail: (AP); (AT)
| | - Tinnakorn Chaiworapongsa
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States of America
| | - Roberto Romero
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, United States of America
- Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, MI, United States of America
| | - Steven J. Korzeniewski
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States of America
- Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, MI, United States of America
| | - Josef C. Cortez
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Pediatrics, Division of Neonatal and Perinatal Medicine, Wayne State University, Detroit, MI, United States of America
| | - Gaurav Bhatti
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
| | - Nardhy Gomez-Lopez
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States of America
- Department of Immunology and Microbiology, Wayne State University, Detroit, MI, United States of America
| | - Sonia S. Hassan
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States of America
| | - Seetha Shankaran
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Pediatrics, Division of Neonatal and Perinatal Medicine, Wayne State University, Detroit, MI, United States of America
| | - Adi L. Tarca
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development / NIH / DHHS, Bethesda, MD and Detroit, MI, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States of America
- * E-mail: (AP); (AT)
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Rasmussen KL, Tybjaerg-Hansen A, Nordestgaard BG, Frikke-Schmidt R. Plasma levels of apolipoprotein E and risk of dementia in the general population. Ann Neurol 2015; 77:301-11. [PMID: 25469919 DOI: 10.1002/ana.24326] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 11/25/2014] [Accepted: 11/26/2014] [Indexed: 12/13/2022]
Abstract
OBJECTIVE The apolipoprotein E (APOE) ε4 allele is a major genetic risk factor for Alzheimer disease and dementia. However, it remains unclear whether plasma levels of apoE confer additional risk. We tested this hypothesis. METHODS Using 75,708 participants from the general population, we tested whether low plasma levels of apoE at study enrollment were associated with increased risk of future Alzheimer disease and all dementia, and whether this association was independent of ε2/ε3/ε4 APOE genotype. RESULTS Multifactorially adjusted hazard ratios (HRs) for Alzheimer disease and all dementia increased from the highest to the lowest apoE tertile (p for trends < 1 × 10(-6) ). Multifactorially adjusted HRs for lowest versus highest tertile were 2.68 (95% confidence interval [CI] = 2.04-3.52) and 1.80 (95% CI = 1.52-2.13) for Alzheimer disease and all dementia, respectively. After further adjustment for ε2/ε3/ε4 APOE genotype, plasma apoE tertiles remained associated with Alzheimer disease (p for trend = 0.007) and all dementia (p for trend = 0.04). Plasma apoE tertiles did not interact with ε2/ε3/ε4 APOE genotype on risk of Alzheimer disease (p = 0.53) or all dementia (p = 0.79). In a subanalysis, the -219G>T GT promoter genotype, associated with low plasma apoE levels, remained significantly associated with increased risk of Alzheimer disease after adjustment for ε2/ε3/ε4 APOE genotype (HR = 1.56, 95% CI = 1.05-2.30). INTERPRETATION Low plasma levels of apoE are associated with increased risk of future Alzheimer disease and all dementia in the general population, independent of ε2/ε3/ε4 APOE genotype. This is clinically relevant, because no plasma biomarkers are currently implemented. Hence, plasma levels of apoE may be a new, easily accessible preclinical biomarker.
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Affiliation(s)
- Katrine L Rasmussen
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen; Copenhagen University Hospital and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen
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26
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Salem N, Vandal M, Calon F. The benefit of docosahexaenoic acid for the adult brain in aging and dementia. Prostaglandins Leukot Essent Fatty Acids 2015; 92:15-22. [PMID: 25457546 DOI: 10.1016/j.plefa.2014.10.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 10/08/2014] [Indexed: 01/08/2023]
Abstract
A brief overview of the evidence for omega-3 fatty acids and, in particular, of docosahexaenoic acid (DHA), involvement in cognition and in dementia is given. Two studies are presented in this regard in which the key intervention is a DHA supplement. The fist, the MIDAS Study demonstrated that DHA can be of benefit for episodic memory in healthy adults with a mild memory complaint. The second, the ADCS AD trial found no benefit of DHA in the primary outcomes but found an intriguing benefit for cognitive score in ApoE4 negative allele patients. This leads to a consideration of the mechanisms of action and role of ApoE and its modulation by DHA. Given the fundamental role of ApoE in cellular lipid transport and metabolism in the brain and periphery, it is no surprise that ApoE affects n-3 PUFA brain function as well. It remains to be seen to what extent ApoE4 deleterious effect in AD is associated with n-3 PUFA-related cellular mechanisms in the brain and, more specifically, whether ApoE4 directly impairs the transport of DHA into the brain, as has been suggested.
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Affiliation(s)
- Norman Salem
- Nutritional Lipids, DSM Nutritional Products, Columbia, MD, USA.
