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Honea RA, Hunt S, Lepping RJ, Vidoni ED, Morris JK, Watts A, Michaelis E, Burns JM, Swerdlow RH. Alzheimer's disease cortical morphological phenotypes are associated with TOMM40'523-APOE haplotypes. Neurobiol Aging 2023; 132:131-144. [PMID: 37804609 PMCID: PMC10763175 DOI: 10.1016/j.neurobiolaging.2023.09.001] [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: 03/10/2023] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 10/09/2023]
Abstract
Both the APOE ε4 and TOMM40 rs10524523 ("523") genes have been associated with risk for Alzheimer's disease (AD) and neuroimaging biomarkers of AD. No studies have investigated the relationship of TOMM40'523-APOE ε4 on the structural complexity of the brain in AD individuals. We quantified brain morphology and multiple cortical attributes in individuals with mild cognitive impairment (MCI) and AD, then tested whether APOE ε4 or TOMM40 poly-T genotypes were related to AD morphological biomarkers in cognitively unimpaired (CU) and MCI/AD individuals. We identified several AD-specific phenotypes in brain morphology and found that TOMM40 poly-T short alleles are associated with early, AD-specific brain morphological differences in healthy aging. We observed decreased cortical thickness, sulcal depth, and fractal dimension in CU individuals with the poly-T short alleles. Moreover, in MCI/AD participants, the APOE ε4 (TOMM40 L) individuals had a higher rate of gene-related morphological markers indicative of AD. Our data suggest that TOMM40'523 is associated with early brain structure variations in the precuneus, temporal, and limbic cortices.
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Affiliation(s)
- Robyn A Honea
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA.
| | - Suzanne Hunt
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA
| | - Rebecca J Lepping
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Hoglund Biomedical Imaging Center, University of Kansas Medical Center, Kansas City, KS, USA; Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA
| | - Eric D Vidoni
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA
| | - Jill K Morris
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA
| | - Amber Watts
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Psychology, University of Kansas, Lawrence, KS, USA
| | - Elias Michaelis
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Pharmacology and Toxicology, University of Kansas, Lawrence, KS, USA
| | - Jeffrey M Burns
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA
| | - Russell H Swerdlow
- University of Kansas Alzheimer's Disease Center, University of Kansas School of Medicine, Kansas City, KS, USA; Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA
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Teubel J, Parr MK. Determination of neurosteroids in human cerebrospinal fluid in the 21st century: A review. J Steroid Biochem Mol Biol 2020; 204:105753. [PMID: 32937199 DOI: 10.1016/j.jsbmb.2020.105753] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/02/2020] [Accepted: 09/07/2020] [Indexed: 12/19/2022]
Abstract
Determination of steroid hormones synthesized by the human body plays an important role in various fields of endocrinology. Neurosteroids (NS) are steroids that are synthesized in the central (CNS) or peripheral nervous system (PNS), which is not only a source but also a target for neurosteroids. They are discussed as possible biomarkers in various cognitive disorders and research interest in this topic raises continuously. Nevertheless, knowledge on functions and metabolism is still limited, although the concept of neurosteroids was already introduced in the 1980s. Until today, the analysis of neurosteroids is truly challenging. The only accessible matrix for investigations of brain metabolism in living human beings is cerebrospinal fluid (CSF), which therefore becomes a very interesting specimen for analysis. However, neurosteroid concentrations are expected to be very low and the available amount of cerebrospinal fluid is limited. Further, high structural similarities of endogenous neurosteroids challenges analysis. Therefore, comprehensive methods, highly selective and sensitive for a large range of concentrations for different steroids in one aliquot are required and under continuous development. Although research has been increasingly intensified, still only few data are available on reference levels of neurosteroids in human cerebrospinal fluid. In this review, published literature of the last twenty years, as a period with relatively contemporary analytical methods, was systematically investigated. Considerations on human cerebrospinal fluid, different analytical approaches, and available data on levels of in analogy to periphery conceivable occurring neurosteroids, including (pro-) gestagens, androgens, corticoids, estrogens, and steroid conjugates, and their interpretation are intensively discussed.
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Affiliation(s)
- Juliane Teubel
- Freie Universität Berlin, Institute of Pharmacy, Königin-Luise-Str. 2+4, 14195 Berlin, Germany
| | - Maria Kristina Parr
- Freie Universität Berlin, Institute of Pharmacy, Königin-Luise-Str. 2+4, 14195 Berlin, Germany.
