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Sukreet S, Rafii MS, Rissman RA. From understanding to action: Exploring molecular connections of Down syndrome to Alzheimer's disease for targeted therapeutic approach. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2024; 16:e12580. [PMID: 38623383 PMCID: PMC11016820 DOI: 10.1002/dad2.12580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 03/05/2024] [Accepted: 03/08/2024] [Indexed: 04/17/2024]
Abstract
Down syndrome (DS) is caused by a third copy of chromosome 21. Alzheimer's disease (AD) is a neurodegenerative condition characterized by the deposition of amyloid-beta (Aβ) plaques and neurofibrillary tangles in the brain. Both disorders have elevated Aβ, tau, dysregulated immune response, and inflammation. In people with DS, Hsa21 genes like APP and DYRK1A are overexpressed, causing an accumulation of amyloid and neurofibrillary tangles, and potentially contributing to an increased risk of AD. As a result, people with DS are a key demographic for research into AD therapeutics and prevention. The molecular links between DS and AD shed insights into the underlying causes of both diseases and highlight potential therapeutic targets. Also, using biomarkers for early diagnosis and treatment monitoring is an active area of research, and genetic screening for high-risk individuals may enable earlier intervention. Finally, the fundamental mechanistic parallels between DS and AD emphasize the necessity for continued research into effective treatments and prevention measures for DS patients at risk for AD. Genetic screening with customized therapy approaches may help the DS population in current clinical studies and future biomarkers.
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Affiliation(s)
- Sonal Sukreet
- Department of NeurosciencesUniversity of California‐San DiegoLa JollaCaliforniaUSA
| | - Michael S. Rafii
- Department of Neurology, Alzheimer's Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Robert A. Rissman
- Department of NeurosciencesUniversity of California‐San DiegoLa JollaCaliforniaUSA
- Department Physiology and Neuroscience, Alzheimer’s Therapeutic Research InstituteKeck School of Medicine of the University of Southern CaliforniaSan DiegoCaliforniaUSA
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Stern AM, Van Pelt KL, Liu L, Anderson AK, Ostaszewski B, Mapstone M, O’Bryant S, Petersen ME, Christian BT, Handen BL, Selkoe DJ, Schmitt F, Head E. Plasma NT1-tau and Aβ 42 correlate with age and cognitive function in two large Down syndrome cohorts. Alzheimers Dement 2023; 19:5755-5764. [PMID: 37438872 PMCID: PMC10784408 DOI: 10.1002/alz.13382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 06/09/2023] [Accepted: 06/12/2023] [Indexed: 07/14/2023]
Abstract
INTRODUCTION People with Down syndrome (DS) often develop Alzheimer's disease (AD). Here, we asked whether ultrasensitive plasma immunoassays for a tau N-terminal fragment (NT1-tau) and Aβ isoforms predict cognitive impairment. METHODS Plasma NT1-tau, Aβ37 , Aβ40 , and Aβ42 levels were measured in a longitudinal discovery cohort (N = 85 participants, 220 samples) and a cross-sectional validation cohort (N = 239). We developed linear models and predicted values in the validation cohort. RESULTS Discovery cohort linear mixed models for NT1-tau, Aβ42 , and Aβ37:42 were significant for age; there was no main effect of time. In cross-sectional models, NT1-tau increased and Aβ42 decreased with age. NT1-tau predicted cognitive and functional scores. The discovery cohort linear model for NT1-tau predicted levels in the validation cohort. DISCUSSION NT1-tau correlates with age and worse cognition in DS. Further validation of NT1-tau and other plasma biomarkers of AD neuropathology in DS cohorts is important for clinical utility.