| | - Milene Vandal
- Center de recherche du center Hospitalier de l׳Université Laval (CHUL), Québec, QC, Canada; Faculté de pharmacie, Université Laval, Quebec, Canada; Institut des Nutraceutiques et des Aliments Fonctionnels, Universite Laval, Quebec, Canada
| | - Frederic Calon
- Center de recherche du center Hospitalier de l׳Université Laval (CHUL), Québec, QC, Canada; Faculté de pharmacie, Université Laval, Quebec, Canada; Institut des Nutraceutiques et des Aliments Fonctionnels, Universite Laval, Quebec, Canada
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27
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Hudry E, Dashkoff J, Roe AD, Takeda S, Koffie RM, Hashimoto T, Scheel M, Spires-Jones T, Arbel-Ornath M, Betensky R, Davidson BL, Hyman BT. Gene transfer of human Apoe isoforms results in differential modulation of amyloid deposition and neurotoxicity in mouse brain. Sci Transl Med 2014; 5:212ra161. [PMID: 24259049 DOI: 10.1126/scitranslmed.3007000] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Inheritance of the ε4 allele of apolipoprotein E (APOE) is the strongest genetic risk factor associated with the sporadic form of Alzheimer's disease (AD), whereas the rare APOE ε2 allele has the opposite effect. However, the mechanisms whereby APOE confers risk and protection remain uncertain. We used a gene transfer approach to bathe the cortex of amyloid plaque-bearing transgenic mice with virally expressed human APOE. We monitored amyloid-β (Aβ) with multiphoton imaging, in vivo microdialysis, and postmortem array tomography to study the kinetics of human APOE-mediated changes in Aβ-related neurotoxicity in a mouse model of AD. We observed that human APOE4 increased the concentrations of oligomeric Aβ within the interstitial fluid and exacerbated plaque deposition; the converse occurred after exposure to human APOE2. Peri-plaque synapse loss and dystrophic neurites were also worsened by APOE4 or attenuated by APOE2. Egress of Aβ from the central nervous system (CNS) into the plasma was diminished by APOE3 and APOE4 compared to APOE2, in accord with isoform-specific retention of Aβ in the CNS. Overall, our data show a differential effect of human APOE isoforms on amyloid deposition and clearance in transgenic mice and, more importantly, on Aβ-mediated synaptotoxicity. These results suggest that the APOE genetic risk is mediated by Aβ, and that therapeutic approaches aimed at decreasing APOE4, or increasing APOE2, may be beneficial in AD.
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Affiliation(s)
- Eloise Hudry
- MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
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28
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Mills JD, Sheahan PJ, Lai D, Kril JJ, Janitz M, Sutherland GT. The alternative splicing of the apolipoprotein E gene is unperturbed in the brains of Alzheimer’s disease patients. Mol Biol Rep 2014; 41:6365-76. [DOI: 10.1007/s11033-014-3516-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Accepted: 06/19/2014] [Indexed: 12/20/2022]
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29
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McFarquhar M, Elliott R, McKie S, Thomas E, Downey D, Mekli K, Toth ZG, Anderson IM, Deakin JFW, Juhasz G. TOMM40 rs2075650 may represent a new candidate gene for vulnerability to major depressive disorder. Neuropsychopharmacology 2014; 39:1743-53. [PMID: 24549102 PMCID: PMC4023148 DOI: 10.1038/npp.2014.22] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 12/19/2013] [Accepted: 01/17/2014] [Indexed: 01/15/2023]
Abstract
Evidence suggests that depression is a risk factor for dementia; however, the relationship between the two conditions is not fully understood. A novel gene (TOMM40) has been consistently associated with Alzheimer's disease (AD), but has received no attention in depression. We conducted a three-level cross-sectional study to investigate the association of the TOMM40 rs2075650 SNP with depression. We recruited a community sample of 1220 participants (571 controls, 649 lifetime depression) to complete a psychiatric background questionnaire, the Brief Symptom Inventory, and Big Five Inventory at Level-1, 243 (102 controls, 97 remitted, 44 currently depressed) to complete a face-to-face clinical interview and neuropsychological testing at Level-2 and 58 (33 controls, 25 remitted) to complete an emotional face-processing task during fMRI at Level-3. Our results indicated that the TOMM40 rs2075650 G allele was a significant risk factor for lifetime depression (p = 0.00006) and, in depressed subjects, was a significant predictor of low extraversion (p = 0.009). Currently depressed risk allele carriers showed subtle executive dysfunction (p = 0.004) and decreased positive memory bias (p = 0.021) together with reduced activity in the posterior (p(FWE) = 0.045) and anterior (p(FWE) = 0.041) cingulate during sad face emotion processing. Our results suggest that TOMM40 rs2075650 may be a risk factor for the development of depression characterized by reduced extraversion, impaired executive function, and decreased positive emotional recall, and reduced top-down cortical control during sad emotion processing.
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Affiliation(s)
- Martyn McFarquhar
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Rebecca Elliott
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Shane McKie
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Emma Thomas
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Darragh Downey
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Krisztina Mekli
- Cathie Marsh Centre for Census and Survey Research, School of Social Sciences, Faculty of Humanities, University of Manchester, Manchester, UK
| | - Zoltan G Toth
- Kalman Kando Faculty of Electrical Engineering, Obuda University, Budapest, Hungary
| | - Ian M Anderson
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - JF William Deakin
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Gabriella Juhasz
- Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK,Department of Pharmacodynamics, Faculty of Pharmacy, Semmelweis University, and MTA-SE, Neuropsychopharmacology and Neurochemistry Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest, Hungary,Neuroscience and Psychiatry Unit, School of Community Based Medicine, Faculty of Medical and Human Sciences, University of Manchester, G.907 Stopford Building, Oxford Road, Manchester M13 9PL, UK, Tel: +44 161 275 6915, Fax: +44 161 275 7429, E-mail:
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30
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Natunen T, Martiskainen H, Sarajärvi T, Helisalmi S, Pursiheimo JP, Viswanathan J, Laitinen M, Mäkinen P, Kauppinen T, Rauramaa T, Leinonen V, Alafuzoff I, Haapasalo A, Soininen H, Hiltunen M. Effects of NR1H3 genetic variation on the expression of liver X receptor α and the progression of Alzheimer's disease. PLoS One 2013; 8:e80700. [PMID: 24278306 PMCID: PMC3835410 DOI: 10.1371/journal.pone.0080700] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 10/16/2013] [Indexed: 01/19/2023] Open
Abstract
Alzheimer's disease (AD) has been postulated to involve defects in the clearance of amyloid-β (Aβ). Activation of liver X receptor α (LXRα) increases the expression of apolipoprotein E (ApoE) as well as cholesterol transporters ABCA1 and ABCG1, leading to augmented clearance of Aβ. We have previously shown that the C allele of rs7120118 in the NR1H3 gene encoding LXRα reduces the risk of AD. Here, we wanted to assess whether the rs7120118 variation affects the progression of AD and modulates the expression of NR1H3 and its downstream targets APOE, ABCA1 and ABCG1.We utilized tissue samples from the inferior temporal cortex of 87 subjects, which were subdivided according to Braak staging into mild, moderate and severe AD groups on the basis of AD-related neurofibrillary pathology. APOE ε4 allele increased soluble Aβ42 levels in the tissue samples in a dose-dependent manner, but did not affect the expression status of APOE. In contrast, the CC genotype of rs7120118 was underrepresented in the severe group, although this result did not reach statistical significance. Also, patients with the CC genotype of rs7120118 showed significantly decreased soluble Aβ42 levels as compared to the patients with TT genotype. Although the severity of AD did not affect NR1H3 expression, the mRNA levels of NR1H3 among the patients with CT genotype of rs7120118 were significantly increased as compared to the patients with TT genotype. These results suggest that genetic variation in NR1H3 modulates the expression of LXRα and the levels of soluble Aβ42.
