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Kac PR, González-Ortiz F, Emeršič A, Dulewicz M, Koutarapu S, Turton M, An Y, Smirnov D, Kulczyńska-Przybik A, Varma VR, Ashton NJ, Montoliu-Gaya L, Camporesi E, Winkel I, Paradowski B, Moghekar A, Troncoso JC, Lashley T, Brinkmalm G, Resnick SM, Mroczko B, Kvartsberg H, Gregorič Kramberger M, Hanrieder J, Čučnik S, Harrison P, Zetterberg H, Lewczuk P, Thambisetty M, Rot U, Galasko D, Blennow K, Karikari TK. Plasma p-tau212 antemortem diagnostic performance and prediction of autopsy verification of Alzheimer's disease neuropathology. Nat Commun 2024; 15:2615. [PMID: 38521766 PMCID: PMC10960791 DOI: 10.1038/s41467-024-46876-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 03/04/2024] [Indexed: 03/25/2024] Open
Abstract
Blood phosphorylated tau (p-tau) biomarkers, including p-tau217, show high associations with Alzheimer's disease (AD) neuropathologic change and clinical stage. Certain plasma p-tau217 assays recognize tau forms phosphorylated additionally at threonine-212, but the contribution of p-tau212 alone to AD is unknown. We developed a blood-based immunoassay that is specific to p-tau212 without cross-reactivity to p-tau217. Here, we examined the diagnostic utility of plasma p-tau212. In five cohorts (n = 388 participants), plasma p-tau212 showed high performances for AD diagnosis and for the detection of both amyloid and tau pathology, including at autopsy as well as in memory clinic populations. The diagnostic accuracy and fold changes of plasma p-tau212 were similar to those for p-tau217 but higher than p-tau181 and p-tau231. Immunofluorescent staining of brain tissue slices showed prominent p-tau212 reactivity in neurofibrillary tangles that co-localized with p-tau217 and p-tau202/205. These findings support plasma p-tau212 as a peripherally accessible biomarker of AD pathophysiology.
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Grants
- R01 AG075336 NIA NIH HHS
- R01 AG078796 NIA NIH HHS
- R01 AG083874 NIA NIH HHS
- R01 AG072641 NIA NIH HHS
- R01 AG068398 NIA NIH HHS
- R21 AG078538 NIA NIH HHS
- R01 MH108509 NIMH NIH HHS
- RF1 AG025516 NIA NIH HHS
- P30 AG066468 NIA NIH HHS
- R01 AG073267 NIA NIH HHS
- P01 AG025204 NIA NIH HHS
- #AARF-21-850325 Alzheimer's Association
- R01 MH121619 NIMH NIH HHS
- R37 AG023651 NIA NIH HHS
- R21 AG080705 NIA NIH HHS
- U24 AG082930 NIA NIH HHS
- RF1 AG052525 NIA NIH HHS
- R01 AG053952 NIA NIH HHS
- Demensförbundet (Dementia Association)
- Anna Lisa and Brother Björnsson’s Foundation
- BrightFocus Foundation (BrightFocus)
- Alzheimerfonden
- the Swedish Dementia Foundation, Gun and Bertil Stohnes Foundation, Åhlén-stifelsen, and Gamla Tjänarinnor Foundation.
- Vetenskapsrådet (Swedish Research Council)
- Alzheimer’s Drug Discovery Foundation (ADDF)
- EC | Horizon 2020 Framework Programme (EU Framework Programme for Research and Innovation H2020)
- EU Joint Programme – Neurodegenerative Disease Research (Programi i Përbashkët i BE-së për Kërkimet mbi Sëmundjet Neuro-degjeneruese)
- Swedish State Support for Clinical Research (#ALFGBG-71320), the AD Strategic Fund and the Alzheimer’s Association (#ADSF-21-831376-C, #ADSF-21-831381-C, and #ADSF-21-831377-C) the Bluefield Project, the Olav Thon Foundation, the Erling-Persson Family Foundation, Hjärnfonden, Sweden (#FO2022-0270), the National Institute for Health and Care Research University College London Hospitals Biomedical Research Centre, and the UK Dementia Research Institute at UCL (UKDRI-1003)
- the Swedish Alzheimer Foundation (#AF-930351, #AF-939721 and #AF-968270), Hjärnfonden, Sweden (#FO2017-0243 and #ALZ2022-0006), the Swedish state under the agreement between the Swedish government and the County Councils, the ALF-agreement (#ALFGBG-715986 and #ALFGBG-965240), the National Institute of Health (NIH), USA, (grant #1R01AG068398-01) the Alzheimer’s Association 2021 Zenith Award (ZEN-21-848495).
- Alzheimer’s Association
- National Institute of Health (NIH) - (R01 AG083874-01, U24 AG082930-01 1 RF1 AG052525-01A1, 5 P30 AG066468-04, 5 R01 AG053952-05, 3 R01 MH121619-04S1, 5 R37 AG023651-18, 2 RF1 AG025516-12A1, 5 R01 AG073267-02, 2 R01 MH108509-06, 5 R01 AG075336-02, 5 R01 AG072641-02, 2 P01 AG025204-16) the Swedish Alzheimer Foundation (Alzheimerfonden), the Aina (Ann) Wallströms and Mary-Ann Sjöbloms stiftelsen, and the Emil och Wera Cornells stiftelsen.
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Affiliation(s)
- Przemysław R Kac
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden.
| | - Fernando González-Ortiz
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, 431 80, Sweden
| | - Andreja Emeršič
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, 1000, Slovenia
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
| | - Maciej Dulewicz
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
| | - Srinivas Koutarapu
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
| | | | - Yang An
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Denis Smirnov
- Department of Neurosciences, University of California, San Diego, CA, 92161, USA
| | | | - Vijay R Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Nicholas J Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Department of Old Age Psychiatry, King's College London, London, SE5 8AF, UK
- Centre for Age-Related Medicine, Stavanger University Hospital, 4011, Stavanger, Norway
- South London & Maudsley NHS Foundation, NIHR Biomedical Research Centre for Mental Health & Biomedical Research Unit for Dementia, SE5 8AF, London, UK
| | - Laia Montoliu-Gaya
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
| | - Elena Camporesi
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
| | - Izabela Winkel
- Dementia Disorders Center, Medical University of Wrocław, 59-330, Ścinawa, Poland
| | - Bogusław Paradowski
- Department of Neurology, Medical University of Wrocław, 50-556, Wrocław, Poland
| | - Abhay Moghekar
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Juan C Troncoso
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
- Department of Pathology, John Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Tammaryn Lashley
- Department of Neurodegenerative diseases, UCL Queen Square Institute of Neurology, WC1N 1PJ, London, UK
| | - Gunnar Brinkmalm
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
| | - Susan M Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Barbara Mroczko
- Department of Neurodegeneration Diagnostics, Medical University of Białystok, Białystok, 15-269, Poland
| | - Hlin Kvartsberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, 431 80, Sweden
| | - Milica Gregorič Kramberger
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, 1000, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, 141 52, Huddinge, Sweden
| | - Jörg Hanrieder
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Department of Neurodegenerative Disease, Dementia Research Centre, UCL Institute of Neurology, Queen Square, London, WC1E 6BT, UK
| | - Saša Čučnik
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, 1000, Slovenia
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
- Department of Rheumatology, University Medical Center Ljubljana, Ljubljana, Slovenia
| | | | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, 431 80, Sweden
- Department of Neurodegenerative Disease, Dementia Research Centre, UCL Institute of Neurology, Queen Square, London, WC1E 6BT, UK
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
- Hong Kong Center for Neurodegenerative Diseases, HKCeND, Hong Kong, 1512-1518, China
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Piotr Lewczuk
- Department of Neurodegeneration Diagnostics, Medical University of Białystok, Białystok, 15-269, Poland
- Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen, and Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Uroš Rot
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, 1000, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Douglas Galasko
- Department of Neurosciences, University of California, San Diego, CA, 92161, USA
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, 431 80, Sweden
| | - Thomas K Karikari
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, 431 80, Sweden
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
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2
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Varma VR, An Y, Kac PR, Bilgel M, Moghekar A, Loeffler T, Amschl D, Troncoso J, Blennow K, Zetterberg H, Ashton NJ, Resnick SM, Thambisetty M. Longitudinal progression of blood biomarkers reveals a key role of astrocyte reactivity in preclinical Alzheimer's disease. medRxiv 2024:2024.01.25.24301779. [PMID: 38343809 PMCID: PMC10854357 DOI: 10.1101/2024.01.25.24301779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/26/2024]
Abstract
Defining the progression of blood biomarkers of Alzheimer's disease (AD) is essential for targeting treatments in patients most likely to benefit from early intervention. We delineated the temporal ordering of blood biomarkers a decade prior to the onset of AD symptoms in participants in the Baltimore Longitudinal Study of Aging. We show that increased astrocyte reactivity, assessed by elevated glial fibrillary acidic protein (GFAP) levels is an early event in the progression of blood biomarker changes in preclinical AD. In AD-converters who are initially cognitively unimpaired (N=158, 377 serial plasma samples), higher plasma GFAP levels are observed as early as 10-years prior to the onset of cognitive impairment due to incident AD compared to individuals who remain cognitively unimpaired (CU, N=160, 379 serial plasma samples). Plasma GFAP levels in AD-converters remain elevated 5-years prior to and coincident with the onset of cognitive impairment due to AD. In participants with neuropathologically confirmed AD, plasma GFAP levels are elevated relative to cognitively normal individuals and intermediate in those who remain cognitively unimpaired despite significant AD pathology (asymptomatic AD). Higher plasma GFAP levels at death are associated with greater severity of both neuritic plaques and neurofibrillary tangles. In the 5XFAD transgenic model of AD, we observed greater GFAP levels in the cortex and hippocampus of transgenic mice relative to wild-type prior to the development of cognitive impairment. Reactive astrocytosis, an established biological response to neuronal injury, may be an early initiator of AD pathogenesis and a promising therapeutic target.
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Affiliation(s)
- V R Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Y An
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - P R Kac
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
| | - M Bilgel
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - A Moghekar
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | - T Loeffler
- Scantox Neuro GmbH, Parkring 12, 8074, Grambach, Austria
| | - D Amschl
- Scantox Neuro GmbH, Parkring 12, 8074, Grambach, Austria
| | - J Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - K Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - H Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - N J Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- King's College London, Institute of Psychiatry, Psychology and Neuroscience Maurice Wohl Institute Clinical Neuroscience Institute London UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation London UK
- Centre for Age-Related Medicine, Stavanger University Hospital, Stavanger, Norway
| | - S M Resnick
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - M Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
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3
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Roberts JA, Basu-Roy S, Shin J, Varma VR, Williamson A, Blackshear C, Griswold ME, Candia J, Elango P, Karikkineth AC, Tanaka T, Ferrucci L, Thambisetty M. Serum Proteomic Signatures of Common Health Outcomes among Older Adults. Gerontology 2024; 70:269-278. [PMID: 38219723 DOI: 10.1159/000534753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 10/09/2023] [Indexed: 01/16/2024] Open
Abstract
INTRODUCTION In aging populations, the coexistence of multiple health comorbidities represents a significant challenge for clinicians and researchers. Leveraging advances in omics techniques to characterize these health conditions may provide insight into disease pathogenesis as well as reveal biomarkers for monitoring, prognostication, and diagnosis. Researchers have previously established the utility of big data approaches with respect to comprehensive health outcome measurements in younger populations, identifying protein markers that may provide significant health information with a single blood sample. METHODS Here, we employed a similar approach in two cohorts of older adults, the Baltimore Longitudinal Study of Aging (mean age = 76.12 years) and InCHIANTI Study (mean age = 66.05 years), examining the relationship between levels of serum proteins and 5 key health outcomes: kidney function, fasting glucose, physical activity, lean body mass, and percent body fat. RESULTS Correlations between proteins and health outcomes were primarily shared across both older adult cohorts. We further identified that most proteins associated with health outcomes in the older adult cohorts were not associated with the same outcomes in a prior study of a younger population. A subset of proteins, adiponectin, MIC-1, and NCAM-120, were associated with at least three health outcomes in both older adult cohorts but not in the previously published younger cohort, suggesting that they may represent plausible markers of general health in older adult populations. CONCLUSION Taken together, these findings suggest that comprehensive protein health markers have utility in aging populations and are distinct from those identified in younger adults, indicating unique mechanisms of disease with aging.