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3
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Alzheimer's disease pathology explains association between dementia with Lewy bodies and APOE-ε4/TOMM40 long poly-T repeat allele variants. ALZHEIMERS & DEMENTIA-TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2019; 5:814-824. [PMID: 31788537 PMCID: PMC6880091 DOI: 10.1016/j.trci.2019.08.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Introduction The role of TOMM40-APOE 19q13.3 region variants is well documented in Alzheimer's disease (AD) but remains contentious in dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). Methods We dissected genetic profiles within the TOMM40-APOE region in 451 individuals from four European brain banks, including DLB and PDD cases with/without neuropathological evidence of AD-related pathology and healthy controls. Results TOMM40-L/APOE-ε4 alleles were associated with DLB (ORTOMM40-L = 3.61; P value = 3.23 × 10−9; ORAPOE-ε4 = 3.75; P value = 4.90 × 10−10) and earlier age at onset of DLB (HRTOMM40-L = 1.33, P value = .031; HRAPOE-ε4 = 1.46, P value = .004), but not with PDD. The TOMM40-L/APOE-ε4 effect was most pronounced in DLB individuals with concomitant AD pathology (ORTOMM40-L = 4.40, P value = 1.15 × 10−6; ORAPOE-ε4 = 5.65, P value = 2.97 × 10−8) but was not significant in DLB without AD. Meta-analyses combining all APOE-ε4 data in DLB confirmed our findings (ORDLB = 2.93, P value = 3.78 × 10−99; ORDLB+AD = 5.36, P value = 1.56 × 10−47). Discussion APOE-ε4/TOMM40-L alleles increase susceptibility and risk of earlier DLB onset, an effect explained by concomitant AD-related pathology. These findings have important implications in future drug discovery and development efforts in DLB.
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Chiba-Falek O, Gottschalk WK, Lutz MW. The effects of the TOMM40 poly-T alleles on Alzheimer's disease phenotypes. Alzheimers Dement 2018. [PMID: 29524426 DOI: 10.1016/j.jalz.2018.01.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The TOMM40 poly-T is a polymorphism in intron 6 of the TOMM40 gene, which is adjacent to and in linkage disequilibrium with APOE. Roses et al. identified the association between the length of TOMM40 poly-T with the risk and age of onset of late-onset Alzheimer's disease (LOAD). Following the original discovery, additional studies found associations between the TOMM40 poly-T and LOAD-related phenotypes independent of APOE genotypes, while others did not replicate these associations. Furthermore, the identity of the TOMM40 poly-T risk allele has been controversial between different LOAD-related phenotypes. Here, we propose a framework to address the conflicting findings with respect to the TOMM40 poly-T allele associations with LOAD phenotypes and their functional effects. The framework is used to interpret previous studies as means to gain insights regarding the nature of the risk allele, very long versus short. We suggest that the identity of the TOMM40 poly-T risk allele depends on the phenotype being evaluated, the ages of the study subjects at the time of assessment, and the context of the APOE genotypes. In concluding remarks, we outline future studies that will inform the mechanistic interpretation of the genetic data.
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Affiliation(s)
- Ornit Chiba-Falek
- Department of Neurology, Duke University Medical Center, Durham, NC, USA; Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, USA.
| | | | - Michael W Lutz
- Department of Neurology, Duke University Medical Center, Durham, NC, USA
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5
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Dhillon H, Singh S. Role of Apolipoprotein E in the tangled mystery of pain. Med Hypotheses 2018; 114:58-64. [PMID: 29602467 DOI: 10.1016/j.mehy.2018.02.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 01/12/2018] [Accepted: 02/25/2018] [Indexed: 01/12/2023]
Abstract
Pain is one of the common and debilitating health manifestations associated with the majority of diseased conditions, thus making it a serious health concern worldwide. While trying to decipher the cryptic mechanism of pain in hope to provide better gene-based therapeutics, researchers have concluded pain to be of multigenic origin making it hard to cure. Apolipoprotein E is a protein coded by APOE gene containing 4 exons, located on chromosome 19q13.2. It is among the key regulators of various crucial body functions such as lipid transport, apoptosis, vitamin k pathway, and cognition, hence, it is highly suspected to play a pivotal role in the nociception process. However, very few studies have tried and succeeded to find a direct involvement of APOE in pain processing. The current article attempts to throw light on some of the major clinical research findings which strengthen the hypothesis stating that apolipoprotein E has a concealed yet deeply embedded association with the pain regulating pathways, through several underlying physiological, biochemical and neurological processes, that in turn, decide the fate of pain sensation in a complex manner.