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Affiliation(s)
- Teemu Natunen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Henna Martiskainen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Timo Sarajärvi
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Seppo Helisalmi
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | | | - Jayashree Viswanathan
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Marjo Laitinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Petra Mäkinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Tarja Kauppinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Tuomas Rauramaa
- Department of Pathology, Kuopio University Hospital, Finland and Institute of Clinical Medicine, Unit of Pathology, University of Eastern Finland, Kuopio, Finland
| | - Ville Leinonen
- Institute of Clinical Medicine – Neurosurgery, University of Eastern Finland and Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland
| | - Irina Alafuzoff
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Annakaisa Haapasalo
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Hilkka Soininen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Mikko Hiltunen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
- * E-mail:
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31
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Omoumi A, Fok A, Greenwood T, Sadovnick AD, Feldman HH, Hsiung GYR. Evaluation of late-onset Alzheimer disease genetic susceptibility risks in a Canadian population. Neurobiol Aging 2013; 35:936.e5-12. [PMID: 24176626 DOI: 10.1016/j.neurobiolaging.2013.09.025] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 09/16/2013] [Accepted: 09/19/2013] [Indexed: 10/26/2022]
Abstract
We performed case-control studies using 2 Canadian cohorts to examine the role of 10 promising Alzheimer's disease (AD) loci identified in recent genomewide association studies. Patients age 65 years and older diagnosed with AD at baseline (prevalent cases) or who developed AD during follow-up assessments (incident cases) were compared with control subjects with no cognitive impairment. Our prevalent case study comparing prevalent AD cases (n = 428) with participants with no cognitive impairment (n = 524) revealed a significant association of rs6656401 and rs3818361 (CR1), rs2075650 (TOMM40), rs7561528 (BIN1), and rs3865444 (CD33) with late-onset AD that were robust to adjustment with age and apolipoprotein E ε4 genotype. The incident case study comparing patients who developed AD during longitudinal observation (n = 152) with participants with no cognitive impairment found that rs2075650 (TOMM40) and rs3865444 (CD33) influence the risk of developing AD in this population. In addition, pooled analysis of our AD patients confirmed that CR1, TOMM40, BIN1, and CD33 contribute to late-onset AD susceptibility, in addition to apolipoprotein E.
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Affiliation(s)
- Ardeshir Omoumi
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Alice Fok
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Talitha Greenwood
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
| | - A Dessa Sadovnick
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
| | - Howard H Feldman
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Ging-Yuek R Hsiung
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, Canada.
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32
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Li G, Bekris LM, Leong L, Steinbart EJ, Shofer JB, Crane PK, Larson EB, Peskind ER, Bird TD, Yu CE. TOMM40 intron 6 poly-T length, age at onset, and neuropathology of AD in individuals with APOE ε3/ε3. Alzheimers Dement 2013; 9:554-61. [PMID: 23183136 PMCID: PMC3606272 DOI: 10.1016/j.jalz.2012.06.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 05/17/2012] [Accepted: 06/19/2012] [Indexed: 01/18/2023]
Abstract
BACKGROUND This study investigates the association between TOMM40 poly-T length, age at onset, and neuropathology in individuals with Alzheimer's disease (AD) with the apolipoprotein E (APOE) ε3/ε3 allele. METHODS Thirty-two presenilin 1 (PSEN1) mutation carriers with AD, 27 presenilin 2 (PSEN2) mutation carriers with AD, 59 participants with late-onset AD (LOAD), and 168 autopsied subjects from a community-based cohort were genotyped for TOMM40 intron 6 poly-T (rs10524523) length using short tandem repeat assays. RESULTS Among AD individuals with PSEN2 mutations, the presence of a long poly-T was associated with an earlier age at onset, whereas there were no such associations for subjects with PSEN1 mutations or LOAD. In community-based participants, the presence of a long poly-T was associated with increased neuritic tangles and a greater likelihood of pathologically diagnosed AD. CONCLUSION TOMM40 intron 6 poly-T length may explain some of the variation in age at onset in PSEN2 familial AD and may be associated with AD neuropathology in persons with APOE ε3/ε3.