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Affiliation(s)
- Jackson A Roberts
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA,
- Columbia University Vagelos College of Physicians and Surgeons, New York, New York, USA,
| | - Sayantani Basu-Roy
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Jong Shin
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Vijay R Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Andrew Williamson
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Chad Blackshear
- University of Mississippi Medical Center, Jackson, Mississippi, USA
| | | | - Julián Candia
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Palchamy Elango
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Ajoy C Karikkineth
- Clinical Research Core, National Institute on Aging, National Institutes of Health Intramural Research Program, Baltimore, Maryland, USA
| | - Toshiko Tanaka
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
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Ghosal R, Varma VR, Volfson D, Hillel I, Urbanek J, Hausdorff JM, Watts A, Zipunnikov V. Distributional data analysis via quantile functions and its application to modeling digital biomarkers of gait in Alzheimer's Disease. Biostatistics 2023; 24:539-561. [PMID: 36519565 PMCID: PMC10544806 DOI: 10.1093/biostatistics/kxab041] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 09/10/2021] [Accepted: 10/19/2021] [Indexed: 07/20/2023] Open
Abstract
With the advent of continuous health monitoring with wearable devices, users now generate their unique streams of continuous data such as minute-level step counts or heartbeats. Summarizing these streams via scalar summaries often ignores the distributional nature of wearable data and almost unavoidably leads to the loss of critical information. We propose to capture the distributional nature of wearable data via user-specific quantile functions (QF) and use these QFs as predictors in scalar-on-quantile-function-regression (SOQFR). As an alternative approach, we also propose to represent QFs via user-specific L-moments, robust rank-based analogs of traditional moments, and use L-moments as predictors in SOQFR (SOQFR-L). These two approaches provide two mutually consistent interpretations: in terms of quantile levels by SOQFR and in terms of L-moments by SOQFR-L. We also demonstrate how to deal with multi-modal distributional data via Joint and Individual Variation Explained using L-moments. The proposed methods are illustrated in a study of association of digital gait biomarkers with cognitive function in Alzheimers disease. Our analysis shows that the proposed methods demonstrate higher predictive performance and attain much stronger associations with clinical cognitive scales compared to simple distributional summaries.
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Affiliation(s)
- Rahul Ghosal
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Vijay R Varma
- National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Dmitri Volfson
- Neuroscience Analytics, Computational Biology, Takeda, Cambridge, MA, USA
| | - Inbar Hillel
- Center for the Study of Movement, Cognition and Mobility, Neurological Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Jacek Urbanek
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jeffrey M Hausdorff
- Center for the Study of Movement, Cognition and Mobility, Neurological Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel, Department of Physical Therapy, Sackler Faculty of Medicine, and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel, and Rush Alzheimer’s Disease Center and Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA
| | - Amber Watts
- Department of Psychology, University of Kansas, Lawrence, KS, USA
| | - Vadim Zipunnikov
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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5
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Roberts JA, Varma VR, Candia J, Tanaka T, Ferrucci L, Bennett DA, Thambisetty M. Unbiased proteomics and multivariable regularized regression techniques identify SMOC1, NOG, APCS, and NTN1 in an Alzheimer's disease brain proteomic signature. NPJ Aging 2023; 9:18. [PMID: 37414805 PMCID: PMC10326005 DOI: 10.1038/s41514-023-00112-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 05/18/2023] [Indexed: 07/08/2023]
Abstract
Advancements in omics methodologies have generated a wealth of high-dimensional Alzheimer's disease (AD) datasets, creating significant opportunities and challenges for data interpretation. In this study, we utilized multivariable regularized regression techniques to identify a reduced set of proteins that could discriminate between AD and cognitively normal (CN) brain samples. Utilizing eNetXplorer, an R package that tests the accuracy and significance of a family of elastic net generalized linear models, we identified 4 proteins (SMOC1, NOG, APCS, NTN1) that accurately discriminated between AD (n = 31) and CN (n = 22) middle frontal gyrus (MFG) tissue samples from Religious Orders Study participants with 83 percent accuracy. We then validated this signature in MFG samples from Baltimore Longitudinal Study of Aging participants using leave-one-out logistic regression cross-validation, finding that the signature again accurately discriminated AD (n = 31) and CN (n = 19) participants with a receiver operating characteristic curve area under the curve of 0.863. These proteins were strongly correlated with the burden of neurofibrillary tangle and amyloid pathology in both study cohorts. We additionally tested whether these proteins differed between AD and CN inferior temporal gyrus (ITG) samples and blood serum samples at the time of AD diagnosis in ROS and BLSA, finding that the proteins differed between AD and CN ITG samples but not in blood serum samples. The identified proteins may provide mechanistic insights into the pathophysiology of AD, and the methods utilized in this study may serve as the basis for further work with additional high-dimensional datasets in AD.
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Affiliation(s)
- Jackson A Roberts
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA.
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, 10032, USA.
| | - Vijay R Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Julián Candia
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Toshiko Tanaka
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, 60612, USA
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA.
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6
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Desai RJ, Mahesri M, Lee SB, Varma VR, Loeffler T, Schilcher I, Gerhard T, Segal JB, Ritchey ME, Horton DB, Kim SC, Schneeweiss S, Thambisetty M. No association between initiation of phosphodiesterase-5 inhibitors and risk of incident Alzheimer's disease and related dementia: results from the Drug Repurposing for Effective Alzheimer's Medicines study. Brain Commun 2022; 4:fcac247. [PMID: 36330433 PMCID: PMC9598543 DOI: 10.1093/braincomms/fcac247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/11/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022] Open
Abstract
We evaluated the hypothesis that phosphodiesterase-5 inhibitors, including sildenafil and tadalafil, may be associated with reduced incidence of Alzheimer's disease and related dementia using a patient-level cohort study of Medicare claims and cell culture-based phenotypic assays. We compared incidence of Alzheimer's disease and related dementia after phosphodiesterase-5 inhibitor initiation versus endothelin receptor antagonist initiation among patients with pulmonary hypertension after controlling for 76 confounding variables through propensity score matching. Across four separate analytic approaches designed to address specific types of biases including informative censoring, reverse causality, and outcome misclassification, we observed no evidence for a reduced risk of Alzheimer's disease and related dementia with phosphodiesterase-5 inhibitors;hazard ratio (95% confidence interval): 0.99 (0.69-1.43), 1.00 (0.71-1.42), 0.67 (0.43-1.06), and 1.15 (0.57-2.34). We also did not observe evidence that sildenafil ameliorated molecular abnormalities relevant to Alzheimer's disease in most cell culture-based phenotypic assays. These results do not provide support to the hypothesis that phosphodiesterase-5 inhibitors are promising repurposing candidates for Alzheimer's disease and related dementia.
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Affiliation(s)
- Rishi J Desai
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital & Harvard Medical School, Boston, MA 02115, USA
| | - Mufaddal Mahesri
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital & Harvard Medical School, Boston, MA 02115, USA
| | - Su Been Lee
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital & Harvard Medical School, Boston, MA 02115, USA
| | - Vijay R Varma
- Clinical & Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD 21224, USA
| | - Tina Loeffler
- QPS Austria GmbH, Parkring 12, 8074 Grambach, Austria
| | | | - Tobias Gerhard
- Rutgers Center for Pharmacoepidemiology and Treatment Science, New Brunswick, NJ 08901, USA
- Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854, USA
| | - Jodi B Segal
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Mary E Ritchey
- Rutgers Center for Pharmacoepidemiology and Treatment Science, New Brunswick, NJ 08901, USA
| | - Daniel B Horton
- Rutgers Center for Pharmacoepidemiology and Treatment Science, New Brunswick, NJ 08901, USA
- Rutgers Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08901, USA
| | - Seoyoung C Kim
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital & Harvard Medical School, Boston, MA 02115, USA
- Division of Rheumatology, Inflammation, and Immunity, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Sebastian Schneeweiss
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital & Harvard Medical School, Boston, MA 02115, USA
| | - Madhav Thambisetty
- Clinical & Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD 21224, USA
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7
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Ghosal R, Varma VR, Volfson D, Urbanek J, Hausdorff JM, Watts A, Zipunnikov V. Scalar on time-by-distribution regression and its application for modelling associations between daily-living physical activity and cognitive functions in Alzheimer's Disease. Sci Rep 2022; 12:11558. [PMID: 35798763 PMCID: PMC9263176 DOI: 10.1038/s41598-022-15528-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 06/24/2022] [Indexed: 11/26/2022] Open
Abstract
Wearable data is a rich source of information that can provide a deeper understanding of links between human behaviors and human health. Existing modelling approaches use wearable data summarized at subject level via scalar summaries in regression, temporal (time-of-day) curves in functional data analysis (FDA), and distributions in distributional data analysis (DDA). We propose to capture temporally local distributional information in wearable data using subject-specific time-by-distribution (TD) data objects. Specifically, we develop scalar on time-by-distribution regression (SOTDR) to model associations between scalar response of interest such as health outcomes or disease status and TD predictors. Additionally, we show that TD data objects can be parsimoniously represented via a collection of time-varying L-moments that capture distributional changes over the time-of-day. The proposed method is applied to the accelerometry study of mild Alzheimer’s disease (AD). We found that mild AD is significantly associated with reduced upper quantile levels of physical activity, particularly during morning hours. In-sample cross validation demonstrated that TD predictors attain much stronger associations with clinical cognitive scales of attention, verbal memory, and executive function when compared to predictors summarized via scalar total activity counts, temporal functional curves, and quantile functions. Taken together, the present results suggest that SOTDR analysis provides novel insights into cognitive function and AD.
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Affiliation(s)
- Rahul Ghosal
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Vijay R Varma
- National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Dmitri Volfson
- Neuroscience Analytics, Computational Biology, Takeda, Cambridge, MA, USA
| | - Jacek Urbanek
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jeffrey M Hausdorff
- Center for the Study of Movement, Cognition and Mobility, Neurological Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Department of Physical Therapy, Sackler Faculty of Medicine, and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.,Rush Alzheimer's Disease Center and Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA
| | - Amber Watts
- Department of Psychology, University of Kansas, Lawrence, KS, USA
| | - Vadim Zipunnikov
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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8
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Desai RJ, Varma VR, Gerhard T, Segal J, Mahesri M, Chin K, Horton DB, Kim SC, Schneeweiss S, Thambisetty M. Comparative Risk of Alzheimer Disease and Related Dementia Among Medicare Beneficiaries With Rheumatoid Arthritis Treated With Targeted Disease-Modifying Antirheumatic Agents. JAMA Netw Open 2022; 5:e226567. [PMID: 35394510 PMCID: PMC8994126 DOI: 10.1001/jamanetworkopen.2022.6567] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
IMPORTANCE Cytokine signaling, including tumor necrosis factor (TNF) and interleukin (IL)-6, through the Janus-kinase (JAK)-signal transducer and activator of transcription pathway, was hypothesized to attenuate the risk of Alzheimer disease and related dementia (ADRD) in the Drug Repurposing for Effective Alzheimer Medicines (DREAM) initiative based on multiomics phenotyping. OBJECTIVE To evaluate the association between treatment with tofacitinib, tocilizumab, or TNF inhibitors compared with abatacept and risk of incident ADRD. DESIGN, SETTING, AND PARTICIPANTS This cohort study was conducted among US Medicare fee-for-service patients with rheumatoid arthritis aged 65 years and older from 2007 to 2017. Patients were categorized into 3 cohorts based on initiation of tofacitinib (a JAK inhibitor), tocilizumab (an IL-6 inhibitor), or TNF inhibitors compared with a common comparator abatacept (a T-cell activation inhibitor). Analyses were conducted from August 2020 to August 2021. MAIN OUTCOMES AND MEASURES The main outcome was onset of ADRD based on diagnosis codes evaluated in 4 alternative analysis schemes: (1) an as-treated follow-up approach, (2) an as-started follow-up approach incorporating a 6-month induction period, (3) incorporating a 6-month symptom to diagnosis period to account for misclassification of ADRD onset, and (4) identifying ADRD through symptomatic prescriptions and diagnosis codes. Hazard ratios (HRs) with 95% CIs were calculated from Cox proportional hazard regression after adjustment for 79 preexposure characteristics through propensity score matching. RESULTS After 1:1 propensity score matching to patients using abatacept, a total of 22 569 propensity score-matched patient pairs, including 4224 tofacitinib pairs (mean [SD] age 72.19 [5.65] years; 6945 [82.2%] women), 6369 tocilizumab pairs (mean [SD] age 72.01 [5.46] years; 10 105 [79.4%] women), and 11 976 TNF inhibitor pairs (mean [SD] age 72.67 [5.91] years; 19 710 [82.3%] women), were assessed. Incidence rates of ADRD varied from 2 to 18 per 1000 person-years across analyses schemes. There were no statistically significant associations of ADRD with tofacitinib (analysis 1: HR, 0.90 [95% CI, 0.55-1.51]; analysis 2: HR, 0.78 [95% CI, 0.53-1.13]; analysis 3: HR, 1.29 [95% CI, 0.72-2.33]; analysis 4: HR, 0.50 [95% CI, 0.21-1.20]), tocilizumab (analysis 1: HR, 0.82 [95% CI, 0.55-1.21]; analysis 2: HR, 1.05 [95% CI, 0.81-1.35]; analysis 3: HR, 1.21 [95% CI, 0.75-1.96]; analysis 4: HR, 0.78 [95% CI, 0.44-1.39]), or TNF inhibitors (analysis 1: HR, 0.93 [95% CI, 0.72-1.20]; analysis 2: HR, 1.02 [95% CI, 0.86-1.20]; analysis 3: HR, 1.13 [95% CI, 0.86-1.48]; analysis 4: 0.90 [95% CI, 0.60-1.37]) compared with abatacept. Results from prespecified subgroup analysis by age, sex, and baseline cardiovascular disease were consistent except in patients with cardiovascular disease, for whom there was a potentially lower risk of ADRD with TNF inhibitors vs abatacept, but only in analyses 2 and 4 (analysis 1: HR, 0.76 [95% CI, 0.50-1.16]; analysis 2: HR, 0.74 [95% CI, 0.56-0.99]; analysis 3: HR, 1.03 [95% CI, 0.65-1.61]; analysis 4: HR, 0.45 [95% CI, 0.21-0.98]). CONCLUSIONS AND RELEVANCE This cohort study did not find any association of risk of ADRD in patients treated with tofacitinib, tocilizumab, or TNF inhibitors compared with abatacept.