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Affiliation(s)
- Andrew M. Stern
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Kathryn L. Van Pelt
- Sanders-Brown Center for Aging, Department of Neurology, University of Kentucky, Lexington, KY 40508
| | - Lei Liu
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Amirah K. Anderson
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Beth Ostaszewski
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Mark Mapstone
- Department of Neurology, University of California, Irvine, Irvine, CA 92868
| | - Sid O’Bryant
- University of North Texas Health Science Center, Fort Worth, TX 76107
| | | | | | - Benjamin L. Handen
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213
| | - Dennis J. Selkoe
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Frederick Schmitt
- Sanders-Brown Center for Aging, Department of Neurology, University of Kentucky, Lexington, KY 40508
| | - Elizabeth Head
- Department of Pathology and Laboratory Medicine, University of California, Irvine, Irvine, CA 92697
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Nadeau PA, Jobin B, Boller B. Diagnostic Sensitivity and Specificity of Cognitive Tests for Mild Cognitive Impairment and Alzheimer's Disease in Patients with Down Syndrome: A Systematic Review and Meta-Analysis. J Alzheimers Dis 2023; 95:13-51. [PMID: 37522203 DOI: 10.3233/jad-220991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
BACKGROUND Improved health care for people with Down syndrome (DS) has resulted in an increase in their life expectancy therefore increasing comorbidities associated with age-related problems in this population, the most frequent being Alzheimer's disease (AD). To date, several cognitive tests have been developed to evaluate cognitive changes related to the development of mild cognitive impairment (MCI) and AD in people with DS. OBJECTIVE Identify and evaluate available cognitive tests for the diagnosis of MCI and AD in people with DS. METHODS A systematic search of the Pubmed and PsycInfo databases was performed to identify articles published from January 1, 2000 and July 1, 2022. Keysearch terms were DS, AD or MCI, cognition, and assessment. Relevant studies assessing the diagnostic accuracy of cognitive tests for AD or MCI with standard clinical evaluation were extracted. Risk of bias was assessed using the QUADAS 2. RESULTS We identified 15 batteries, 2 intelligence scales, 14 memory tests, 11 executive, functioning tests, 11 motor and visuospatial functioning tests, 5 language tests, 3 attention tests, and 2 orientation tests. Analysis showed that the CAMCOG-DS present a fair to excellent diagnostic accuracy for detecting AD in patients with DS. However, for the diagnosis of MCI, this battery showed poor to good diagnostic accuracy. CONCLUSION The findings highlight important limitations of the current assessment available for the screening of mild cognitive impairment and AD in patients with DS and support the need for more clinical trials to ensure better screening for this highly at-risk population.
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Affiliation(s)
| | - Benoît Jobin
- Université du Québec à Trois-Rivière, Quebec, Canada
| | - Benjamin Boller
- Univerisité de Montréal, Quebec, Canada
- Université du Québec à Trois-Rivière, Quebec, Canada
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Sawa M, Overk C, Becker A, Derse D, Albay R, Weldy K, Salehi A, Beach TG, Doran E, Head E, Yu YE, Mobley WC. Impact of increased APP gene dose in Down syndrome and the Dp16 mouse model. Alzheimers Dement 2022; 18:1203-1234. [PMID: 34757693 PMCID: PMC9085977 DOI: 10.1002/alz.12463] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 06/21/2021] [Accepted: 07/29/2021] [Indexed: 12/24/2022]
Abstract
INTRODUCTION People with Down syndrome (DS) are predisposed to Alzheimer's disease (AD). The amyloid hypothesis informs studies of AD. In AD-DS, but not sporadic AD, increased APP copy number is necessary, defining the APP gene dose hypothesis. Which amyloid precursor protein (APP) products contribute needs to be determined. METHODS Brain levels of full-length protein (fl-hAPP), C-terminal fragments (hCTFs), and amyloid beta (Aβ) peptides were measured in DS, AD-DS, non-demented controls (ND), and sporadic AD cases. The APP gene-dose hypothesis was evaluated in the Dp16 model. RESULTS DS and AD-DS differed from ND and AD for all APP products. In AD-DS, Aβ42 and Aβ40 levels exceeded AD. APP products were increased in the Dp16 model; increased APP gene dose was necessary for loss of vulnerable neurons, tau pathology, and activation of astrocytes and microglia. DISCUSSION Increases in APP products other than Aβ distinguished AD-DS from AD. Deciphering AD-DS pathogenesis necessitates deciphering which APP products contribute and how.