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Affiliation(s)
- Ge Li
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
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33
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Yu CE, Cudaback E, Foraker J, Thomson Z, Leong L, Lutz F, Gill JA, Saxton A, Kraemer B, Navas P, Keene CD, Montine T, Bekris LM. Epigenetic signature and enhancer activity of the human APOE gene. Hum Mol Genet 2013; 22:5036-47. [PMID: 23892237 DOI: 10.1093/hmg/ddt354] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The human apolipoprotein E (APOE) gene plays an important role in lipid metabolism. It has three common genetic variants, alleles ε2/ε3/ε4, which translate into three protein isoforms of apoE2, E3 and E4. These isoforms can differentially influence total serum cholesterol levels; therefore, APOE has been linked with cardiovascular disease. Additionally, its ε4 allele is strongly associated with the risk of Alzheimer's disease (AD), whereas the ε2 allele appears to have a modest protective effect for AD. Despite decades of research having illuminated multiple functional differences among the three apoE isoforms, the precise mechanisms through which different APOE alleles modify diseases risk remain incompletely understood. In this study, we examined the genomic structure of APOE in search for properties that may contribute novel biological consequences to the risk of disease. We identify one such element in the ε2/ε3/ε4 allele-carrying 3'-exon of APOE. We show that this exon is imbedded in a well-defined CpG island (CGI) that is highly methylated in the human postmortem brain. We demonstrate that this APOE CGI exhibits transcriptional enhancer/silencer activity. We provide evidence that this APOE CGI differentially modulates expression of genes at the APOE locus in a cell type-, DNA methylation- and ε2/ε3/ε4 allele-specific manner. These findings implicate a novel functional role for a 3'-exon CGI and support a modified mechanism of action for APOE in disease risk, involving not only the protein isoforms but also an epigenetically regulated transcriptional program at the APOE locus driven by the APOE CGI.
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Affiliation(s)
- Chang-En Yu
- Geriatric Research, Education, and Clinical Center, VA Puget Sound Health Care System, Seattle, WA 98108, USA
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Decourt B, Gonzales A, Beach TG, Malek-Ahmadi M, Walker A, Sue L, Walker DG, Sabbagh MN. BACE1 levels by APOE genotype in non-demented and Alzheimer's post-mortem brains. Curr Alzheimer Res 2013; 10:309-15. [PMID: 23036023 PMCID: PMC4104947 DOI: 10.2174/1567205011310030010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 08/13/2012] [Accepted: 08/27/2012] [Indexed: 01/04/2023]
Abstract
The APOE genotype is a known susceptibility factor for Alzheimer's disease (AD). It is apparent that the presence of the APOE ε40 allele increases the risk for developing AD, lowers the age of onset in AD, and may influence the pathological burden seen in AD. In this study, we asked whether BACE1 levels differ by APOE genotype in the AD and non-demented (ND) brain. We isolated mid-frontal cortex (MFC) and mid-temporal cortex (MTC) from post-mortem ND and AD subjects that were APOE ε3/3, ε3/4, ε4/4 carriers. All AD subjects met NINDS-ADRDA and NIA-Reagan criteria for a diagnosis of AD. The MFC and MTC were homogenized and the lysates underwent ELISA and Western blotting for BACE1. The ELISA revealed that total BACE1 levels were lower in the MFC of AD compared to ND subjects. Furthermore, in APOE ε4 carriers BACE1 levels were lower than ε3/3 carriers in the ND frontal cortex. No difference in BACE1 levels was observed in AD MFC and in ND and AD MTC tissues. The ELISA results were confirmed by Western blotting. Our data suggest that brain BACEl levels may be influenced by the apolipoprotein E genotype before the onset of AD, providing an alternative explanation for the lower amyloid beta 42 levels in CSF in ND and AD subjects.
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Affiliation(s)
- Boris Decourt
- Haldeman Laboratory of Molecular Diagnostics and Therapeutics, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Amanda Gonzales
- Haldeman Laboratory of Molecular Diagnostics and Therapeutics, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Thomas G. Beach
- Civin Laboratory of Neuropathology, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Michael Malek-Ahmadi
- Cleo Roberts Center for Clinical Research, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Aaron Walker
- Haldeman Laboratory of Molecular Diagnostics and Therapeutics, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Lucia Sue
- Civin Laboratory of Neuropathology, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Douglas G. Walker
- Laboratory of Neuroregeneration, Banner Sun Health Research Institute, Sun City AZ 85351, USA
| | - Marwan N. Sabbagh
- Haldeman Laboratory of Molecular Diagnostics and Therapeutics, Banner Sun Health Research Institute, Sun City AZ 85351, USA
- Cleo Roberts Center for Clinical Research, Banner Sun Health Research Institute, Sun City AZ 85351, USA
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Association of TOMM40 Polymorphisms with Late-Onset Alzheimer’s Disease in a Northern Han Chinese Population. Neuromolecular Med 2013; 15:279-87. [DOI: 10.1007/s12017-012-8217-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 12/22/2012] [Indexed: 02/08/2023]
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Barber RC. The genetics of Alzheimer's disease. SCIENTIFICA 2012; 2012:246210. [PMID: 24278680 PMCID: PMC3820554 DOI: 10.6064/2012/246210] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 11/28/2012] [Indexed: 06/02/2023]
Abstract
Alzheimer's disease is a progressive, neurodegenerative disease that represents a growing global health crisis. Two major forms of the disease exist: early onset (familial) and late onset (sporadic). Early onset Alzheimer's is rare, accounting for less than 5% of disease burden. It is inherited in Mendelian dominant fashion and is caused by mutations in three genes (APP, PSEN1, and PSEN2). Late onset Alzheimer's is common among individuals over 65 years of age. Heritability of this form of the disease is high (79%), but the etiology is driven by a combination of genetic and environmental factors. A large number of genes have been implicated in the development of late onset Alzheimer's. Examples that have been confirmed by multiple studies include ABCA7, APOE, BIN1, CD2AP, CD33, CLU, CR1, EPHA1, MS4A4A/MS4A4E/MS4A6E, PICALM, and SORL1. Despite tremendous progress over the past three decades, roughly half of the heritability for the late onset of the disease remains unidentified. Finding the remaining genetic factors that contribute to the development of late onset Alzheimer's disease holds the potential to provide novel targets for treatment and prevention, leading to the development of effective strategies to combat this devastating disease.