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Affiliation(s)
- Rishi J. Desai
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Vijay R. Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, Maryland
| | - Tobias Gerhard
- Center for Pharmacoepidemiology and Treatment Science, Ernest Mario School of Pharmacy, Rutgers University, New Brunswick, New Jersey
| | - Jodi Segal
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mufaddal Mahesri
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Kristyn Chin
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Daniel B. Horton
- Center for Pharmacoepidemiology and Treatment Science, Ernest Mario School of Pharmacy, Rutgers University, New Brunswick, New Jersey
| | - Seoyoung C. Kim
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
- Division of Rheumatology, Inflammation, and Immunity, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Sebastian Schneeweiss
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, Maryland
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9
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Ashton NJ, Karikari TK, Rodriguez JL, Benedet AL, Snellman A, Pascoal TA, Gauthier S, Rosa‐Neto P, Jack CR, Petersen RC, Mielke MM, Chatterjee P, Martins RN, Thambisetty M, Varma VR, Resnick SM, Fox NC, O'Connor A, Vrillon A, Paquet C, Villeneuve S, Poirier J, Group PR, Galasko DR, Milà‐Alomà M, Minguillón C, Fauria K, Suarez‐Calvet M, Vanmechelen E, Zetterberg H, Blennow K. Plasma p‐tau231 in the Alzheimer’s disease continuum: A multi‐cohort evaluation of diagnostic performance, detection of Aβ pathology and preclinical application. Alzheimers Dement 2021. [DOI: 10.1002/alz.056186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Nicholas J. Ashton
- Institute of Neuroscience and Physiology Sahlgrenska Academy at the University of Gothenburg Mölndal Sweden
- Institute of Psychiatry Psychology & Neuroscience King's College London London United Kingdom
| | - Thomas K. Karikari
- Institute of Neuroscience and Physiology University of Gothenburg Mölndal Sweden
| | | | | | - Anniina Snellman
- The Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | | | | | | | | | | | | | | | - Ralph N. Martins
- Department of Biomedical Sciences Macquarie University Macquarie Park NSW Australia
| | | | | | - Susan M. Resnick
- Laboratory of Behavioral Neuroscience National Institute on Aging Baltimore MD USA
| | - Nick C. Fox
- Dementia Research Centre London United Kingdom
| | - Antoinette O'Connor
- Dementia Research Centre UCL Queen Square Institute of Neurology London United Kingdom
| | - Agathe Vrillon
- Cognitive Neurology Center Hôpital Lariboisière‐Fernand Widal APHP France Paris France
| | - Claire Paquet
- Cognitive Neurology Center Hôpital Lariboisière‐Fernand Widal APHP Paris France
| | | | - Judes Poirier
- Douglas Mental Health University Institute Montreal QC Canada
| | - Prevent‐AD Research Group
- Centre for Studies on Prevention of Alzheimer's Disease (StoP‐AD Centre) Douglas Mental Health Institute Montreal QC Canada
| | | | - Marta Milà‐Alomà
- Barcelonaβeta Brain Research Center (BBRC) Pasqual Maragall Foundation Barcelona Spain
| | - Carolina Minguillón
- Barcelonaβeta Brain Research Center (BBRC) Pasqual Maragall Foundation Barcelona Spain
| | - Karine Fauria
- Barcelonaβeta Brain Research Center (BBRC) Pasqual Maragall Foundation Barcelona Spain
| | - Marc Suarez‐Calvet
- Barcelonaβeta Brain Research Center (BBRC) Pasqual Maragall Foundation Barcelona Spain
| | | | - Henrik Zetterberg
- Institute of Neuroscience and Physiology The Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Kaj Blennow
- Institute of Neuroscience and Physiology University of Gothenburg Mölndal Sweden
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Roberts JA, Varma VR, An Y, Varma S, Candia J, Fantoni G, Tiwari V, Anerillas C, Williamson A, Saito A, Loeffler T, Schilcher I, Moaddel R, Khadeer M, Lovett J, Tanaka T, Pletnikova O, Troncoso JC, Bennett DA, Albert MS, Yu K, Niu M, Haroutunian V, Zhang B, Peng J, Croteau DL, Resnick SM, Gorospe M, Bohr VA, Ferrucci L, Thambisetty M. A brain proteomic signature of incipient Alzheimer's disease in young APOE ε4 carriers identifies novel drug targets. Sci Adv 2021; 7:eabi8178. [PMID: 34757788 PMCID: PMC8580310 DOI: 10.1126/sciadv.abi8178] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Aptamer-based proteomics revealed differentially abundant proteins in Alzheimer’s disease (AD) brains in the Baltimore Longitudinal Study of Aging and Religious Orders Study (mean age, 89 ± 9 years). A subset of these proteins was also differentially abundant in the brains of young APOE ε4 carriers relative to noncarriers (mean age, 39 ± 6 years). Several of these proteins represent targets of approved and experimental drugs for other indications and were validated using orthogonal methods in independent human brain tissue samples as well as in transgenic AD models. Using cell culture–based phenotypic assays, we showed that drugs targeting the cytokine transducer STAT3 and the Src family tyrosine kinases, YES1 and FYN, rescued molecular phenotypes relevant to AD pathogenesis. Our findings may accelerate the development of effective interventions targeting the earliest molecular triggers of AD.
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Affiliation(s)
- Jackson A Roberts
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032
| | - Vijay R Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Yang An
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | | | - Julián Candia
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Giovanna Fantoni
- Clinical Research Core, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Vinod Tiwari
- Section on DNA Repair, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Carlos Anerillas
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Andrew Williamson
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Atsushi Saito
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Tina Loeffler
- QPS Austria GmbH, Parkring 12, 8074 Grambach, Austria
| | | | - Ruin Moaddel
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Mohammed Khadeer
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Jacqueline Lovett
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Toshiko Tanaka
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Olga Pletnikova
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | - Juan C Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Marilyn S Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Kaiwen Yu
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Mingming Niu
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Vahram Haroutunian
- Departments of Psychiatry and Neuroscience, The Alzheimer's Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Mental Illness Research, Education and Clinical Center (MIRECC), James J. Peters VA Medical Center, Bronx, NY 10468, USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences and Department of Pharmacological Sciences, Mount Sinai Center for Transformative Disease Modeling, Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Junmin Peng
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Deborah L Croteau
- Section on DNA Repair, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Susan M Resnick
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Vilhelm A Bohr
- Section on DNA Repair, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
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11
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Munk R, Anerillas C, Rossi M, Tsitsipatis D, Martindale JL, Herman AB, Yang JH, Roberts JA, Varma VR, Pandey PR, Thambisetty M, Gorospe M, Abdelmohsen K. Acid ceramidase promotes senescent cell survival. Aging (Albany NY) 2021; 13:15750-15769. [PMID: 34102611 PMCID: PMC8266329 DOI: 10.18632/aging.203170] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 05/18/2021] [Indexed: 01/18/2023]
Abstract
Cellular senescence is linked to chronic age-related diseases including atherosclerosis, diabetes, and neurodegeneration. Compared to proliferating cells, senescent cells express distinct subsets of proteins. In this study, we used cultured human diploid fibroblasts rendered senescent through replicative exhaustion or ionizing radiation to identify proteins differentially expressed during senescence. We identified acid ceramidase (ASAH1), a lysosomal enzyme that cleaves ceramide into sphingosine and fatty acid, as being highly elevated in senescent cells. This increase in ASAH1 levels in senescent cells was associated with a rise in the levels of ASAH1 mRNA and a robust increase in ASAH1 protein stability. Furthermore, silencing ASAH1 in pre-senescent fibroblasts decreased the levels of senescence proteins p16, p21, and p53, and reduced the activity of the senescence-associated β-galactosidase. Interestingly, depletion of ASAH1 in pre-senescent cells sensitized these cells to the senolytics Dasatinib and Quercetin (D+Q). Together, our study indicates that ASAH1 promotes senescence, protects senescent cells, and confers resistance against senolytic drugs. Given that inhibiting ASAH1 sensitizes cells towards senolysis, this enzyme represents an attractive therapeutic target in interventions aimed at eliminating senescent cells.
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Affiliation(s)
- Rachel Munk
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Carlos Anerillas
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Martina Rossi
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Dimitrios Tsitsipatis
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Jennifer L Martindale
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Allison B Herman
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Jen-Hao Yang
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Jackson A Roberts
- Laboratory of Behavioral Neuroscience, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Vijay R Varma
- Laboratory of Behavioral Neuroscience, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Poonam R Pandey
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Madhav Thambisetty
- Laboratory of Behavioral Neuroscience, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Kotb Abdelmohsen
- Laboratory of Genetics and Genomics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
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12
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Yasar S, Moored KD, Adam A, Zabel F, Chuang YF, Varma VR, Carlson MC. Angiotensin II Blood Levels Are Associated with Smaller Hippocampal and Cortical Volumes in Cognitively Normal Older Adults. J Alzheimers Dis 2021; 75:521-529. [PMID: 32280103 DOI: 10.3233/jad-200118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND There is emerging evidence about possible involvement of the renin-angiotensin system (RAS) in the pathogenesis of Alzheimer's disease (AD) and decline of cognitive function. However, little is known about associations with brain biomarkers. OBJECTIVE Our study aimed to examine associations between blood ACE-1 and ANG II levels and brain MRI based volumes in non-demented participants, and whether these associations were mediated by blood pressure. METHODS This cross-sectional study was conducted in 34 older participants from the Baltimore Experience Corps Trial (BECT) Brain Health Sub-study (BHS). Blood ANGII and ACE-1 levels were measured by ELISA and brain MRI volumes were generated using FreeSurfer 6.0. Multiple linear regression analysis, adjusting for intracranial volume and confounders, was used to determine associations between log transformed ANGII and ACE-1 levels and MRI volumes (mm3). RESULTS Participants were predominantly female (76%), African-American (94%), with mean age of 66.9 and education of 14.4 years. In the fully adjusted model we observed significant inverse associations between log ANGII levels and total grey matter (β=Angiotensin II associated with smaller hippocampus14,935.50, ±7,444.83, p = 0.05), total hippocampus (β=-129.97, ±105.27, p = 0.03), rostral middle frontal (β= -1580.40, ±584.74, p = 0.02), and supramarginal parietal (β= -978.90, ±365.54, p = 0.02) volumes. There were no associations between ANGII levels and total white matter or entorhinal cortex volumes, or ACE-1 levels and any brain volumes. CONCLUSION We observed that increased blood ANGII levels were associated with lower total grey matter, hippocampal, rostral middle frontal, and supramarginal parietal volumes, which are associated with cognitive domains that decline in preclinical AD.