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Affiliation(s)
- Harjot Dhillon
- Mata Lajjiawatti Jain Memorial Nursing Institute, Raikot, Punjab, India.
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6
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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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7
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Lyall DM, Muñoz Maniega S, Harris SE, Bastin ME, Murray C, Lutz MW, Saunders AM, Roses AD, Valdés Hernández MDC, Royle NA, Starr JM, Porteous DJ, Deary IJ, Wardlaw JM. APOE/TOMM40 genetic loci, white matter hyperintensities, and cerebral microbleeds. Int J Stroke 2015; 10:1297-300. [PMID: 26310205 PMCID: PMC4950052 DOI: 10.1111/ijs.12615] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 06/30/2015] [Indexed: 11/29/2022]
Abstract
Background Two markers of cerebral small vessel disease are white matter hyperintensities and cerebral microbleeds, which commonly occur in people with Alzheimer's disease. Aim and/or hypothesis To test for independent associations between two Alzheimer's disease‐susceptibility gene loci – APOE ε and the TOMM40 ‘523’ poly‐T repeat – and white matter hyperintensities/cerebral microbleed burden in community‐dwelling older adults. Methods Participants in the Lothian Birth Cohort 1936 underwent genotyping for APOE ε and TOMM40 523, and detailed structural brain magnetic resonance imaging at a mean age of 72·70 years (standard deviation = 0·7; range = 71–74). Results No significant effects of APOE ε or TOMM40 523 genotypes on white matter hyperintensities or cerebral microbleed burden were found amongst 624 participants. Conclusions Lack of association between two Alzheimer's disease susceptibility gene loci and markers of cerebral small vessel disease may reflect the relative health of this population compared with those in other studies in the literature.
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Affiliation(s)
- Donald M Lyall
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK.,Department of Psychology, University of Edinburgh, Edinburgh, UK.,Medical Genetics Section, University of Edinburgh Centre for Genomics and Experimental Medicine and MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - Susana Muñoz Maniega
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK.,Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Sarah E Harris
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Medical Genetics Section, University of Edinburgh Centre for Genomics and Experimental Medicine and MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - Mark E Bastin
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK.,Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Catherine Murray
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Michael W Lutz
- Joseph & Kathleen Bryan Alzheimer's Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Ann M Saunders
- Joseph & Kathleen Bryan Alzheimer's Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, NC, USA
| | - Allen D Roses
- Joseph & Kathleen Bryan Alzheimer's Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, NC, USA.,Zinfandel Pharmaceuticals, Inc., Durham, NC, USA
| | - Maria del C Valdés Hernández
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK.,Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Natalie A Royle
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK.,Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - John M Starr
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Alzheimer Scotland Dementia Research Centre, Edinburgh, UK
| | - David J Porteous
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Medical Genetics Section, University of Edinburgh Centre for Genomics and Experimental Medicine and MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - Ian J Deary
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Joanna M Wardlaw
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK.,Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK.,Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
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8
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Bruno D, Grothe MJ, Nierenberg J, Zetterberg H, Blennow K, Teipel SJ, Pomara N. A study on the specificity of the association between hippocampal volume and delayed primacy performance in cognitively intact elderly individuals. Neuropsychologia 2015; 69:1-8. [PMID: 25613646 DOI: 10.1016/j.neuropsychologia.2015.01.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 01/15/2015] [Accepted: 01/17/2015] [Indexed: 11/19/2022]
Abstract
Delayed recall at the primacy position (first few items on a list) has been shown to predict cognitive decline in cognitively intact elderly participants, with poorer delayed primacy performance associated with more pronounced generalized cognitive decline during follow-up. We have previously suggested that this association is due to delayed primacy performance indexing memory consolidation, which in turn is thought to depend upon hippocampal function. Here, we test the hypothesis that hippocampal size is associated with delayed primacy performance in cognitively intact elderly individuals. Data were analyzed from a group (N=81) of cognitively intact participants, aged 60 or above. Serial position performance was measured with the Buschke selective reminding test (BSRT). Hippocampal size was automatically measured via MRI, and unbiased voxel-based analyses were also conducted to explore further regional specificity of memory performance. We conducted regression analyses of hippocampus volumes on serial position performance; other predictors included age, family history of Alzheimer's disease (AD), APOE ε4 status, education, and total intracranial volume. Our results collectively suggest that there is a preferential association between hippocampal volume and delayed primacy performance. These findings are consistent with the hypothesis that delayed primacy consolidation is associated with hippocampal size, and shed light on the relationship between delayed primacy performance and generalized cognitive decline in cognitively intact individuals, suggesting that delayed primacy consolidation may serve as a sensitive marker of hippocampal health in these individuals.