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Affiliation(s)
- Robert C. Barber
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
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Chiba-Falek O, Linnertz C, Guyton J, Gardner SD, Roses AD, McCarthy JJ, Patel K. Pleiotropy and allelic heterogeneity in the TOMM40-APOE genomic region related to clinical and metabolic features of hepatitis C infection. Hum Genet 2012; 131:1911-20. [PMID: 22898894 DOI: 10.1007/s00439-012-1220-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 08/08/2012] [Indexed: 12/11/2022]
Abstract
Hepatitis C virus (HCV) modulates host lipid metabolism as part of its lifecycle and is dependent upon VLDL for co-assembly and secretion. HCV dyslipidemia is associated with steatosis, insulin resistance, IL28B genotype and disease progression. Apolipoprotein E (ApoE) is an important lipid transport protein, a key constituent of VLDL, and is involved in immunomodulation. Our aims were to determine the role of APOE regional polymorphisms on host lipids, IL28B genotype and disease severity in chronic HCV (CHC) patients. The study cohort included 732 CHC patients with available DNA for genotype determination of four polymorphisms in the chromosome 19 region that encompasses the TOMM40, APOE and APOC1 genes. Serum lipid analysis and apolipoproteins levels were measured using an immunoturbidimetric assay. APOE rs7412 polymorphism (capturing the ε2 isoform) was significantly associated with serum ApoE levels in both Caucasians and African-American patients (p = 2.3 × 10(-11)) and explained 7 % of variance in serum ApoE. Among IL28B-CC patients (n = 196), the rs429358 (defines ε4 isoform) and TOMM40 '523' S polymorphisms were associated with 12 % of variance in ApoB levels. Patients homozygous for the APOE ε3 isoform had a greater than twofold increased odds of F2-F4 fibrosis (p = 1.8 × 10(-5)), independent of serum lipid and lipoprotein levels. There were no associations between APOE polymorphisms and serum HDL-C, APO-CIII and triglycerides. In CHC patients, genetic heterogeneity in the APOE/TOMM40 genomic region is significantly associated with variation in serum ApoE and ApoB levels, and also with fibrosis suggesting a pleiotropic attribute of this genomic region.
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Affiliation(s)
- Ornit Chiba-Falek
- Division of Neurology, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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APOE and neuroenergetics: an emerging paradigm in Alzheimer's disease. Neurobiol Aging 2012; 34:1007-17. [PMID: 23159550 DOI: 10.1016/j.neurobiolaging.2012.10.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 10/13/2012] [Accepted: 10/15/2012] [Indexed: 12/29/2022]
Abstract
APOE is the major known genetic risk factor for late-onset Alzheimer's disease. Though relationships between APOE-encoded apolipoprotein E and β-amyloid are increasingly well described, mounting evidence supports wide-ranging effects of APOE on the brain. Specifically, APOE appears to affect brain network activity and closely related neuroenergetic functions that might be involved in vulnerability to neurodegenerative pathophysiology. These effects highlight the salience of further investigation into the diverse influences of APOE. Therefore, this article reviews the interplay between APOE and neuroenergetics and proposes areas for further investigation. This research might lead to the identification of novel therapeutic targets for the treatment and/or prevention of Alzheimer's disease.
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Swerdlow RH. Mitochondria and cell bioenergetics: increasingly recognized components and a possible etiologic cause of Alzheimer's disease. Antioxid Redox Signal 2012; 16:1434-55. [PMID: 21902597 PMCID: PMC3329949 DOI: 10.1089/ars.2011.4149] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 07/28/2011] [Indexed: 12/28/2022]
Abstract
SIGNIFICANCE Mitochondria and brain bioenergetics are increasingly thought to play an important role in Alzheimer's disease (AD). RECENT ADVANCES Data that support this view are discussed from the perspective of the amyloid cascade hypothesis, which assumes beta-amyloid perturbs mitochondrial function, and from an opposite perspective that assumes mitochondrial dysfunction promotes brain amyloidosis. A detailed review of cytoplasmic hybrid (cybrid) studies, which argue mitochondrial DNA (mtDNA) contributes to sporadic AD, is provided. Recent AD endophenotype data that further suggest an mtDNA contribution are also summarized. CRITICAL ISSUES AND FUTURE DIRECTIONS Biochemical, molecular, cybrid, biomarker, and clinical data pertinent to the mitochondria-bioenergetics-AD nexus are synthesized and the mitochondrial cascade hypothesis, which represents a mitochondria-centric attempt to conceptualize sporadic AD, is discussed.
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Affiliation(s)
- Russell H Swerdlow
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, USA.