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Affiliation(s)
- Sevil Yasar
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Kyle D Moored
- Department of Mental Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Atif Adam
- Department of Mental Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Fiona Zabel
- Baltimore Polytechnic Institute, Baltimore, MD, USA
| | - Yi-Fang Chuang
- Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
| | - Vijay R Varma
- National Institute on Aging, Intramural Research program, Laboratory of Behavioral Neuroscience, Baltimore, MD, USA
| | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
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13
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Varma VR, Wang Y, An Y, Varma S, Bilgel M, Doshi J, Legido-Quigley C, Delgado JC, Oommen AM, Roberts JA, Wong DF, Davatzikos C, Resnick SM, Troncoso JC, Pletnikova O, O’Brien R, Hak E, Baak BN, Pfeiffer R, Baloni P, Mohmoudiandehkordi S, Nho K, Kaddurah-Daouk R, Bennett DA, Gadalla SM, Thambisetty M. Bile acid synthesis, modulation, and dementia: A metabolomic, transcriptomic, and pharmacoepidemiologic study. PLoS Med 2021; 18:e1003615. [PMID: 34043628 PMCID: PMC8158920 DOI: 10.1371/journal.pmed.1003615] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/06/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND While Alzheimer disease (AD) and vascular dementia (VaD) may be accelerated by hypercholesterolemia, the mechanisms underlying this association are unclear. We tested whether dysregulation of cholesterol catabolism, through its conversion to primary bile acids (BAs), was associated with dementia pathogenesis. METHODS AND FINDINGS We used a 3-step study design to examine the role of the primary BAs, cholic acid (CA), and chenodeoxycholic acid (CDCA) as well as their principal biosynthetic precursor, 7α-hydroxycholesterol (7α-OHC), in dementia. In Step 1, we tested whether serum markers of cholesterol catabolism were associated with brain amyloid accumulation, white matter lesions (WMLs), and brain atrophy. In Step 2, we tested whether exposure to bile acid sequestrants (BAS) was associated with risk of dementia. In Step 3, we examined plausible mechanisms underlying these findings by testing whether brain levels of primary BAs and gene expression of their principal receptors are altered in AD. Step 1: We assayed serum concentrations CA, CDCA, and 7α-OHC and used linear regression and mixed effects models to test their associations with brain amyloid accumulation (N = 141), WMLs, and brain atrophy (N = 134) in the Baltimore Longitudinal Study of Aging (BLSA). The BLSA is an ongoing, community-based cohort study that began in 1958. Participants in the BLSA neuroimaging sample were approximately 46% male with a mean age of 76 years; longitudinal analyses included an average of 2.5 follow-up magnetic resonance imaging (MRI) visits. We used the Alzheimer's Disease Neuroimaging Initiative (ADNI) (N = 1,666) to validate longitudinal neuroimaging results in BLSA. ADNI is an ongoing, community-based cohort study that began in 2003. Participants were approximately 55% male with a mean age of 74 years; longitudinal analyses included an average of 5.2 follow-up MRI visits. Lower serum concentrations of 7α-OHC, CA, and CDCA were associated with higher brain amyloid deposition (p = 0.041), faster WML accumulation (p = 0.050), and faster brain atrophy mainly (false discovery rate [FDR] p = <0.001-0.013) in males in BLSA. In ADNI, we found a modest sex-specific effect indicating that lower serum concentrations of CA and CDCA were associated with faster brain atrophy (FDR p = 0.049) in males.Step 2: In the Clinical Practice Research Datalink (CPRD) dataset, covering >4 million registrants from general practice clinics in the United Kingdom, we tested whether patients using BAS (BAS users; 3,208 with ≥2 prescriptions), which reduce circulating BAs and increase cholesterol catabolism, had altered dementia risk compared to those on non-statin lipid-modifying therapies (LMT users; 23,483 with ≥2 prescriptions). Patients in the study (BAS/LMT) were approximately 34%/38% male and with a mean age of 65/68 years; follow-up time was 4.7/5.7 years. We found that BAS use was not significantly associated with risk of all-cause dementia (hazard ratio (HR) = 1.03, 95% confidence interval (CI) = 0.72-1.46, p = 0.88) or its subtypes. We found a significant difference between the risk of VaD in males compared to females (p = 0.040) and a significant dose-response relationship between BAS use and risk of VaD (p-trend = 0.045) in males.Step 3: We assayed brain tissue concentrations of CA and CDCA comparing AD and control (CON) samples in the BLSA autopsy cohort (N = 29). Participants in the BLSA autopsy cohort (AD/CON) were approximately 50%/77% male with a mean age of 87/82 years. We analyzed single-cell RNA sequencing (scRNA-Seq) data to compare brain BA receptor gene expression between AD and CON samples from the Religious Orders Study and Memory and Aging Project (ROSMAP) cohort (N = 46). ROSMAP is an ongoing, community-based cohort study that began in 1994. Participants (AD/CON) were approximately 56%/36% male with a mean age of 85/85 years. In BLSA, we found that CA and CDCA were detectable in postmortem brain tissue samples and were marginally higher in AD samples compared to CON. In ROSMAP, we found sex-specific differences in altered neuronal gene expression of BA receptors in AD. Study limitations include the small sample sizes in the BLSA cohort and likely inaccuracies in the clinical diagnosis of dementia subtypes in primary care settings. CONCLUSIONS We combined targeted metabolomics in serum and amyloid positron emission tomography (PET) and MRI of the brain with pharmacoepidemiologic analysis to implicate dysregulation of cholesterol catabolism in dementia pathogenesis. We observed that lower serum BA concentration mainly in males is associated with neuroimaging markers of dementia, and pharmacological lowering of BA levels may be associated with higher risk of VaD in males. We hypothesize that dysregulation of BA signaling pathways in the brain may represent a plausible biologic mechanism underlying these results. Together, our observations suggest a novel mechanism relating abnormalities in cholesterol catabolism to risk of dementia.
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Affiliation(s)
- Vijay R. Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Youjin Wang
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Yang An
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Sudhir Varma
- HiThru Analytics, Laurel, Maryland, United States of America
| | - Murat Bilgel
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Jimit Doshi
- Section for Biomedical Image Analysis, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | | | - João C. Delgado
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Anup M. Oommen
- Glycoscience Group, NCBES National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
| | - Jackson A. Roberts
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Dean F. Wong
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Christos Davatzikos
- Section for Biomedical Image Analysis, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Susan M. Resnick
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Juan C. Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Olga Pletnikova
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Richard O’Brien
- Department of Neurology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Eelko Hak
- Groningen Research Institute of Pharmacy, University of Groningen, Groningen, the Netherlands
| | - Brenda N. Baak
- Groningen Research Institute of Pharmacy, University of Groningen, Groningen, the Netherlands
| | - Ruth Pfeiffer
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Priyanka Baloni
- Institute for Systems Biology, Seattle, Washington, United States of America
| | - Siamak Mohmoudiandehkordi
- Department of Psychiatry and Behavioral Sciences, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Kwangsik Nho
- Department of Radiology and Imaging Sciences and the Indiana Alzheimer Disease Center, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Rima Kaddurah-Daouk
- Department of Psychiatry and Behavioral Sciences, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Shahinaz M. Gadalla
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
- * E-mail:
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14
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Moored KD, Chan T, Varma VR, Chuang YF, Parisi JM, Carlson MC. Engagement in Enriching Early-Life Activities Is Associated With Larger Hippocampal and Amygdala Volumes in Community-Dwelling Older Adults. J Gerontol B Psychol Sci Soc Sci 2021; 75:1637-1647. [PMID: 30561728 DOI: 10.1093/geronb/gby150] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVES Numerous studies show benefits of mid- and late-life activity on neurocognitive health. Yet, few studies have examined how engagement in enriching activities during childhood, when the brain is most plastic, may confer long-term neurocognitive benefits that may be especially important to individuals raised in low-income settings. We examined associations between enriching early-life activities (EELAs) and hippocampal and amygdala volumes in a sample of predominantly African-American, community-dwelling older adults. We further assessed whether these associations were independent of current activity engagement. METHODS Ninety participants from the baseline Brain Health Substudy of the Baltimore Experience Corps Trial (mean age: 67.4) completed retrospective activity inventories and an magnetic resonance imaging scan. Volumes were segmented using FreeSurfer. RESULTS Each additional EELA was associated with a 2.3% (66.6 mm3) greater amygdala volume after adjusting for covariates. For men, each additional EELA was associated with a 4.1% (278.9 mm3) greater hippocampal volume. Associations were specific to these regions when compared with the thalamus, used as a control region. DISCUSSION Enriching lifestyle activities during an important window of childhood brain development may be a modifiable factor that impacts lifelong brain reserve, and results highlight the importance of providing access to such activities in historically underserved populations.
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Affiliation(s)
- Kyle D Moored
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Thomas Chan
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Vijay R Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland
| | - Yi-Fang Chuang
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland.,Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
| | - Jeanine M Parisi
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
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15
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Varma VR, Ghosal R, Hillel I, Volfson D, Weiss J, Urbanek J, Hausdorff JM, Zipunnikov V, Watts A. Continuous gait monitoring discriminates community-dwelling mild Alzheimer's disease from cognitively normal controls. Alzheimers Dement (N Y) 2021; 7:e12131. [PMID: 33598530 PMCID: PMC7864220 DOI: 10.1002/trc2.12131] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 11/25/2020] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Few studies have explored whether gait measured continuously within a community setting can identify individuals with Alzheimer's disease (AD). This study tests the feasibility of this method to identify individuals at the earliest stage of AD. METHODS Mild AD (n = 38) and cognitively normal control (CNC; n = 48) participants from the University of Kansas Alzheimer's Disease Center Registry wore a GT3x+ accelerometer continuously for 7 days to assess gait. Penalized logistic regression with repeated five-fold cross-validation followed by adjusted logistic regression was used to identify gait metrics with the highest predictive performance in discriminating mild AD from CNC. RESULTS Variability in step velocity and cadence had the highest predictive utility in identifying individuals with mild AD. Metrics were also associated with cognitive domains impacted in early AD. DISCUSSION Continuous gait monitoring may be a scalable method to identify individuals at-risk for developing dementia within large, population-based studies.
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Affiliation(s)
- Vijay R. Varma
- Clinical and Translational Neuroscience SectionLaboratory of Behavioral NeuroscienceNational Institute on Aging (NIA)National Institutes of Health (NIH)BaltimoreMarylandUSA
| | - Rahul Ghosal
- Department of BiostatisticsJohns Hopkins Bloomberg School of Public HealthBaltimoreMarylandUSA
| | - Inbar Hillel
- Center for the Study of Movement, Cognition and MobilityTel Aviv Sourasky Medical Center, Neurological InstituteTel AvivIsrael
| | - Dmitri Volfson
- Neuroscience AnalyticsComputational Biology, TakedaCambridgeMassachusettsUSA
| | - Jordan Weiss
- Department of DemographyUniversity of California, BerkeleyBerkeleyCaliforniaUSA
| | - Jacek Urbanek
- Department of MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Jeffrey M. Hausdorff
- Center for the Study of Movement, Cognition and MobilityTel Aviv Sourasky Medical Center, Neurological InstituteTel AvivIsrael
- Sagol School of NeuroscienceTel Aviv UniversityTel AvivIsrael
- Rush Alzheimer's Disease Center and Department of Orthopaedic SurgeryRush University Medical CenterChicagoUSA
- Department of Physical Therapy, Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
| | - Vadim Zipunnikov
- Department of BiostatisticsJohns Hopkins Bloomberg School of Public HealthBaltimoreMarylandUSA
| | - Amber Watts
- Department of PsychologyUniversity of KansasLawrenceKansasUSA
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16
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Desai RJ, Varma VR, Gerhard T, Segal J, Mahesri M, Chin K, Nonnenmacher E, Gabbeta A, Mammen AM, Varma S, Horton DB, Kim SC, Schneeweiss S, Thambisetty M. Targeting abnormal metabolism in Alzheimer's disease: The Drug Repurposing for Effective Alzheimer's Medicines (DREAM) study. Alzheimers Dement (N Y) 2020; 6:e12095. [PMID: 33304987 PMCID: PMC7690721 DOI: 10.1002/trc2.12095] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 09/11/2020] [Indexed: 12/15/2022]
Abstract
Drug discovery for disease-modifying therapies for Alzheimer's disease and related dementias (ADRD) based on the traditional paradigm of experimental animal models has been disappointing. We describe the rationale and design of the Drug Repurposing for Effective Alzheimer's Medicines (DREAM) study, an innovative multidisciplinary alternative to traditional drug discovery. First, we use a systems biology perspective in the "hypothesis generation" phase to identify metabolic abnormalities that may either precede or interact with the accumulation of ADRD neuropathology, accelerating the expression of clinical symptoms of the disease. Second, in the "hypothesis refinement" phase we propose use of large patient cohorts to test whether drugs approved for other indications that also target metabolic drivers of ADRD pathogenesis might alter the trajectory of the disease. We emphasize key challenges in population-based pharmacoepidemiologic studies aimed at quantifying the association between medication use and ADRD onset and outline robust causal inference principles to safeguard against common pitfalls. Candidate ADRD treatments emerging from this approach will hold promise as plausible disease-modifying therapies for evaluation in randomized controlled trials.