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Affiliation(s)
- Mariko Sawa
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624
| | - Cassia Overk
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624
| | - Ann Becker
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624
| | - Dominique Derse
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624
| | - Ricardo Albay
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624
| | - Kim Weldy
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624
| | - Ahmad Salehi
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305
| | - Thomas G. Beach
- Brain and Body Donation Program, Banner Sun Health Research Institute, Sun City, AZ 85351
| | - Eric Doran
- Department of Pediatrics, University of California, Irvine, CA, 92697
| | - Elizabeth Head
- Department of Pathology & Laboratory Medicine, University of California, Irvine, CA, 92697
| | - Y. Eugene Yu
- The Children’s Guild Foundation Down Syndrome Research Program, Genetics and Genomics Program, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14263
| | - William C Mobley
- Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093-0624,Correspondence to: William Mobley M.D., Department of Neurosciences, UCSD School of Medicine, 9500 Gilman Drive, GPL 355, La Jolla, CA 92093-0624;
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Ashford JW, Schmitt FA, Bergeron MF, Bayley PJ, Clifford JO, Xu Q, Liu X, Zhou X, Kumar V, Buschke H, Dean M, Finkel SI, Hyer L, Perry G. Now is the Time to Improve Cognitive Screening and Assessment for Clinical and Research Advancement. J Alzheimers Dis 2022; 87:305-315. [DOI: 10.3233/jad-220211] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Alzheimer’s disease (AD) is the only cause of death ranked in the top ten globally without precise early diagnosis or effective means of prevention or treatment. Further, AD was identified as a pandemic [1] well before COVID-19 was dubbed a 21st century pandemic [2]. And now, with the realization of the prominent secondary impacts of pandemics, there is a growing, widespread recognition of the tremendous magnitude of the impending burden from AD in an aging world population in the coming decades [3]. This appreciation has amplified the growing and pressing need for a new, efficacious, and practical platform to detect and track cognitive decline, beginning in the preliminary (prodromal) phases of the disease, sensitively, accurately, effectively, reliably, efficiently, and remotely [4–7]. Moreover, the parallel necessity of clarifying and understanding risk factors, developing successful prevention strategies [8–17], and discovering and monitoring viable and effective treatments could all benefit from accurate and efficient screening and assessment platforms. Modern recognition of AD [18] as a common affliction of the elderly began in 1968 with a paper by Blessed, Tomlinson, & Roth [19] in which two tests, one a brief assessment of cognitive function and the other a measure of daily function, demonstrated impairment which was associated with the postmortem counts of neurofibrillary tangles, composed mainly of microtubule-associated protein-tau (tau), in the brain, though not to senile plaques, composed mainly of amyloid-β (Aβ). Even in more recent analyses, the tangles correspond with the severity of dementia more than the plaques [20, 21]. Since 1960, a plethora of cognitive tests, paper and pencil [22, 23], simple screening models [24], and computerized [25–27], have been developed to assess the dysfunction associated with AD. However, there has been limited application of Modern Test Theory, which includes Item Characteristic Curve Analysis, used in the technological development of such tools [28–31], along with widespread failure to understand the underlying AD pathological process to guide test development [32, 33]. The lack of such development has likely been a major contributor to the failure of the field to develop timely screening approaches for AD [34, 35], inaccurate assessment of the progression of AD [36], and even now, failure to find an effective approach to stopping AD.