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Affiliation(s)
- Davide Bruno
- Department of Psychology, Liverpool Hope University, Hope Park, Liverpool L16 9JD, UK.
| | - Michel J Grothe
- German Center for Neurodegenerative Diseases (DZNE) - Rostock/Greifswald, Rostock, Germany
| | - Jay Nierenberg
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Department of Psychiatry, School of Medicine, New York University, New York City, NY, USA
| | - Henrik Zetterberg
- Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Mölndal, Sweden; UCL Institute of Neurology, London, UK
| | - Kaj Blennow
- Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Mölndal, Sweden
| | - Stefan J Teipel
- German Center for Neurodegenerative Diseases (DZNE) - Rostock/Greifswald, Rostock, Germany; Department of Psychosomatic Medicine, University of Rostock, Rostock, Germany
| | - Nunzio Pomara
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Department of Psychiatry, School of Medicine, New York University, New York City, NY, USA
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9
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Du X, Pang TY. Is Dysregulation of the HPA-Axis a Core Pathophysiology Mediating Co-Morbid Depression in Neurodegenerative Diseases? Front Psychiatry 2015; 6:32. [PMID: 25806005 PMCID: PMC4353372 DOI: 10.3389/fpsyt.2015.00032] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/16/2015] [Indexed: 01/19/2023] Open
Abstract
There is increasing evidence of prodromal manifestation of neuropsychiatric symptoms in a variety of neurodegenerative diseases such as Parkinson's disease (PD) and Huntington's disease (HD). These affective symptoms may be observed many years before the core diagnostic symptoms of the neurological condition. It is becoming more apparent that depression is a significant modifying factor of the trajectory of disease progression and even treatment outcomes. It is therefore crucial that we understand the potential pathophysiologies related to the primary condition, which could contribute to the development of depression. The hypothalamic-pituitary-adrenal (HPA)-axis is a key neuroendocrine signaling system involved in physiological homeostasis and stress response. Disturbances of this system lead to severe hormonal imbalances, and the majority of such patients also present with behavioral deficits and/or mood disorders. Dysregulation of the HPA-axis is also strongly implicated in the pathology of major depressive disorder. Consistent with this, antidepressant drugs, such as the selective serotonin reuptake inhibitors have been shown to alter HPA-axis activity. In this review, we will summarize the current state of knowledge regarding HPA-axis pathology in Alzheimer's, PD and HD, differentiating between prodromal and later stages of disease progression when evidence is available. Both clinical and preclinical evidence will be examined, but we highlight animal model studies as being particularly useful for uncovering novel mechanisms of pathology related to co-morbid mood disorders. Finally, we purpose utilizing the preclinical evidence to better inform prospective, intervention studies.