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Guerreiro RJ, Gustafson DR, Hardy J. The genetic architecture of Alzheimer's disease: beyond APP, PSENs and APOE. Neurobiol Aging 2012; 33:437-56. [PMID: 20594621 PMCID: PMC2980860 DOI: 10.1016/j.neurobiolaging.2010.03.025] [Citation(s) in RCA: 174] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 03/01/2010] [Accepted: 03/11/2010] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is a complex disorder with a clear genetic component. Three genes have been identified as the cause of early onset familial AD (EOAD). The most common form of the disease, late onset Alzheimer's disease (LOAD), is, however, a sporadic one presenting itself in later stages of life. The genetic component of this late onset form of AD has been the target of a large number of studies, because only one genetic risk factor (APOE4) has been consistently associated with the disease. However, technological advances allow new approaches in the study of complex disorders. In this review, we discuss the new results produced by genome wide association studies, in light of the current knowledge of the complexity of AD genetics.
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Affiliation(s)
- Rita J Guerreiro
- Laboratory of Neurogenetics, National Institute of Aging, National Institutes of Health, Bethesda, MD, USA.
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Logue MW, Schu M, Vardarajan BN, Buros J, Green RC, Go RCP, Griffith P, Obisesan TO, Shatz R, Borenstein A, Cupples LA, Lunetta KL, Fallin MD, Baldwin CT, Farrer LA. A comprehensive genetic association study of Alzheimer disease in African Americans. ACTA ACUST UNITED AC 2012; 68:1569-79. [PMID: 22159054 DOI: 10.1001/archneurol.2011.646] [Citation(s) in RCA: 186] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVES To evaluate the association of genetic variation with late-onset Alzheimer disease (AD) in African Americans, including genes implicated in recent genome-wide association studies of whites. DESIGN We analyzed a genome-wide set of 2.5 million imputed markers to evaluate the genetic basis of AD in an African American population. SUBJECTS Five hundred thirteen well-characterized African American AD cases and 496 cognitively normal African American control subjects. SETTING Data were collected from multiple sites as part of the Multi-Institutional Research on Alzheimer Genetic Epidemiology (MIRAGE) Study and the Henry Ford Health System as part of the Genetic and Environmental Risk Factors for Alzheimer Disease Among African Americans (GenerAAtions) Study. RESULTS Several significant single-nucleotide polymorphisms (SNPs) were observed in the region of the apolipoprotein E gene (APOE). After adjusting for the confounding effects of APOE genotype, one of these SNPs, rs6859 in PVRL2, remained significantly associated with AD (P = .0087). Association was also observed with SNPs in CLU, PICALM, BIN1, EPHA1, MS4A, ABCA7, and CD33, although the effect direction for some SNPs and the most significant SNPs differed from findings in data sets consisting of whites. Finally, using the African American genome-wide association study data set as a discovery sample, we obtained suggestive evidence of association with SNPs for several novel candidate genes. CONCLUSIONS Some genes contribute to AD pathogenesis in both white and African American cohorts, although it is unclear whether the causal variants are the same. A larger African American sample will be needed to confirm novel gene associations, which may be population specific.
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Affiliation(s)
- Mark W Logue
- Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
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Hampel H, Prvulovic D, Teipel S, Jessen F, Luckhaus C, Frölich L, Riepe MW, Dodel R, Leyhe T, Bertram L, Hoffmann W, Faltraco F. The future of Alzheimer's disease: the next 10 years. Prog Neurobiol 2011; 95:718-28. [PMID: 22137045 DOI: 10.1016/j.pneurobio.2011.11.008] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Alzheimer's disease (AD) is a fast growing world-wide epidemic. AD is a genetically complex, slowly progressive, and irreversible neurodegenerative disease of the brain. During decades of asymptomatic progression multiple interactive systems, pathways and molecular mechanisms (e.g. protein processing, aberrant signaling, inflammation and immune system, lipid transport, endocytosis, apoptosis, oxidative damage and response to stress, tau pathology, neuron and synapse loss, energy metabolism), contribute to the development of the early clinical prodromal stage with episodic memory deficits and to further decline and loss of general cognitive functioning during the final syndromal dementia stage. The non-mendelian genetically complex "sporadic" AD type is the most common form of dementia affecting people usually over the age of 65. Despite considerable progress of AD research in recent years and evolving paradigm shifts in both pathophysiological concepts as well as in diagnostic criteria fundamental challenges have not yet been resolved. The strong age-related incidence, the recent failure and complete lack of disease-modifying or preventive therapy that may delay onset or substantially affect the pathophysiology of AD, result in an enormous burden posed both on individuals, their families and care givers, and the societies at large, and these call for urgent concerted worldwide measures. Based on the meeting of the German Task Force on Alzheimer's Disease (GTF-AD) in Paris on July 19th 2011, the present position paper provides an overview on the current state and future developments in epidemiology, pathophysiology, disease conceptualization, diagnostic criteria and their use in research and clinical practice, as well as preventive and symptomatic therapeutic approaches. Particular emphasis is placed on a discussion of the different approaches to diagnostics and therapy taken by preventive/public health medicine, methodologically advanced academic research propagating the use of sophisticated biomarkers, and everyday clinical practice focusing on patient-centered care. During the next 10 years, major advances both in early detection as well as in therapy and comprehensive AD care seem mandatory. These still unmet needs call for ever more concerted and focused efforts in research across the world to combat the erupting and as yet uncontrolled epidemic of AD.
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Affiliation(s)
- Harald Hampel
- Department of Psychiatry, Psychosomatic Medicine & Psychotherapy, Goethe University, Frankfurt, Germany.