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Affiliation(s)
- J. Wesson Ashford
- War Related Illness and Injury Study Center, VA Palo Alto HCS, Palo Alto, CA, USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
| | - Frederick A. Schmitt
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
- Departments of Neurology, Psychiatry, Neurosurgery, Psychology, Behavioral Science; Sanders-Brown Center on Aging, Spinal Cord & Brain Injury Research Center, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, USA
| | | | - Peter J. Bayley
- War Related Illness and Injury Study Center, VA Palo Alto HCS, Palo Alto, CA, USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
| | | | - Qun Xu
- Health Management Center, Department of Neurology, Renji Hospital of Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaolei Liu
- Department of Neurology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
- Yunnan Provincial Clinical Research Center for Neurological Diseases, Yunnan, China
| | - Xianbo Zhou
- Center for Alzheimer’s Research, Washington Institute of Clinical Research, Vienna, VA, USA
- Zhongze Therapeutics, Shanghai, China
| | | | - Herman Buschke
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
- The Saul R. Korey Department of Neurology and Dominick P. Purpura Department of Neuroscience, Lena and Joseph Gluck Distinguished Scholar in Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Margaret Dean
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
- Geriatric Division, Internal Medicine, Texas Tech Health Sciences Center, Amarillo, TX, USA
| | - Sanford I. Finkel
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
- University of Chicago Medical School, Chicago, IL, USA
| | - Lee Hyer
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
- Gateway Behavioral Health, Mercer University, School of Medicine, Savannah, GA, USA
| | - George Perry
- Medical, Scientific, Memory Screening Advisory Board, Alzheimer’s Foundation of American (AFA), New York, USA
- Brain Health Consortium, Department Biology and Chemistry, University of Texas at San Antonio, San Antonio, TX, USA
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Fully automated chemiluminescence enzyme immunoassays showing high correlation with immunoprecipitation mass spectrometry assays for β-amyloid (1-40) and (1-42) in plasma samples. Biochem Biophys Res Commun 2021; 576:22-26. [PMID: 34478915 DOI: 10.1016/j.bbrc.2021.08.066] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/16/2021] [Accepted: 08/23/2021] [Indexed: 11/24/2022]
Abstract
Blood based β-amyloid (Aβ) assays that can predict amyloid positivity in the brain are in high demand. Current studies that utilize immunoprecipitation mass spectrometry assay (IP-MS), which has high specificity for measuring analytes, have revealed that precise plasma Aβ assays have the potential to detect amyloid positivity in the brain. In this study, we developed plasma Aβ40 and Aβ42 immunoassays using a fully automated immunoassay platform that is used in routine clinical practice. Our assays showed high sensitivity (limit of quantification: 2.46 pg/mL [Aβ40] and 0.16 pg/mL [Aβ42]) and high reproducibility within-run (coefficients of variation [CVs]: <3.7% [Aβ40] and <2.0% [Aβ42]) and within-laboratory (CVs: <4.6% [Aβ40] and <5.3% [Aβ42]). The interference from plasma components was less than 10%, and the cross-reactivity with various lengths of Aβ peptides was less than 0.5%. In addition, we found a significant correlation between the IP-MS method and our immunoassay (correlation coefficients of Pearson's r: 0.91 [Aβ40] and 0.82 [Aβ42]). Our new method to quantify plasma Aβ40 and Aβ42 provides clinicians and patients with a way to continuously monitor disease progression.
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Rujeedawa T, Carrillo Félez E, Clare ICH, Fortea J, Strydom A, Rebillat AS, Coppus A, Levin J, Zaman SH. The Clinical and Neuropathological Features of Sporadic (Late-Onset) and Genetic Forms of Alzheimer's Disease. J Clin Med 2021; 10:4582. [PMID: 34640600 PMCID: PMC8509365 DOI: 10.3390/jcm10194582] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 12/17/2022] Open
Abstract
The purpose of this review is to compare and highlight the clinical and pathological aspects of genetic versus acquired Alzheimer's disease: Down syndrome-associated Alzheimer's disease in (DSAD) and Autosomal Dominant Alzheimer's disease (ADAD) are compared with the late-onset form of the disease (LOAD). DSAD and ADAD present in a younger population and are more likely to manifest with non-amnestic (such as dysexecutive function features) in the prodromal phase or neurological features (such as seizures and paralysis) especially in ADAD. The very large variety of mutations associated with ADAD explains the wider range of phenotypes. In the LOAD, age-associated comorbidities explain many of the phenotypic differences.