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Affiliation(s)
- Xin Du
- Mental Health Division, Florey Institute of Neuroscience and Mental Health, University of Melbourne , Melbourne, VIC , Australia
| | - Terence Y Pang
- Behavioural Neurosciences Division, Florey Institute of Neuroscience and Mental Health, University of Melbourne , Melbourne, VIC , Australia
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10
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Linnertz C, Anderson L, Gottschalk W, Crenshaw D, Lutz MW, Allen J, Saith S, Mihovilovic M, Burke JR, Welsh-Bohmer KA, Roses AD, Chiba-Falek O. The cis-regulatory effect of an Alzheimer's disease-associated poly-T locus on expression of TOMM40 and apolipoprotein E genes. Alzheimers Dement 2014; 10:541-51. [PMID: 24439168 PMCID: PMC4098029 DOI: 10.1016/j.jalz.2013.08.280] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 05/13/2013] [Accepted: 08/06/2013] [Indexed: 12/19/2022]
Abstract
BACKGROUND We investigated the genomic region spanning the Translocase of the Outer Mitochondrial Membrane 40-kD (TOMM40) and Apolipoprotein E (APOE) genes, that has been associated with the risk and age of onset of late-onset Alzheimer's disease (LOAD) to determine whether a highly polymorphic, intronic poly-T within this region (rs10524523; hereafter, 523) affects expression of the APOE and TOMM40 genes. Alleles of this locus are classified as S, short; L, long; and VL, very long based on the number of T residues. METHODS We evaluated differences in APOE messenger RNA (mRNA) and TOMM40 mRNA levels as a function of the 523 genotype in two brain regions from APOE ε3/ε3 white autopsy-confirmed LOAD cases and normal controls. We further investigated the effect of the 523 locus in its native genomic context using a luciferase expression system. RESULTS The expression of both genes was significantly increased with disease. Mean expression of APOE and TOMM40 mRNA levels were higher in VL homozygotes compared with S homozygotes in the temporal and occipital cortexes from normal and LOAD cases. Results of a luciferase reporter system were consistent with the human brain mRNA analysis; the 523 VL poly-T resulted in significantly higher expression than the S poly-T. Although the effect of poly-T length on reporter expression was the same in HepG2 hepatoma and SH-SY5Y neuroblastoma cells, the magnitude of the effect was greater in the neuroblastoma than in the hepatoma cells, which implies tissue-specific modulation of the 523 poly-T. CONCLUSIONS These results suggest that the 523 locus may contribute to LOAD susceptibility by modulating the expression of TOMM40 and/or APOE transcription.
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Affiliation(s)
- Colton Linnertz
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Lauren Anderson
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - William Gottschalk
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA; Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA
| | - Donna Crenshaw
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA; Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA
| | - Michael W Lutz
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA; Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA
| | - Jawara Allen
- Institute for Genome Sciences & Policy, Duke University Medical Center, Durham, NC, USA
| | - Sunita Saith
- Institute for Genome Sciences & Policy, Duke University Medical Center, Durham, NC, USA
| | - Mirta Mihovilovic
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - James R Burke
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA; Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA
| | - Kathleen A Welsh-Bohmer
- Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA
| | - Allen D Roses
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA; Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA; Zinfandel Pharmaceuticals, Chapel Hill, NC, USA
| | - Ornit Chiba-Falek
- Division of Neurology at the Department of Medicine, Duke University Medical Center, Durham, NC, USA; Division of Neurology, Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center, Durham, NC, USA; Institute for Genome Sciences & Policy, Duke University Medical Center, Durham, NC, USA.
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11
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Lyall DM, Harris SE, Bastin ME, Muñoz Maniega S, Murray C, Lutz MW, Saunders AM, Roses AD, Valdés Hernández MDC, Royle NA, Starr JM, Porteous DJ, Wardlaw JM, Deary IJ. Alzheimer's disease susceptibility genes APOE and TOMM40, and brain white matter integrity in the Lothian Birth Cohort 1936. Neurobiol Aging 2014; 35:1513.e25-33. [PMID: 24508314 PMCID: PMC3969262 DOI: 10.1016/j.neurobiolaging.2014.01.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 12/02/2013] [Accepted: 01/04/2014] [Indexed: 12/14/2022]
Abstract
Apolipoprotein E (APOE) ε genotype has previously been significantly associated with cognitive, brain imaging, and Alzheimer's disease-related phenotypes (e.g., age of onset). In the TOMM40 gene, the rs10524523 ("523") variable length poly-T repeat polymorphism has more recently been associated with similar ph/enotypes, although the allelic directions of these associations have varied between initial reports. Using diffusion magnetic resonance imaging tractography, the present study aimed to investigate whether there are independent effects of apolipoprotein E (APOE) and TOMM40 genotypes on human brain white matter integrity in a community-dwelling sample of older adults, the Lothian Birth Cohort 1936 (mean age = 72.70 years, standard deviation = 0.74, N approximately = 640-650; for most analyses). Some nominally significant effects were observed (i.e., covariate-adjusted differences between genotype groups at p < 0.05). For APOE, deleterious effects of ε4 "risk" allele presence (vs. absence) were found in the right ventral cingulum and left inferior longitudinal fasciculus. To test for biologically independent effects of the TOMM40 523 repeat, participants were stratified into APOE genotype subgroups, so that any significant effects could not be attributed to APOE variation. In participants with the APOE ε3/ε4 genotype, effects of TOMM40 523 status were found in the left uncinate fasciculus, left rostral cingulum, left ventral cingulum, and a general factor of white matter integrity. In all 4 of these tractography measures, carriers of the TOMM40 523 "short" allele showed lower white matter integrity when compared with carriers of the "long" and "very-long" alleles. Most of these effects survived correction for childhood intelligence test scores and vascular disease history, though only the effect of TOMM40 523 on the left ventral cingulum integrity survived correction for false discovery rate. The effects of APOE in this older population are more specific and restricted compared with those reported in previous studies, and the effects of TOMM40 on white matter integrity appear to be novel, although replication is required in large independent samples.