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Bekris LM, Lutz F, Yu CE. Functional analysis of APOE locus genetic variation implicates regional enhancers in the regulation of both TOMM40 and APOE. J Hum Genet 2011; 57:18-25. [PMID: 22089642 PMCID: PMC3266441 DOI: 10.1038/jhg.2011.123] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Genetic variation within the apolipoprotein E gene (APOE) locus is associated with late-onset Alzheimer's disease risk and quantitative traits as well as apoE expression in multiple tissues. The aim of this investigation was to explore the influence of APOE locus cis-regulatory element enhancer region genetic variation on regional gene promoter activity. Luciferase reporter constructs containing haplotypes of APOE locus gene promoters; APOE, APOC1, and TOMM40, and regional putative enhancers; TOMM40 IVS2-4, TOMM40 IVS6 poly-T, as well as previously described enhancers; ME1, or BCR, were evaluated for their effects on luciferase activity in 3 human cell lines. Results of this investigation demonstrate that in SHSY5Y cells, the APOE promoter is significantly influenced by the TOMM40 IVS2-4 and ME1 and the TOMM40 promoter is significantly influenced by the TOMM40 IVS6 poly-T, ME1 and BCR. In HepG2 cells, theTOMM40 promoter is significantly influenced by all four enhancers, whereas the APOE promoter is not influenced by any of the enhancers. The main novel finding of this investigation was that multiple APOE locus cis-elements influence both APOE and TOMM40 promoter activity according to haplotype and cell type suggesting that a complex transcriptional regulatory structure modulates regional expression.
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Affiliation(s)
- Lynn M Bekris
- Geriatric Research, Education and Clinical Center, VA Puget Sound Health Care System, 1660 South Columbian Way, Seattle, WA 98108, USA..
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TOMM40 poly-T repeat lengths, age of onset and psychosis risk in Alzheimer disease. Neurobiol Aging 2011; 32:2328.e1-9. [PMID: 21820212 DOI: 10.1016/j.neurobiolaging.2011.06.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 06/07/2011] [Accepted: 06/17/2011] [Indexed: 12/26/2022]
Abstract
Apolipoprotein E (APOE) ε4 alleles increase the risk for late-onset Alzheimer disease (LOAD) and decrease the age of onset. Recently, sequencing the APOE region in a small sample of LOAD subjects identified a variable length poly-T repeat sequence in the nearby gene, TOMM40, which may affect age of onset. We genotyped the TOMM40 poly-T repeat using a novel statistical approach to refine the identification of allele length in 892 LOAD subjects and evaluated its effects on age of onset. Because psychosis in LOAD is a heritable phenotype which has shown conflicting associations with APOE genotype, we also evaluated the association of poly-T repeat length with psychosis. Poly-T repeat lengths had a trimodal distribution which differed between APOE genotype groups. After accounting for APOE ε4 there was no association of poly-T repeat length with age of onset. Neither APOE ε4 nor poly-T repeat length was associated with psychosis. Our findings do not support the association of poly-T repeat length with age of onset in LOAD. The clinical implications of this repeat length polymorphism remain to be elucidated.
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45
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Maruszak A, Żekanowski C. Mitochondrial dysfunction and Alzheimer's disease. Prog Neuropsychopharmacol Biol Psychiatry 2011; 35:320-30. [PMID: 20624441 DOI: 10.1016/j.pnpbp.2010.07.004] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 05/31/2010] [Accepted: 07/05/2010] [Indexed: 01/16/2023]
Abstract
To date, one of the most discussed hypotheses for Alzheimer's disease (AD) etiology implicates mitochondrial dysfunction and oxidative stress as one of the primary events in the course of AD. In this review we focus on the role of mitochondria and mitochondrial DNA (mtDNA) variation in AD and discuss the rationale for the involvement of mitochondrial abnormalities in AD pathology. We summarize the current data regarding the proteins involved in mitochondrial function and pathology observed in AD, and discuss the role of somatic mutations and mitochondrial haplogroups in AD development.
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Affiliation(s)
- Aleksandra Maruszak
- Department of Neurodegenerative Disorders, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego 5 Str., 02-106 Warszawa, Poland.
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46
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Praline J, Blasco H, Vourc'h P, Garrigue MA, Gordon PH, Camu W, Corcia P, Andres CR. APOE ε4 allele is associated with an increased risk of bulbar-onset amyotrophic lateral sclerosis in men. Eur J Neurol 2011; 18:1046-52. [PMID: 21251163 DOI: 10.1111/j.1468-1331.2010.03330.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Several association studies have identified possible susceptibility factors for sporadic amyotrophic lateral sclerosis (SALS). Studies on the APOE gene provided conflicting results, especially about the effect on bulbar onset. We assessed the possible role of APOE gene in a large cohort of patients with ALS and matched controls. METHODS The APOE alleles were determined in 1482 patients with SALS and 955 controls and analysed by univariate and multivariate statistics, taking into account gender, site-of-onset and age-at-onset. RESULTS Patients with bulbar onset were more likely to be women [odds ratio (OR)=2.17; 95% CI: 1.74-2.72] and to be older (OR=3.47; 95% CI: 2.58-4.67). The ε4-carriers were more frequent in the bulbar-onset group than in the limb-onset group (OR=1.39 bulbar onset versus limb onset; 95% CI: 1.08-1.80) but this association was observed amongst men (OR=1.78; 95% CI: 1.25-2.53) and not women (OR=1.09; 95% CI: 0.75-1.59). CONCLUSION Our study provides evidence for a contribution of the ε4 allele in the occurrence of bulbar-onset ALS amongst men. We propose that men are normally protected by androgens against bulbar onset and that the ε4 allele inhibits this protection, perhaps by interfering with the androgen pathway.
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Affiliation(s)
- J Praline
- UMR INSERM U930, Université François-Rabelais, Tours Centre SLA, Service de Neurologie et Neurophysiologie Clinique, CHRU de Tours, Tours Cedex 2, France.