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Affiliation(s)
- Rishi J. Desai
- Division of Pharmacoepidemiology and PharmacoeconomicsDepartment of MedicineBrigham and Women's Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Vijay R. Varma
- Clinical and Translational Neuroscience SectionLaboratory of Behavioral NeuroscienceNational Institute on AgingBaltimoreMarylandUSA
| | - Tobias Gerhard
- Center for Pharmacoepidemiology and Treatment ScienceErnest Mario School of PharmacyRutgers UniversityNew BrunswickNew JerseyUSA
| | - Jodi Segal
- Department of MedicineJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Mufaddal Mahesri
- Division of Pharmacoepidemiology and PharmacoeconomicsDepartment of MedicineBrigham and Women's Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Kristyn Chin
- Division of Pharmacoepidemiology and PharmacoeconomicsDepartment of MedicineBrigham and Women's Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Edward Nonnenmacher
- Center for Pharmacoepidemiology and Treatment ScienceErnest Mario School of PharmacyRutgers UniversityNew BrunswickNew JerseyUSA
| | - Avinash Gabbeta
- Center for Pharmacoepidemiology and Treatment ScienceErnest Mario School of PharmacyRutgers UniversityNew BrunswickNew JerseyUSA
| | - Anup M. Mammen
- Glycoscience GroupNCBES National Centre for Biomedical Engineering ScienceNational University of Ireland GalwayGalwayIreland
| | | | - Daniel B. Horton
- Center for Pharmacoepidemiology and Treatment ScienceErnest Mario School of PharmacyRutgers UniversityNew BrunswickNew JerseyUSA
| | - Seoyoung C. Kim
- Division of Pharmacoepidemiology and PharmacoeconomicsDepartment of MedicineBrigham and Women's Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Sebastian Schneeweiss
- Division of Pharmacoepidemiology and PharmacoeconomicsDepartment of MedicineBrigham and Women's Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience SectionLaboratory of Behavioral NeuroscienceNational Institute on AgingBaltimoreMarylandUSA
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17
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Mahajan UV, Varma VR, Griswold ME, Blackshear CT, An Y, Oommen AM, Varma S, Troncoso JC, Pletnikova O, O'Brien R, Hohman TJ, Legido-Quigley C, Thambisetty M. Correction: Dysregulation of multiple metabolic networks related to brain transmethylation and polyamine pathways in Alzheimer disease: A targeted metabolomic and transcriptomic study. PLoS Med 2020; 17:e1003439. [PMID: 33085665 PMCID: PMC7577459 DOI: 10.1371/journal.pmed.1003439] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pmed.1003012.].
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18
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Demarest TG, Varma VR, Estrada D, Babbar M, Basu S, Mahajan UV, Moaddel R, Croteau DL, Thambisetty M, Mattson MP, Bohr VA. Biological sex and DNA repair deficiency drive Alzheimer's disease via systemic metabolic remodeling and brain mitochondrial dysfunction. Acta Neuropathol 2020; 140:25-47. [PMID: 32333098 DOI: 10.1007/s00401-020-02152-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 03/22/2020] [Accepted: 03/23/2020] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is an incurable neurodegenerative disease that is more prevalent in women. The increased risk of AD in women is not well understood. It is well established that there are sex differences in metabolism and that metabolic alterations are an early component of AD. We utilized a cross-species approach to evaluate conserved metabolic alterations in the serum and brain of human AD subjects, two AD mouse models, a human cell line, and two Caenorhabditis elegans AD strains. We found a mitochondrial complex I-specific impairment in cortical synaptic brain mitochondria in female, but not male, AD mice. In the hippocampus, Polβ haploinsufficiency caused synaptic complex I impairment in male and female mice, demonstrating the critical role of DNA repair in mitochondrial function. In non-synaptic, glial-enriched, mitochondria from the cortex and hippocampus, complex II-dependent respiration increased in female, but not male, AD mice. These results suggested a glial upregulation of fatty acid metabolism to compensate for neuronal glucose hypometabolism in AD. Using an unbiased metabolomics approach, we consistently observed evidence of systemic and brain metabolic remodeling with a shift from glucose to lipid metabolism in humans with AD, and in AD mice. We determined that this metabolic shift is necessary for cellular and organismal survival in C. elegans, and human cell culture AD models. We observed sex-specific, systemic, and brain metabolic alterations in humans with AD, and that these metabolite changes significantly correlate with amyloid and tau pathology. Among the most significant metabolite changes was the accumulation of glucose-6-phosphate in AD, an inhibitor of hexokinase and rate-limiting metabolite for the pentose phosphate pathway (PPP). Overall, we identified novel mechanisms of glycolysis inhibition, PPP, and tricarboxylic acid cycle impairment, and a neuroprotective augmentation of lipid metabolism in AD. These findings support a sex-targeted metabolism-modifying strategy to prevent and treat AD.
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Affiliation(s)
- Tyler G Demarest
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Vijay R Varma
- Unit of Clinical and Translational Neuroscience, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Darlene Estrada
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Mansi Babbar
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Sambuddha Basu
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Uma V Mahajan
- Unit of Clinical and Translational Neuroscience, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Ruin Moaddel
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Deborah L Croteau
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Madhav Thambisetty
- Unit of Clinical and Translational Neuroscience, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA.
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19
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Roberts JA, Varma VR, Huang CW, An Y, Oommen A, Tanaka T, Ferrucci L, Elango P, Takebayashi T, Harada S, Iida M, Thambisetty M. Blood Metabolite Signature of Metabolic Syndrome Implicates Alterations in Amino Acid Metabolism: Findings from the Baltimore Longitudinal Study of Aging (BLSA) and the Tsuruoka Metabolomics Cohort Study (TMCS). Int J Mol Sci 2020; 21:ijms21041249. [PMID: 32070008 PMCID: PMC7072861 DOI: 10.3390/ijms21041249] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 12/12/2022] Open
Abstract
Rapid lifestyle and dietary changes have contributed to a rise in the global prevalence of metabolic syndrome (MetS), which presents a potential healthcare crisis, owing to its association with an increased burden of multiple cardiovascular and neurological diseases. Prior work has identified the role that genetic, lifestyle, and environmental factors can play in the prevalence of MetS. Metabolomics is an important tool to study alterations in biochemical pathways intrinsic to the pathophysiology of MetS. We undertook a metabolomic study of MetS in serum samples from two ethnically distinct, well-characterized cohorts—the Baltimore Longitudinal Study of Aging (BLSA) from the U.S. and the Tsuruoka Metabolomics Cohort Study (TMCS) from Japan. We used multivariate logistic regression to identify metabolites that were associated with MetS in both cohorts. Among the top 25 most significant (lowest p-value) metabolite associations with MetS in each cohort, we identified 18 metabolites that were shared between TMCS and BLSA, the majority of which were classified as amino acids. These associations implicate multiple biochemical pathways in MetS, including branched-chain amino acid metabolism, glutathione production, aromatic amino acid metabolism, gluconeogenesis, and the tricarboxylic acid cycle. Our results suggest that fundamental alterations in amino acid metabolism may be central features of MetS.
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Affiliation(s)
- Jackson A. Roberts
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (J.A.R.); (V.R.V.)
| | - Vijay R. Varma
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (J.A.R.); (V.R.V.)
| | - Chiung-Wei Huang
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (C.-W.H.); (Y.A.)
| | - Yang An
- Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (C.-W.H.); (Y.A.)
| | - Anup Oommen
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway H91-TK33, Ireland;
| | - Toshiko Tanaka
- Translational Gerontology Branch, National Institute on Aging, NIH, Baltimore, MD 21224, USA; (T.T.); (L.F.); (P.E.)
| | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on Aging, NIH, Baltimore, MD 21224, USA; (T.T.); (L.F.); (P.E.)
| | - Palchamy Elango
- Translational Gerontology Branch, National Institute on Aging, NIH, Baltimore, MD 21224, USA; (T.T.); (L.F.); (P.E.)
| | - Toru Takebayashi
- Department of Preventive Medicine and Public Health, Keio University, Tokyo 160-8282, Japan; (T.T.); (S.H.); (M.I.)
| | - Sei Harada
- Department of Preventive Medicine and Public Health, Keio University, Tokyo 160-8282, Japan; (T.T.); (S.H.); (M.I.)
| | - Miho Iida
- Department of Preventive Medicine and Public Health, Keio University, Tokyo 160-8282, Japan; (T.T.); (S.H.); (M.I.)
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (J.A.R.); (V.R.V.)
- Correspondence: ; Tel.: +1-(410)-558-8572; Fax: +1-(410)-558-8302
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20
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Armstrong NM, Andrews RM, Gross AL, Varma VR, Xue QL, Carlson MC. The association of a novel cognitive frailty index and physical functioning in older at-risk adults. Aging Ment Health 2020; 24:129-136. [PMID: 30668137 PMCID: PMC6646107 DOI: 10.1080/13607863.2018.1531377] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Objectives: Cognitive frailty is a state at the lower end of the continuum of cognitive resilience in which one is at elevated risk for cognitive impairment and dementia. Metrics of a newly developed Cognitive Frailty Index (CFI) were examined for their association with objective functional limitations.Methods: We used baseline data from 607 participants from the Baltimore Experience Corps Trial with measures on the CFI, a computerized Stroop test, and Short Physical Performance Battery (SPPB) score ≤9. Multivariable log-binomial regression models were used to evaluate the associations of CFI metrics (mean reaction time (RT) for total, first-half and second-half trials per condition) with the SPPB. Latent growth models were used to create additional CFI metrics of initial level (intercept) and change (slope) in RT across accurate trials by easy (Color-X) and difficult (Color-Word) conditions. Models were adjusted for race, sex, age, income, major morbidities, depressive symptoms, self-reported health, and Stroop interference (for Color-Word condition only).Results: All CFI RT metrics were associated with SPPB <9, yet latent growth model approaches were most informative. Initial levels of performance on easy (Risk Ratio, [RR] = 1.24; 95% Confidence Interval, [CI]: 1.03, 1.49) and difficult conditions (RR = 1.22; 95% CI: 1.05, 1.41), not rates of learning (slope) (RR = 1.08, 95% CI: 0.81, 1.45 and RR = 1.11, 95% CI: 0.96, 1.27 respectively), were associated with worse physical functioning.Conclusions: The association between the CFI and physical functioning demonstrates the interplay of cognitive frailty and worse objective mobility within a sociodemographic at-risk sample.
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Affiliation(s)
- Nicole M. Armstrong
- Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA
| | - Ryan M. Andrews
- Departments of Mental Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Departments of Biostatistics, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA
| | - Alden L. Gross
- Departments of Mental Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Departments of Epidemiology, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Center on Aging and Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA
| | - Vijay R. Varma
- Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA
| | - Qian-Li Xue
- Departments of Mental Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Departments of Epidemiology, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Center on Aging and Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Division of Geriatric Medicine and Gerontology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michelle C. Carlson
- Departments of Mental Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Departments of Epidemiology, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA,Center on Aging and Health, Johns Hopkins Bloomberg School of Public Health, and Johns Hopkins Center on Aging and Health, Baltimore, MD, USA
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21
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Yasar S, Moored K, Adam A, Zabel F, Chuang YF, Varma VR, Carlson MC. P3-227: ANGIOTENSIN II AND BRAIN VOLUMES IN OLDER ADULTS IN THE BALTIMORE EXPERIENCE CORPS TRIAL (BECT) BRAIN HEALTH STUDY. Alzheimers Dement 2019. [DOI: 10.1016/j.jalz.2019.06.3257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
| | | | - Atif Adam
- Johns Hopkins University; Baltimore MD USA
| | - Fiona Zabel
- Baltimore Polytechnic Institute; Baltimore MD USA
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22
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Yasar S, Varma VR, Harris GC, Carlson MC. Associations of Angiotensin Converting Enzyme-1 and Angiotensin II Blood Levels and Cognitive Function. J Alzheimers Dis 2019; 63:655-664. [PMID: 29660936 DOI: 10.3233/jad-170944] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Emerging evidence suggests a possible role of the renin angiotensin system in the pathophysiologic process of Alzheimer's disease, of which angiotensin converting enzyme-1 (ACE-1) and angiotensin II (ANGII) are important proteins. Few studies evaluated associations between blood ACE-1 and none between ANGII levels, and cognition. OBJECTIVE Our pilot study was aimed to examine associations between blood ACE-1 and ANG II levels and cognitive function in non-demented participants at baseline and over a 1-year period. METHODS 56 participants were included from the Brain Health Substudy of the Baltimore Experience Corps Study. Linear regression analysis, adjusting for confounders, was used to determine associations between baseline ACE-1 and ANGII, and baseline and 1-year follow-up measures of psychomotor and processing speed, executive function, verbal learning memory and working memory, and whether these associations were mediated by blood pressure. RESULTS Participants were predominantly female (75%), African-American (93%), with mean age of 67.8 years and education of 14.3 years. There were no associations between baseline ACE-1 or ANGII levels and cognitive function; however, there were significant association between baseline ACE-1 levels and 1-year follow-up Trail Making Test, Part A (β= 0.003, p = 0.04) and Digit Span (β= -0.001, p = 0.02). CONCLUSIONS In this cognitively intact sample, elevated ACE-1 levels were associated with worse processing speed and working memory after 1 year. Findings from this pilot study suggest that changes in the RAS are associated with alterations in cognitive function warranting further assessment of the role of RAS in neurodegenerative disorders.