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Affiliation(s)
- Donald M Lyall
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK; Department of Psychology, University of Edinburgh, Edinburgh, UK; Medical Genetics Section, University of Edinburgh Centre for Genomics and Experimental Medicine, Western General Hospital, Edinburgh, UK; MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - Sarah E Harris
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Medical Genetics Section, University of Edinburgh Centre for Genomics and Experimental Medicine, Western General Hospital, Edinburgh, UK; MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - Mark E Bastin
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK; Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Susana Muñoz Maniega
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK; Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Catherine Murray
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Michael W Lutz
- Department of Neurology, Joseph & Kathleen Bryan Alzheimer's Disease Research Center, Durham, NC, USA; Duke University Medical Center, Durham, NC, USA
| | - Ann M Saunders
- Department of Neurology, Joseph & Kathleen Bryan Alzheimer's Disease Research Center, Durham, NC, USA
| | - Allen D Roses
- Department of Neurology, Joseph & Kathleen Bryan Alzheimer's Disease Research Center, Durham, NC, USA; Duke University Medical Center, Durham, NC, USA; Zinfandel Pharmaceuticals, Inc, Durham, NC, USA
| | - Maria del C Valdés Hernández
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK; Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Natalie A Royle
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK; Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - John M Starr
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Alzheimer Scotland Dementia Research Centre, University of Edinburgh, Edinburgh, UK
| | - David J Porteous
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Medical Genetics Section, University of Edinburgh Centre for Genomics and Experimental Medicine, Western General Hospital, Edinburgh, UK; MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - Joanna M Wardlaw
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, UK; Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, UK
| | - Ian J Deary
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK; Department of Psychology, University of Edinburgh, Edinburgh, UK.
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Gottschalk WK, Lutz MW, He YT, Saunders AM, Burns DK, Roses AD, Chiba-Falek O. The Broad Impact of TOM40 on Neurodegenerative Diseases in Aging. ACTA ACUST UNITED AC 2014; 1. [PMID: 25745640 DOI: 10.13188/2376-922x.1000003] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Mitochondrial dysfunction is an important factor in the pathogenesis of age-related diseases, including neurodegenerative diseases like Alzheimer's and Parkinson's spectrum disorders. A polymorphism in Translocase of the Outer Mitochondrial Membrane - 40 kD (TOMM40) is associated with risk and age-of onset of late-onset AD, and is the only nuclear- encoded gene identified in genetic studies to date that presumably contributes to LOAD-related mitochondria dysfunction. In this review, we describe the TOM40-mediated mitochondrial protein import mechanism, and discuss the evidence linking TOM40 with Alzheimer's (AD) and Parkinson's (PD) diseases. All but 36 of the >~1,500 mitochondrial proteins are encoded by the nucleus and are synthesized on cytoplasmic ribosomes, and most of these are imported into mitochondria through the TOM complex, of which TOM40 is the central pore, mediating communication between the cytoplasm and the mitochondrial interior. APP enters and obstructs the TOM40 pore, inhibiting import of OXPHOS-related proteins and disrupting the mitochondrial redox balance. Other pathogenic proteins, such as Aβ and alpha-synuclein, readily pass through the pore and cause toxic effects by directly inhibiting mitochondrial enzymes. Healthy mitochondria normally import and degrade the PD-related protein Pink1, but Pink1 exits mitochondria if the membrane potential collapses and initiates Parkin-mediated mitophagy. Under normal circumstances, this process helps clear dysfunctional mitochondria and contributes to cellular health, but PINK1 mutations associated with PD exit mitochondria with intact membrane potentials, disrupting mitochondrial dynamics, leading to pathology. Thus, TOM40 plays a central role in the mitochondrial dysfunction that underlies age-related neurodegenerative diseases. Learning about the factors that control TOM40 levels and activity, and how TOM40, specifically, and the TOM complex, generally, interacts with potentially pathogenic proteins, will provide deeper insights to AD and PD pathogenesis, and possibly new targets for preventative and/or therapeutic treatments.