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47
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Swerdlow RH. Role and treatment of mitochondrial DNA-related mitochondrial dysfunction in sporadic neurodegenerative diseases. Curr Pharm Des 2011; 17:3356-73. [PMID: 21902672 PMCID: PMC3351798 DOI: 10.2174/138161211798072535] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 08/26/2011] [Indexed: 12/12/2022]
Abstract
Several sporadic neurodegenerative diseases display phenomena that directly or indirectly relate to mitochondrial function. Data suggesting altered mitochondrial function in these diseases could arise from mitochondrial DNA (mtDNA) are reviewed. Approaches for manipulating mitochondrial function and minimizing the downstream consequences of mitochondrial dysfunction are discussed.
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Affiliation(s)
- Russell H Swerdlow
- Department of Neurology, University of Kansas School of Medicine, Kansas City, 66160, USA.
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48
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Porcellini E, Carbone I, Ianni M, Licastro F. Alzheimer's disease gene signature says: beware of brain viral infections. IMMUNITY & AGEING 2010; 7:16. [PMID: 21156047 PMCID: PMC3019140 DOI: 10.1186/1742-4933-7-16] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 12/14/2010] [Indexed: 12/13/2022]
Abstract
Background Recent findings from a genome wide association investigation in a large cohort of patients with Alzheimer's disease (AD) and non demented controls (CTR) showed that a limited set of genes was in a strong association (p > l0-5) with the disease. Presentation of the hypothesis In this report we suggest that the polymorphism association in 8 of these genes is consistent with a non conventional interpretation of AD etiology. Nectin-2 (NC-2), apolipoprotein E (APOE), glycoprotein carcinoembryonic antigen related cell adhesion molecule- 16 (CEACAM-16), B-cell lymphoma-3 (Bcl-3), translocase of outer mitochondrial membrane 40 homolog (T0MM-40), complement receptor-1 (CR-l), APOJ or clusterin and C-type lectin domain A family-16 member (CLEC-16A) result in a genetic signature that might affect individual brain susceptibility to infection by herpes virus family during aging, leading to neuronal loss, inflammation and amyloid deposition. Implications of the hypothesis We hypothesized that such genetic trait may predispose to AD via complex and diverse mechanisms each contributing to an increase of individual susceptibility to brain viral infections
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Affiliation(s)
- Elisa Porcellini
- Department of Experimental Pathology, School of Medicine, University of Bologna Italy.
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Supnet C, Bezprozvanny I. Neuronal calcium signaling, mitochondrial dysfunction, and Alzheimer's disease. J Alzheimers Dis 2010; 20 Suppl 2:S487-98. [PMID: 20413848 PMCID: PMC4996661 DOI: 10.3233/jad-2010-100306] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder among the aged worldwide. AD is characterized by extensive synaptic and neuronal loss that leads to impaired memory and cognitive decline. The cause of AD is not completely understood and no effective therapy has been developed. The accumulation of toxic amyloid-beta42 (Abeta42) peptide oligomers and aggregates in AD brain has been proposed to be primarily responsible for the pathology of the disease, an idea dubbed the 'amyloid hypothesis' of AD etiology. In addition to the increase in Abeta42 levels, disturbances in neuronal calcium (Ca2+) signaling and alterations in expression levels of Ca2+ signaling proteins have been observed in animal models of familial AD and in studies of postmortem brain samples from sporadic AD patients. Based on these data, the 'Ca2+ hypothesis of AD' has been proposed. In particular, familial AD has been linked with enhanced Ca2+ release from the endoplasmic reticulum and elevated cytosolic Ca2+ levels. The augmented cytosolic Ca2+ levels can trigger signaling cascades that affect synaptic stability and function and can be detrimental to neuronal health, such as activation of calcineurin and calpains. Here we review the latest results supporting the 'Ca2+ hypothesis' of AD pathogenesis. We further argue that over time, supranormal cytosolic Ca2+ signaling can impair mitochondrial function in AD neurons. We conclude that inhibitors and stabilizers of neuronal Ca2+ signaling and mitochondrial function may have therapeutic potential for AD treatment. We also discuss latest and planned AD therapeutic trials of agents targeting Ca2+ channels and mitochondria.
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Affiliation(s)
- Charlene Supnet
- Department of Physiology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX
| | - Ilya Bezprozvanny
- Department of Physiology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX
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50
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Abstract
We first proposed the mitochondrial cascade hypothesis of sporadic Alzheimer's disease (AD) in 2004. Our core assumptions were a person's genes determine baseline mitochondrial function and durability, this durability determines how mitochondria change with advancing age, and critical changes in mitochondrial function initiate other pathologies characteristic of AD. Since then several lines of investigation report data consistent with or supportive of our hypothesis. In particular, AD endophenotype studies suggest a strong maternal genetic contribution, and links between mitochondrial function, tau phosphorylation, and amyloid-beta (Abeta) amyloidosis are increasingly recognized. As predicted, AD therapies designed to reduce Abeta thus far have had at best very limited clinical benefits; our hypothesis identifies alternative therapeutic targets. While placing mitochondria at the apex of an AD cascade certainly remains controversial, it is increasingly accepted by the AD research community that mitochondria play an important role in the late-onset forms of the disease. Even if the mitochondrial cascade hypothesis proves incorrect, considering its assumptions could potentially advance our understanding of sporadic, late-onset AD.
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Affiliation(s)
- Russell H Swerdlow
- Departments of Neurology and Molecular and Integrative Physiology, University of Kansas School of Medicine, Kansas City, KS, USA.
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