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Affiliation(s)
- Sevil Yasar
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Vijay R Varma
- National Institute on Aging, Intramural Research Program, Laboratory of Behavioral Neuroscience, Baltimore, MD, USA
| | | | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
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23
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Seddighi S, Varma VR, An Y, Varma S, Beason-Held LL, Tanaka T, Kitner-Triolo MH, Kraut MA, Davatzikos C, Thambisetty M. SPARCL1 Accelerates Symptom Onset in Alzheimer's Disease and Influences Brain Structure and Function During Aging. J Alzheimers Dis 2018; 61:401-414. [PMID: 29154276 DOI: 10.3233/jad-170557] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We recently reported that alpha-2 macroglobulin (A2M) is a biomarker of neuronal injury in Alzheimer's disease (AD) and identified a network of nine genes co-expressed with A2M in the brain. This network includes the gene encoding SPARCL1, a protein implicated in synaptic maintenance. Here, we examine whether SPARCL1 is associated with longitudinal changes in brain structure and function in older individuals at risk for AD in the Baltimore Longitudinal Study of Aging. Using data from the Gene-Tissue Expression Project, we first identified two single nucleotide polymorphisms (SNPs), rs9998212 and rs7695558, associated with lower brain SPARCL1 gene expression. We then analyzed longitudinal trajectories of cognitive performance in 591 participants who remained cognitively normal (average follow-up interval: 11.8 years) and 129 subjects who eventually developed MCI or AD (average follow-up interval: 9.4 years). Cognitively normal minor allele carriers of rs7695558 who developed incident AD showed accelerated memory loss prior to disease onset. Next, we compared longitudinal changes in brain volumes (MRI; n = 120 participants; follow-up = 6.4 years; 826 scans) and resting-state cerebral blood flow (rCBF; 15O-water PET; n = 81 participants; follow-up = 7.7 years; 664 scans) in cognitively normal participants. Cognitively normal minor allele carriers of rs9998212 showed accelerated atrophy in several global, lobar, and regional brain volumes. Minor allele carriers of both SNPs showed longitudinal changes in rCBF in several brain regions, including those vulnerable to AD pathology. Our findings suggest that SPARCL1 accelerates AD pathogenesis and thus link neuroinflammation with widespread changes in brain structure and function during aging.
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Affiliation(s)
- Sahba Seddighi
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Vijay R Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Yang An
- Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA
| | | | - Lori L Beason-Held
- Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA
| | - Toshiko Tanaka
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA
| | | | - Michael A Kraut
- Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Christos Davatzikos
- Department of Radiology, Center for Biomedical Image Computing and Analytics, University of Pennsylvania, Philadelphia, PA, USA
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
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Varma VR, An Y, Huang CW, Oommenn A, Mueller U, Armstrong N, Davatzikos C, Resnick SM, Thambisetty M. P3‐257: SEX‐SPECIFIC ASSOCIATIONS OF SERUM OXYSTEROLS WITH RISK OF ALZHEIMER'S DISEASE AND RATES OF BRAIN ATROPHY DURING AGING. Alzheimers Dement 2018. [DOI: 10.1016/j.jalz.2018.06.1617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
| | - Yang An
- National Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| | | | | | | | | | - Christos Davatzikos
- Center for Biomedical Image Computing and AnalyticsUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Susan M. Resnick
- National Institute on AgingNational Institutes of HealthBaltimoreMDUSA
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25
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Varma VR, Oommenn A, An Y, Huang CW, Wahrheit J, Pletnikova O, Troncoso JC, O'Brien R, Legido-Quigley C, Resnick SM, Thambisetty M. P2‐276: BRAIN AND BLOOD OXYSTEROL METABOLISM ARE RELATED TO ALZHEIMER'S DISEASE PATHOGENESIS. Alzheimers Dement 2018. [DOI: 10.1016/j.jalz.2018.06.965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
| | | | - Yang An
- National Institute on Aging/National Institutes of Health (NIA/NIH)BaltimoreMDUSA
| | | | | | | | | | | | | | - Susan M. Resnick
- National Institute on Aging/National Institutes of Health (NIA/NIH)BaltimoreMDUSA
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26
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Andrews RM, Tan EJ, Varma VR, Rebok GW, Romani WA, Seeman TE, Gruenewald TL, Tanner EK, Carlson MC. Positive Aging Expectations Are Associated With Physical Activity Among Urban-Dwelling Older Adults. Gerontologist 2018; 57:S178-S186. [PMID: 28854610 DOI: 10.1093/geront/gnx060] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 05/02/2017] [Indexed: 01/18/2023] Open
Abstract
Purpose Regular physical activity is a key component of healthy aging, but few older adults meet physical activity guidelines. Poor aging expectations can contribute to this lack of activity, since negative stereotypes about the aging process can be internalized and affect physical performance. Although prior cross-sectional studies have shown that physical activity and aging expectations are associated, less is known about this association longitudinally, particularly among traditionally underrepresented groups. It is also unclear whether different domains of aging expectations are differentially associated with physical activity. Design and Methods The number of minutes/week of physical activity in which Baltimore Experience Corps Trial participants (N = 446; 92.6% African American) engaged were measured using the CHAMPS questionnaire, while their aging expectations were measured using the ERA-12 survey. Linear mixed effects models assessed the association between physical activity and aging expectations over 2 years, both in full and sex-stratified samples. Separate models were also fit for different ERA-12 domains. Results We found that higher overall expectations regarding aging are associated with higher engagement in moderate- to high-intensity physical activity over a 2-year period of time for women only. When the ERA-12 domains were examined separately, only the physical domain was associated with physical activity, both in women and overall. Implications Low expectations regarding physical aging may represent a barrier to physical activity for older adults. Given that most older adults do not meet recommended physical activity guidelines, identifying factors that improve aging expectations may be a way to increase physical activity levels in aging populations.
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Affiliation(s)
- Ryan M Andrews
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | - Vijay R Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland
| | - George W Rebok
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins School of Medicine, Baltimore, Maryland
| | | | - Teresa E Seeman
- Department of Medicine, Division of Geriatrics, Geffen School of Medicine, University of California, Los Angeles, California
| | - Tara L Gruenewald
- Gerontology Program, Department of Family and Consumer Sciences, California State University, Long Beach, California
| | - Elizabeth K Tanner
- Center on Aging and Health, Johns Hopkins School of Medicine, Baltimore, Maryland.,Department of Community and Public Health, Johns Hopkins University School of Nursing, Baltimore, Maryland
| | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins School of Medicine, Baltimore, Maryland
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Abstract
BACKGROUND Alzheimer's disease (AD) is a neurodegenerative disease that results in severe disability. Very few studies have explored changes in daily physical activity patterns during early stages of AD when components of physical function and mobility may be preserved. OBJECTIVE Our study explored differences in daily physical activity profiles, independent of the effects of non-cognitive factors including physical function and age, among individuals with mild AD compared to controls. METHODS Patients with mild AD and controls (n = 92) recruited from the University of Kansas Alzheimer's Disease Center Registry, wore the Actigraph GT3X+ for seven days, and provided objective physical function (VO2 max) and mobility data. Using multivariate linear regression, we explored whether individuals with mild AD had different daily average and diurnal physical activity patterns compared to controls independent of non-cognitive factors that may affect physical activity, including physical function and mobility. RESULTS We found that mild AD was associated with less moderate-intensity physical activity (p < 0.05), lower peak activity (p < 0.01), and lower physical activity complexity (p < 0.05) particularly during the morning. Mild AD was not associated with greater sedentary activity or less lower-intensity physical activity across the day after adjusting for non-cognitive covariates. CONCLUSIONS These findings suggest that factors independent of physical capacity and mobility may drive declines in moderate-intensity physical activity, and not lower-intensity or sedentary activity, during the early stage of AD. This underscores the importance of a better mechanistic understanding of how cognitive decline and AD pathology impact physical activity. Findings emphasize the potential value of designing and testing time-of-day specific physical activity interventions targeting individuals in the early stages of AD, prior to significant declines in mobility and physical function.
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Affiliation(s)
- Vijay R Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Amber Watts
- Department of Clinical Psychology, University of Kansas, Lawrence, KS, USA
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Varma VR, Oommen AM, Varma S, Casanova R, An Y, Andrews RM, O’Brien R, Pletnikova O, Troncoso JC, Toledo J, Baillie R, Arnold M, Kastenmueller G, Nho K, Doraiswamy PM, Saykin AJ, Kaddurah-Daouk R, Legido-Quigley C, Thambisetty M. Brain and blood metabolite signatures of pathology and progression in Alzheimer disease: A targeted metabolomics study. PLoS Med 2018; 15:e1002482. [PMID: 29370177 PMCID: PMC5784884 DOI: 10.1371/journal.pmed.1002482] [Citation(s) in RCA: 292] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 11/27/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The metabolic basis of Alzheimer disease (AD) is poorly understood, and the relationships between systemic abnormalities in metabolism and AD pathogenesis are unclear. Understanding how global perturbations in metabolism are related to severity of AD neuropathology and the eventual expression of AD symptoms in at-risk individuals is critical to developing effective disease-modifying treatments. In this study, we undertook parallel metabolomics analyses in both the brain and blood to identify systemic correlates of neuropathology and their associations with prodromal and preclinical measures of AD progression. METHODS AND FINDINGS Quantitative and targeted metabolomics (Biocrates AbsoluteIDQ [identification and quantification] p180) assays were performed on brain tissue samples from the autopsy cohort of the Baltimore Longitudinal Study of Aging (BLSA) (N = 44, mean age = 81.33, % female = 36.36) from AD (N = 15), control (CN; N = 14), and "asymptomatic Alzheimer's disease" (ASYMAD, i.e., individuals with significant AD pathology but no cognitive impairment during life; N = 15) participants. Using machine-learning methods, we identified a panel of 26 metabolites from two main classes-sphingolipids and glycerophospholipids-that discriminated AD and CN samples with accuracy, sensitivity, and specificity of 83.33%, 86.67%, and 80%, respectively. We then assayed these 26 metabolites in serum samples from two well-characterized longitudinal cohorts representing prodromal (Alzheimer's Disease Neuroimaging Initiative [ADNI], N = 767, mean age = 75.19, % female = 42.63) and preclinical (BLSA) (N = 207, mean age = 78.68, % female = 42.63) AD, in which we tested their associations with magnetic resonance imaging (MRI) measures of AD-related brain atrophy, cerebrospinal fluid (CSF) biomarkers of AD pathology, risk of conversion to incident AD, and trajectories of cognitive performance. We developed an integrated blood and brain endophenotype score that summarized the relative importance of each metabolite to severity of AD pathology and disease progression (Endophenotype Association Score in Early Alzheimer's Disease [EASE-AD]). Finally, we mapped the main metabolite classes emerging from our analyses to key biological pathways implicated in AD pathogenesis. We found that distinct sphingolipid species including sphingomyelin (SM) with acyl residue sums C16:0, C18:1, and C16:1 (SM C16:0, SM C18:1, SM C16:1) and hydroxysphingomyelin with acyl residue sum C14:1 (SM (OH) C14:1) were consistently associated with severity of AD pathology at autopsy and AD progression across prodromal and preclinical stages. Higher log-transformed blood concentrations of all four sphingolipids in cognitively normal individuals were significantly associated with increased risk of future conversion to incident AD: SM C16:0 (hazard ratio [HR] = 4.430, 95% confidence interval [CI] = 1.703-11.520, p = 0.002), SM C16:1 (HR = 3.455, 95% CI = 1.516-7.873, p = 0.003), SM (OH) C14:1 (HR = 3.539, 95% CI = 1.373-9.122, p = 0.009), and SM C18:1 (HR = 2.255, 95% CI = 1.047-4.855, p = 0.038). The sphingolipid species identified map to several biologically relevant pathways implicated in AD, including tau phosphorylation, amyloid-β (Aβ) metabolism, calcium homeostasis, acetylcholine biosynthesis, and apoptosis. Our study has limitations: the relatively small number of brain tissue samples may have limited our power to detect significant associations, control for heterogeneity between groups, and replicate our findings in independent, autopsy-derived brain samples. CONCLUSIONS We present a novel framework to identify biologically relevant brain and blood metabolites associated with disease pathology and progression during the prodromal and preclinical stages of AD. Our results show that perturbations in sphingolipid metabolism are consistently associated with endophenotypes across preclinical and prodromal AD, as well as with AD pathology at autopsy. Sphingolipids may be biologically relevant biomarkers for the early detection of AD, and correcting perturbations in sphingolipid metabolism may be a plausible and novel therapeutic strategy in AD.