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Affiliation(s)
- William K Gottschalk
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA ; Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA
| | - Michael W Lutz
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA ; Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA
| | - Yu Ting He
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ann M Saunders
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA ; Zinfandel Pharmaceuticals, Chapel Hill, NC, USA
| | | | - Allen D Roses
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA ; Joseph and Kathleen Bryan Alzheimer's Disease Research Center, 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 ; Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA
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13
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Lyall DM, Royle NA, Harris SE, Bastin ME, Maniega SM, Murray C, Lutz MW, Saunders AM, Roses AD, del Valdés Hernández MC, Starr JM, Porteous DJ, Wardlaw JM, Deary IJ. Alzheimer's disease susceptibility genes APOE and TOMM40, and hippocampal volumes in the Lothian birth cohort 1936. PLoS One 2013; 8:e80513. [PMID: 24260406 PMCID: PMC3829876 DOI: 10.1371/journal.pone.0080513] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 10/04/2013] [Indexed: 12/12/2022] Open
Abstract
The APOE ε and TOMM40 rs10524523 (‘523’) variable length poly-T repeat gene loci have been significantly and independently associated with Alzheimer’s disease (AD) related phenotypes such as age of clinical onset. Hippocampal atrophy has been significantly associated with memory impairment, a characteristic of AD. The current study aimed to test for independent effects of APOE ε and TOMM40 ‘523’ genotypes on hippocampal volumes as assessed by brain structural MRI in a relatively large sample of community-dwelling older adults. As part of a longitudinal study of cognitive ageing, participants in the Lothian Birth Cohort 1936 underwent genotyping for APOE ε2/ε3/ε4 status and TOMM40 ‘523’ poly-T repeat length, and detailed structural brain MRI at a mean age of 72.7 years (standard deviation = 0.7, N range = 624 to 636). No significant effects of APOE ε or TOMM40 523 genotype were found on hippocampal volumes when analysed raw, or when adjusted for either intracranial or total brain tissue volumes. In summary, in a large community-dwelling sample of older adults, we found no effects of APOE ε or TOMM40 523 genotypes on hippocampal volumes. This is discrepant with some previous reports of significant association between APOE and left/right hippocampal volumes, and instead echoes other reports that found no association. Previous significant findings may partly reflect type 1 error. Future studies should carefully consider: 1) their specific techniques in adjusting for brain size; 2) assessing more detailed sub-divisions of the hippocampal formation; and 3) testing whether significant APOE-hippocampal associations are independent of generalised brain atrophy.