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Affiliation(s)
- Vijay R. Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Anup M. Oommen
- Consilience Research Advisors LLP, Bengaluru, Karnataka, India
| | - Sudhir Varma
- HiThru Analytics, Laurel, Maryland, United States of America
| | - Ramon Casanova
- Department of Biostatistical Science, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Yang An
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
| | - Ryan M. Andrews
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Richard O’Brien
- Department of Neurology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Olga Pletnikova
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Juan C. Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jon Toledo
- Department of Neurology, Houston Methodist Hospital, Houston, Texas, United States of America
| | - Rebecca Baillie
- Rosa & Co LLC, San Carlos, California, United States of America
| | - Matthias Arnold
- Institute of Bioinformatics and Systems Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Gabi Kastenmueller
- Institute of Bioinformatics and Systems Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Kwangsik Nho
- Department of Radiology and Imaging Sciences and the Indiana Alzheimer Disease Center, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - P. Murali Doraiswamy
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, North Carolina, United States of America
- Department of Medicine, Duke University, Durham, North Carolina, United States of America
| | - Andrew J. Saykin
- Department of Radiology and Imaging Sciences and the Indiana Alzheimer Disease Center, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Rima Kaddurah-Daouk
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, North Carolina, United States of America
- Department of Medicine, Duke University, Durham, North Carolina, United States of America
| | | | - Madhav Thambisetty
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, Maryland, United States of America
- * E-mail:
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Affiliation(s)
- Vijay R Varma
- Unit of Clinical and Translational Neuroscience, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, United States.
| | - Debangan Dey
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Andrew Leroux
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Junrui Di
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Jacek Urbanek
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Luo Xiao
- Department of Statistics, North Carolina State University, Raleigh, NC, United States
| | - Vadim Zipunnikov
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
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An Y, Varma VR, Varma S, Casanova R, Dammer E, Pletnikova O, Chia CW, Egan JM, Ferrucci L, Troncoso J, Levey AI, Lah J, Seyfried NT, Legido-Quigley C, O'Brien R, Thambisetty M. Evidence for brain glucose dysregulation in Alzheimer's disease. Alzheimers Dement 2017; 14:318-329. [PMID: 29055815 DOI: 10.1016/j.jalz.2017.09.011] [Citation(s) in RCA: 278] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 07/05/2017] [Accepted: 09/07/2017] [Indexed: 10/18/2022]
Abstract
INTRODUCTION It is unclear whether abnormalities in brain glucose homeostasis are associated with Alzheimer's disease (AD) pathogenesis. METHODS Within the autopsy cohort of the Baltimore Longitudinal Study of Aging, we measured brain glucose concentration and assessed the ratios of the glycolytic amino acids, serine, glycine, and alanine to glucose. We also quantified protein levels of the neuronal (GLUT3) and astrocytic (GLUT1) glucose transporters. Finally, we assessed the relationships between plasma glucose measured before death and brain tissue glucose. RESULTS Higher brain tissue glucose concentration, reduced glycolytic flux, and lower GLUT3 are related to severity of AD pathology and the expression of AD symptoms. Longitudinal increases in fasting plasma glucose levels are associated with higher brain tissue glucose concentrations. DISCUSSION Impaired glucose metabolism due to reduced glycolytic flux may be intrinsic to AD pathogenesis. Abnormalities in brain glucose homeostasis may begin several years before the onset of clinical symptoms.
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Affiliation(s)
- Yang An
- Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Vijay R Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | | | - Ramon Casanova
- Department of Biostatistical Sciences, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Eric Dammer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Olga Pletnikova
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chee W Chia
- Translational Research and Medical Services Section, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Josephine M Egan
- Laboratory of Clinical Investigation, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Luigi Ferrucci
- Longitudinal Studies Section, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Juan Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Allan I Levey
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - James Lah
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - Nicholas T Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | | | - Richard O'Brien
- Department of Neurology, Duke University School of Medicine, Durham, NC, USA
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA.
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Varma VR, Dey D, Leroux A, Di J, Urbanek J, Xiao L, Zipunnikov V. Re-evaluating the effect of age on physical activity over the lifespan. Prev Med 2017; 101:102-108. [PMID: 28579498 PMCID: PMC5541765 DOI: 10.1016/j.ypmed.2017.05.030] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 04/21/2017] [Accepted: 05/28/2017] [Indexed: 11/17/2022]
Abstract
Advancements in accelerometer analytic and visualization techniques allow researchers to more precisely identify and compare critical periods of physical activity (PA) decline by age across the lifespan, and describe how daily PA patterns may vary across age groups. We used accelerometer data from the 2003-2006 cohorts of the National Health and Nutrition Examination Survey (NHANES) (n=12,529) to quantify total PA as well as PA by intensity across the lifespan using sex-stratified, age specific percentile curves constructed using generalized additive models. We additionally estimated minute-to-minute diurnal PA using smoothed bivariate surfaces. We found that from childhood to adolescence (ages 6-19) across sex, PA is sharply lower by age partially due to a later initiation of morning PA. Total PA levels, at age 19 are comparable to levels at age 60. Contrary to prior evidence, during young adulthood (ages 20-30) total and light intensity PA increases by age and then stabilizes during midlife (ages 31-59) partially due to an earlier initiation of morning PA. We additionally found that males compared to females have an earlier lowering in PA by age at midlife and lower total PA, higher sedentary behavior, and lower light intensity PA in older adulthood; these trends seem to be driven by lower PA in the afternoon compared to females. Our results suggest a re-evaluation of how emerging adulthood may affect PA levels and the importance of considering time of day and sex differences when developing PA interventions.
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Affiliation(s)
- Vijay R Varma
- Unit of Clinical and Translational Neuroscience, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, United States.
| | - Debangan Dey
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Andrew Leroux
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Junrui Di
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Jacek Urbanek
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Luo Xiao
- Department of Statistics, North Carolina State University, Raleigh, NC, United States
| | - Vadim Zipunnikov
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
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Hughes TB, Varma VR, Pettigrew C, Albert MS. African Americans and Clinical Research: Evidence Concerning Barriers and Facilitators to Participation and Recruitment Recommendations. Gerontologist 2017; 57:348-358. [PMID: 26553736 PMCID: PMC6075213 DOI: 10.1093/geront/gnv118] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 06/18/2015] [Indexed: 11/14/2022] Open
Abstract
Purpose of the Study The goal of the study was to examine barriers and facilitators to clinical research participation among African Americans, as well as recommendations for overcoming these. Design and Methods Eight focus groups were conducted consisting of 64 individuals. These focus groups targeted 2 groups of individuals: (a) community members, including both individuals involved in research and individuals not involved in research, and (b) community leaders, including clergy, community health care providers and service providers who may influence decisions to participate in research. Results Among participants in both groups, the most common barriers to participation included fear and mistrust of research due to multiple factors, such as a lack of information about research and prevailing knowledge of historical occurrences. Facilitators to research participation included intrinsic factors, such as a desire to help others, and extrinsic factors, such as familiarity with the research recruiter. The focus groups also directly engaged participants in discussions of strategies that might improve recruitment, such as the importance of providing personal stories that enable community members to understand the potential benefits of research. Implications Findings from these focus groups address the mandate from funding agencies that emphasize the importance of including racially diverse populations in clinical research studies, and offer potential solutions for increasing the recruitment and retention of minority participants.
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Affiliation(s)
- Travonia B Hughes
- Department of Pharmacy Practice, Hampton University School of Pharmacy, Hampton, Virginia
| | - Vijay R Varma
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Corinne Pettigrew
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Marilyn S Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Varma VR, Varma S, An Y, Hohman TJ, Seddighi S, Casanova R, Beri A, Dammer EB, Seyfried NT, Pletnikova O, Moghekar A, Wilson MR, Lah JJ, O’Brien RJ, Levey AI, Troncoso JC, Albert MS, Thambisetty M. Alpha-2 macroglobulin in Alzheimer's disease: a marker of neuronal injury through the RCAN1 pathway. Mol Psychiatry 2017; 22:13-23. [PMID: 27872486 PMCID: PMC5726508 DOI: 10.1038/mp.2016.206] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 09/16/2016] [Accepted: 10/11/2016] [Indexed: 12/24/2022]
Abstract
Preclinical changes that precede the onset of symptoms and eventual diagnosis of Alzheimer's disease (AD) are a target for potential preventive interventions. A large body of evidence suggests that inflammation is closely associated with AD pathogenesis and may be a promising target pathway for such interventions. However, little is known about the association between systemic inflammation and preclinical AD pathophysiology. We first examined whether the acute-phase protein, alpha-2 macroglobulin (A2M), a major component of the innate immune system, was associated with cerebrospinal fluid (CSF) markers of neuronal injury in preclinical AD and risk of incident AD in the predictors of cognitive decline among normal individuals (BIOCARD) cohort. We find that A2M concentration in blood is significantly associated with CSF concentrations of the neuronal injury markers, tau and phosphorylated tau, and that higher baseline serum A2M concentration is associated with an almost threefold greater risk of progression to clinical symptoms of AD in men. These findings were replicated in the Alzheimer's Disease Neuroimaging (ADNI) study. Then, utilizing a systems level approach combining large multi-tissue gene expression datasets with mass spectrometry-based proteomic analyses of brain tissue, we identified an A2M gene network that includes regulator of calcineurin (RCAN1), an inhibitor of calcineurin, a well-characterized tau phosphatase. A2M gene and protein expression in the brain were significantly associated with gene and protein expression levels of calcineurin. Collectively these novel findings suggest that A2M is associated with preclinical AD, reflects early neuronal injury in the disease course and may be responsive to tau phosphorylation in the brain through the RCAN1-calcineurin pathway.
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Affiliation(s)
- VR Varma
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - S Varma
- HiThru Analytics, Laurel, MD, USA
| | - Y An
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - TJ Hohman
- Department of Neurology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - S Seddighi
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - R Casanova
- Department of Biostatistical Science, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - A Beri
- Laboratory of Informatics Development (BTRIS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - EB Dammer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - NT Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - O Pletnikova
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - A Moghekar
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - MR Wilson
- School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - JJ Lah
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - RJ O’Brien
- Department of Neurology, Duke University School of Medicine, Durham, NC, USA
| | - AI Levey
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - JC Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - MS Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - M Thambisetty
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
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Varma VR, Hausdorff JM, Studenski SA, Rosano C, Camicioli R, Alexander NB, Chen WG, Lipsitz LA, Carlson MC. Aging, the Central Nervous System, and Mobility in Older Adults: Interventions. J Gerontol A Biol Sci Med Sci 2016; 71:1451-1458. [PMID: 27154905 PMCID: PMC5055648 DOI: 10.1093/gerona/glw080] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 04/12/2016] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Research suggests that the central nervous system (CNS) and mobility are closely linked. CNS-mediated mobility impairment may represent a potentially new and prevalent syndrome within the older adult populations. Interventions targeting this group may have the potential to improve mobility and cognition and prevent disability. METHODS In 2012, the Gerontological Society of America (GSA) and the National Institute on Aging (NIA) sponsored a 3-year conference workshop series, "Aging, the CNS, and Mobility." The goal of this third and final conference was to (i) report on the state of the science of interventions targeting CNS-mediated mobility impairment among community-dwelling older adults and (ii) partnering with the NIA, explore the future of research and intervention design focused on a potentially novel aging syndrome. RESULTS Evidence was presented in five main intervention areas: (i) pharmacology and diet; (ii) exercise; (iii) electrical stimulation; (iv) sensory stimulation/deprivation; and (v) a combined category of multimodal interventions. Workshop participants identified important gaps in knowledge and key recommendations for future interventions related to recruitment and sample selection, intervention design, and methods to measure effectiveness. CONCLUSIONS In order to develop effective preventive interventions for this prevalent syndrome, multidisciplinary teams are essential particularly because of the complex nature of the syndrome. Additionally, integrating innovative methods into the design of interventions may help researchers better measure complex mechanisms, and finally, the value of understanding the link between the CNS and mobility should be conveyed to researchers across disciplines in order to incorporate cognitive and mobility measurements into study protocols.
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Affiliation(s)
- Vijay R Varma
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
- Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD
| | - Jeffrey M Hausdorff
- Center for the Study of Movement, Cognition and Mobility, Neurological Institute, Tel Aviv Sourasky Medical Center, and Department of Physical Therapy, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Israel
| | | | - Caterina Rosano
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pennsylvania
| | - Richard Camicioli
- Department of Medicine, Division of Neurology, University of Alberta, Edmonton, Canada
| | - Neil B Alexander
- Department of Internal Medicine, University of Michigan, Ann Arbor
| | - Wen G Chen
- Division of Neuroscience, National Institute on Aging, Bethesda, Maryland
| | - Lewis A Lipsitz
- Institute for Aging Research, Research, Hebrew Senior Life, Harvard Medical School, Boston, Massachusetts
| | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
- Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
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Abstract
Hippocampal atrophy is a hallmark of Alzheimer's disease pathology, and a target biomarker region for testing intervention efficacy. Over the last few decades, a growing body of evidence from animal and human models suggests that physical activity (PA) is associated with structural benefits to the hippocampus in older adults. Very few human studies, however have explored hippocampal sub-regional specificity of PA; this is significant considering that sub-regions of the hippocampus are associated with distinct cognitive tasks and are differentially affected by disease pathology. This study used objective and self-reported measures of daily walking activity and exercise, and surface-based regional shape analysis using high-field hippocampal sub-regional partitions to explore sub-region specific hippocampal associations in a sample of nondemented, community-dwelling older adults at elevated sociodemographic risk for cognitive decline. Vertex-wise surface areas, which may be more sensitive than global volume measures, were calculated using shape diffeomorphometry, and PA was assessed using step activity monitors and PA questionnaires. We found that daily walking activity in a participant's environment was associated in cross-section mainly with larger surface areas of the subiculum in women. Associations remained significant when controlling for self-reported exercise. Prior studies have found that PA related to exercise and aerobic fitness may be most closely associated with the anterior hippocampus, particularly the dentate gyrus of the hippocampus. These novel findings are the first, to our knowledge, in human models to suggest that PA related to navigation that may not reach the level of moderate-intensity exercise may be associated with specific sub-regions of the hippocampus. These findings underscore the importance of better understanding the independent and related biological mechanisms and pathways by which increasing exercise as well as non-exercise, lifestyle PA may influence structural brain health. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Vijay R Varma
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland.,Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - Xiaoying Tang
- Joint Institute of Engineering, Sun Yat-Sen University-Carnegie Mellon University (SYSU-CMU), Pittsburgh, Pennsylvania, Guangzhou, Guangdong, China.,Shunde International Joint Research Institute, Sun Yat-Sen University-Carnegie Mellon University (SYSU-CMU), Pittsburgh, Pennsylvania, Shunde, Guangdong, China
| | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
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Varma VR, Tan EJ, Gross AL, Harris G, Romani W, Fried LP, Rebok GW, Carlson MC. Effect of Community Volunteering on Physical Activity: A Randomized Controlled Trial. Am J Prev Med 2016; 50:106-110. [PMID: 26340864 PMCID: PMC4691553 DOI: 10.1016/j.amepre.2015.06.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 05/20/2015] [Accepted: 06/18/2015] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Older adults with a high number of chronic conditions and who live in environments that do not promote physical activity have great difficulty initiating and adhering to exercise programs. Novel lifestyle activity interventions that can effectively increase physical activity may address disparities in health in these populations. This study evaluates the effects of the Baltimore Experience Corps program, a community-based volunteer program, on walking activity in older adults. METHODS The Baltimore Experience Corps Trial is a sex-stratified RCT that recruited participants from 2006 to 2009. Older adult participants aged ≥60 years (n=123) were from a nested objective physical activity trial within the larger Baltimore Experience Corps Trial. Participants randomized to the intervention group were placed as volunteers within the Baltimore public school system for 2 years. The primary study outcome was objectively measured total amount of walking activity measured in steps/day. Differences between intervention and control groups were measured at 12 and 24 months using linear mixed effects models. Data were analyzed in 2014. RESULTS At 24 months, women, but not men, in the intervention group showed an increased amount of walking activity, averaging 1,500.3 (95% CI=77.6, 2,922.9) greater steps/day compared with the control group. Women in the control group showed a decline of 1,191.6 (95% CI=-2243.7, -139.5) steps/day at 24 months compared to baseline. CONCLUSIONS A community-based volunteer intervention increased walking activity among older women, who were at elevated risk for both inactivity and adverse health outcomes. TRIAL REGISTRATION This study is registered at www.clinicaltrials.gov NCT00380562.
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Affiliation(s)
- Vijay R Varma
- Johns Hopkins Center on Aging and Health, Baltimore, Maryland; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
| | - Erwin J Tan
- The Corporation for National and Community Service, Washington, District of Columbia
| | - Alden L Gross
- Johns Hopkins Center on Aging and Health, Baltimore, Maryland; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Greg Harris
- Johns Hopkins Center on Aging and Health, Baltimore, Maryland; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | - Linda P Fried
- Mailman School of Public Health, Columbia University, New York, New York
| | - George W Rebok
- Johns Hopkins Center on Aging and Health, Baltimore, Maryland; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Michelle C Carlson
- Johns Hopkins Center on Aging and Health, Baltimore, Maryland; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
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Yasar S, Varma VR, Harris GC, Fedarko N, Carlson MC. P3‐073: Association of angiotensin ii levels with cognition and MRI in older adults in the baltimore experience corps trial (BECT) brain health study. Alzheimers Dement 2015. [DOI: 10.1016/j.jalz.2015.06.940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Varma VR, Chuang YF, Harris GC, Tan EJ, Carlson MC. Low-intensity daily walking activity is associated with hippocampal volume in older adults. Hippocampus 2014; 25:605-15. [PMID: 25483019 DOI: 10.1002/hipo.22397] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2014] [Indexed: 01/12/2023]
Abstract
Hippocampal atrophy is associated with memory impairment and dementia and serves as a key biomarker in the preclinical stages of Alzheimer's disease. Physical activity, one of the most promising behavioral interventions to prevent or delay cognitive decline, has been shown to be associated with hippocampal volume; specifically increased aerobic activity and fitness may have a positive effect on the size of the hippocampus. The majority of older adults, however, are sedentary and have difficulty initiating and maintaining exercise programs. A modestly more active lifestyle may nonetheless be beneficial. This study explored whether greater objectively measured daily walking activity was associated with larger hippocampal volume. We additionally explored whether greater low-intensity walking activity, which may be related to leisure-time physical, functional, and social activities, was associated with larger hippocampal volume independent of exercise and higher-intensity walking activity. Segmentation of hippocampal volumes was performed using Functional Magnetic Resonance Imaging of the Brain's Software Library (FSL), and daily walking activity was assessed using a step activity monitor on 92, nondemented, older adult participants. After controlling for age, education, body mass index, cardiovascular disease risk factors, and the Mini Mental State Exam, we found that a greater amount, duration, and frequency of total daily walking activity were each associated with larger hippocampal volume among older women, but not among men. These relationships were specific to hippocampal volume, compared with the thalamus, used as a control brain region, and remained significant for low-intensity walking activity, independent of moderate- to vigorous-intensity activity and self-reported exercise. This is the first study, to our knowledge, to explore the relationship between objectively measured daily walking activity and hippocampal volume in an older adult population. Findings suggest the importance of examining whether increasing nonexercise, lifestyle physical activities may produce measurable cognitive benefits and affect hippocampal volume through molecular pathways unique to those related to moderate-intensity exercise.
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Affiliation(s)
- Vijay R Varma
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
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Jonassaint CR, Varma VR, Chuang YF, Harris GC, Yasar S, Polinder-Bos H, Carlson MC. Lower hemoglobin is associated with poorer cognitive performance and smaller brain volume in older adults. J Am Geriatr Soc 2014; 62:972-3. [PMID: 24828925 DOI: 10.1111/jgs.12810] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Varma VR, Carlson MC, Parisi JM, Tanner EK, McGill S, Fried LP, Song LH, Gruenewald TL. Experience Corps Baltimore: Exploring the Stressors and Rewards of High-intensity Civic Engagement. Gerontologist 2014; 55:1038-49. [PMID: 24589989 DOI: 10.1093/geront/gnu011] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 01/28/2014] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Experience Corps (EC) represents a high-intensity, intergenerational civic engagement activity where older adults serve as mentors and tutors in elementary schools. Although high-intensity volunteer opportunities are designed to enhance the health and well being of older adult volunteers, little is known about the negative and positive aspects of volunteering unique to intergenerational programs from the volunteer's perspective. DESIGN AND METHODS Stressors and rewards associated with volunteering in EC were explored in 8 focus group discussions with 46 volunteers from EC Baltimore. Transcripts were coded for frequently expressed themes. RESULTS Participants reported stressors and rewards within 5 key domains: intergenerational (children's problem behavior, working with and helping children, observing/facilitating improvement or transformation in a child, and developing a special connection with a child); external to EC (poor parenting and children's social stressors); interpersonal (challenges in working with teachers and bonding/making social connections); personal (enjoyment, self-enhancement/achievement, and being/feeling more active); and structural (satisfaction with the structural elements of the EC program). IMPLICATIONS Volunteers experienced unique intergenerational stressors related to children's problem behavior and societal factors external to the EC program. Overall, intergenerational, interpersonal, and personal rewards from volunteering, as well as program structure may have balanced the stress associated with volunteering. A better understanding of stressors and rewards from high-intensity volunteer programs may enhance our understanding of how intergenerational civic engagement volunteering affects well being in later life and may inform project modifications to maximize such benefits for future volunteers and those they serve.
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Affiliation(s)
- Vijay R Varma
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
| | - Michelle C Carlson
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Jeanine M Parisi
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | - Sylvia McGill
- The Greater Homewood Community Corporation, Baltimore, Maryland
| | - Linda P Fried
- Mailman School of Public Health, Columbia University, New York
| | - Linda H Song
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Tara L Gruenewald
- Davis School of Gerontology, University of Southern California, Los Angeles
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Varma VR, Tan EJ, Wang T, Xue QL, Fried LP, Seplaki CL, King AC, Seeman TE, Rebok GW, Carlson MC. Low-intensity walking activity is associated with better health. J Appl Gerontol 2013; 33:870-87. [PMID: 24652915 DOI: 10.1177/0733464813512896] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Recommended levels of physical activity may represent challenging targets for many older adults at risk for disability, leading to the importance of evaluating whether low-intensity activity is associated with health benefits. We examined the cross-sectional association between low-intensity walking activity (<100 steps/min) and health and physical function in a group of older adults. Participants (N = 187; age = 66.8; 91.4% African American; 76.5% female) wore a StepWatch Activity Monitor to measure components of low-intensity walking activity. Only 7% of participants met physical activity guidelines and moderate-intensity activity (≥100 steps/min) contributed only 10% of the total steps/day and 2% of the total min/day. Greater amount, frequency, and duration of low-intensity activity were associated with better self-report and performance-based measures of physical function, better quality of life, and fewer depressive symptoms (ps < .05). The cross-sectional relationship between low-intensity activity and health outcomes important to independent function suggests that we further explore the longitudinal benefits of low-intensity activity.
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Affiliation(s)
- Vijay R Varma
- Johns Hopkins Center on Aging and Health, Baltimore, MD, USA Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Erwin J Tan
- The Corporation for National and Community Service, Washington, DC, USA
| | - Tao Wang
- Johns Hopkins Center on Aging and Health, Baltimore, MD, USA
| | - Qian-Li Xue
- Johns Hopkins Center on Aging and Health, Baltimore, MD, USA
| | | | | | - Abby C King
- Stanford University School of Medicine, Palo Alto, CA, USA
| | | | - George W Rebok
- Johns Hopkins Center on Aging and Health, Baltimore, MD, USA Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Michelle C Carlson
- Johns Hopkins Center on Aging and Health, Baltimore, MD, USA Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Agbedia OO, Varma VR, Seplaki CL, Seeman TE, Fried LP, Li L, Harris GC, Rebok GW, Xue QL, Tan EJ, Tanner E, Parisi JM, McGill S, Carlson MC. Blunted diurnal decline of cortisol among older adults with low socioeconomic status. Ann N Y Acad Sci 2011; 1231:56-64. [PMID: 21884161 DOI: 10.1111/j.1749-6632.2011.06151.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Low socioeconomic status (SES) is associated with increased risk for adverse health outcomes; those with low SES are thought to experience greater environmental disadvantage and exposure to chronic stress over the life course. The effects of chronic stress on health have been measured by cortisol levels and variations in their diurnal pattern. However, the patterns of association between SES and cortisol have been equivocal in older adults. This paper examined in 98 older adults participating in the Brain Health Substudy of the Baltimore Experience Corps Trial baseline patterns of diurnal variation in salivary cortisol associated with lower versus higher SES using total income and perceived SES relative to others. For each measure, participants stratified into lower versus higher SES showed a more blunted rate of decline in diurnal salivary cortisol over the day in adjusted models (P values ≤ 0.05). There were no SES-related differences in awakening cortisol, cortisol-awakening response, or area under the curve. These findings confirm prior evidence of a biologic pathway through which socioeconomic disadvantage is linked to biologic vulnerability, and through which the impact of volunteer service in Experience Corps may be measured.
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Affiliation(s)
- Owhofasa O Agbedia
- Department of Mental Health & Center on Aging and Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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Arora VK, Varma VR. Pneumonia left lung: an unusual presentation of tropical pulmonary eosinophilia. Indian J Chest Dis Allied Sci 1992; 34:29-32. [PMID: 1521877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- V K Arora
- Department of Tuberculosis and Chest Diseases, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry
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