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Affiliation(s)
- Donald M. Lyall
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Department of Psychology, University of Edinburgh, Edinburgh, United Kingdom
- Medical Genetics Section, Centre for Genomics and Experimental Medicine and MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Natalie A. Royle
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Sarah E. Harris
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Medical Genetics Section, Centre for Genomics and Experimental Medicine and MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Mark E. Bastin
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Susana Muñoz Maniega
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Catherine Murray
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Department of Psychology, University of Edinburgh, Edinburgh, United Kingdom
| | - Michael W. Lutz
- Joseph & Kathleen Bryan Alzheimer’s Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Ann M. Saunders
- Joseph & Kathleen Bryan Alzheimer’s Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Allen D. Roses
- Joseph & Kathleen Bryan Alzheimer’s Disease Research Center, Department of Neurology, Duke University Medical Center, Durham, North Carolina, United States of America
- Zinfandel Pharmaceuticals, Inc., Durham, North Carolina, United States of America
| | - Maria C. del Valdés Hernández
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - John M. Starr
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Alzheimer Scotland Dementia Research Centre, University of Edinburgh, Edinburgh, United Kingdom
| | - David. J. Porteous
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Medical Genetics Section, Centre for Genomics and Experimental Medicine and MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Joanna M. Wardlaw
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Division of Neuroimaging Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Ian J. Deary
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom
- Department of Psychology, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
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14
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Soares HD, Potter WZ, Pickering E, Kuhn M, Immermann FW, Shera DM, Ferm M, Dean RA, Simon AJ, Swenson F, Siuciak JA, Kaplow J, Thambisetty M, Zagouras P, Koroshetz WJ, Wan HI, Trojanowski JQ, Shaw LM. Plasma biomarkers associated with the apolipoprotein E genotype and Alzheimer disease. ACTA ACUST UNITED AC 2013; 69:1310-7. [PMID: 22801723 DOI: 10.1001/archneurol.2012.1070] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND A blood-based test that could be used as a screen for Alzheimer disease (AD) may enable early intervention and better access to treatment. OBJECTIVE To apply a multiplex immunoassay panel to identify plasma biomarkers of AD using plasma samples from the Alzheimer's Disease Neuroimaging Initiative cohort. DESIGN Cohort study. SETTING The Biomarkers Consortium Alzheimer's Disease Plasma Proteomics Project. PARTICIPANTS Plasma samples at baseline and at 1 year were analyzed from 396 (345 at 1 year) patients with mild cognitive impairment, 112 (97 at 1 year) patients with AD, and 58 (54 at 1 year) healthy control subjects. MAIN OUTCOME MEASURES Multivariate and univariate statistical analyses were used to examine differences across diagnostic groups and relative to the apolipoprotein E (ApoE) genotype. RESULTS Increased levels of eotaxin 3, pancreatic polypeptide, and N-terminal protein B-type brain natriuretic peptide were observed in patients, confirming similar changes reported in cerebrospinal fluid samples of patients with AD and MCI. Increases in tenascin C levels and decreases in IgM and ApoE levels were also observed. All participants with Apo ε3/ε4 or ε4/ε4 alleles showed a distinct biochemical profile characterized by low C-reactive protein and ApoE levels and by high cortisol, interleukin 13, apolipoprotein B, and gamma interferon levels. The use of plasma biomarkers improved specificity in differentiating patients with AD from controls, and ApoE plasma levels were lowest in patients whose mild cognitive impairment had progressed to dementia. CONCLUSIONS Plasma biomarker results confirm cerebrospinal fluid studies reporting increased levels of pancreatic polypeptide and N-terminal protein B-type brain natriuretic peptide in patients with AD and mild cognitive impairment. Incorporation of plasma biomarkers yielded high sensitivity with improved specificity, supporting their usefulness as a screening tool. The ApoE genotype was associated with a unique biochemical profile irrespective of diagnosis, highlighting the importance of genotype on blood protein profiles.
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Bruno D, Pomara N, Nierenberg J, Ritchie JC, Lutz MW, Zetterberg H, Blennow K. Levels of cerebrospinal fluid neurofilament light protein in healthy elderly vary as a function of TOMM40 variants. Exp Gerontol 2011; 47:347-52. [PMID: 21983493 DOI: 10.1016/j.exger.2011.09.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 09/21/2011] [Accepted: 09/22/2011] [Indexed: 11/29/2022]
Abstract
Neurofilament light (NFL) proteins in cerebrospinal fluid (CSF) are a marker of neuronal damage, especially subcortical axonal injury and white matter disease. Subjects with Alzheimer's disease (AD) have shown elevated levels of CSF NFL as compared to controls. However, the presence of the APOE ε4 allele, an established risk factor for AD, was not found to associate with higher CSF NFL concentrations. We examined whether TOMM40 variants, which have been reported to influence age of onset of AD and are in linkage disequilibrium with APOE, have an effect on CSF NFL levels, in 47 healthy, cognitively intact individuals with or without APOE ε4. Our results show that the presence of APOE ε4 alone does not affect CSF NFL levels significantly; however APOE and TOMM40 appear to interact. Subjects with APOE ε4 have higher CSF NFL levels than non-ε4 carriers, only when they do not carry a short poly-T variant of TOMM40, which is associated with later age of onset of AD, and may act as protective against the dose effect of ε4.
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Affiliation(s)
- Davide Bruno
- Nathan Kline Institute, Orangeburg, NY 10962, USA.
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