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Affiliation(s)
- Tanzil Rujeedawa
- Cambridge Intellectual & Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge CB2 8PQ, UK; (T.R.); (E.C.F.); (I.C.H.C.)
| | - Eva Carrillo Félez
- Cambridge Intellectual & Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge CB2 8PQ, UK; (T.R.); (E.C.F.); (I.C.H.C.)
| | - Isabel C. H. Clare
- Cambridge Intellectual & Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge CB2 8PQ, UK; (T.R.); (E.C.F.); (I.C.H.C.)
- Cambridgeshire and Peterborough Foundation NHS Trust, Fulbourn CB21 5EF, UK
| | - Juan Fortea
- Sant Pau Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Biomedical Research Institute Sant Pau, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain;
- Center of Biomedical Investigation Network for Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain
- Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, 08029 Barcelona, Spain
| | - Andre Strydom
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK;
- South London and the Maudsley NHS Foundation Trust, The LonDowns Consortium, London SE5 8AZ, UK
| | | | - Antonia Coppus
- Department for Primary and Community Care, Department of Primary and Community Care (149 ELG), Radboud University Nijmegen Medical Center, P.O. Box 9101, 6525 GA Nijmegen, The Netherlands;
| | - Johannes Levin
- Department of Neurology, Ludwig-Maximilians-Universität München, 80539 Munich, Germany;
- German Center for Neurodegenerative Diseases, Feodor-Lynen-Strasse 17, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Strasse 17, 81377 Munich, Germany
| | - Shahid H. Zaman
- Cambridge Intellectual & Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge CB2 8PQ, UK; (T.R.); (E.C.F.); (I.C.H.C.)
- Cambridgeshire and Peterborough Foundation NHS Trust, Fulbourn CB21 5EF, UK
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Koychev I, Jansen K, Dette A, Shi L, Holling H. Blood-Based ATN Biomarkers of Alzheimer's Disease: A Meta-Analysis. J Alzheimers Dis 2021; 79:177-195. [PMID: 33252080 DOI: 10.3233/jad-200900] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The Amyloid Tau Neurodegeneration (ATN) framework was proposed to define the biological state underpinning Alzheimer's disease (AD). Blood-based biomarkers offer a scalable alternative to the costly and invasive currently available biomarkers. OBJECTIVE In this meta-analysis we sought to assess the diagnostic performance of plasma amyloid (Aβ40, Aβ42, Aβ42/40 ratio), tangle (p-tau181), and neurodegeneration (total tau [t-tau], neurofilament light [NfL]) biomarkers. METHODS Electronic databases were screened for studies reporting biomarker concentrations for AD and control cohorts. Biomarker performance was examined by random-effect meta-analyses based on the ratio between biomarker concentrations in patients and controls. RESULTS 83 studies published between 1996 and 2020 were included in the analyses. Aβ42/40 ratio as well as Aβ42 discriminated AD patients from controls when using novel platforms such as immunomagnetic reduction (IMR). We found significant differences in ptau-181 concentration for studies based on single molecule array (Simoa), but not for studies based on IMR or ELISA. T-tau was significantly different between AD patients and control in IMR and Simoa but not in ELISA-based studies. In contrast, NfL differentiated between groups across platforms. Exosome studies showed strong separation between patients and controls for Aβ42, t-tau, and p-tau181. CONCLUSION Currently available assays for sampling plasma ATN biomarkers appear to differentiate between AD patients and controls. Novel assay methodologies have given the field a significant boost for testing these biomarkers, such as IMR for Aβ, Simoa for p-tau181. Enriching samples through extracellular vesicles shows promise but requires further validation.
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Affiliation(s)
- Ivan Koychev
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Katrin Jansen
- Department of Psychology, University of Münster, Münster, Germany
| | - Alina Dette
- Department of Psychology, University of Münster, Münster, Germany
| | - Liu Shi
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Heinz Holling
- Department of Psychology, University of Münster, Münster, Germany
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Toshikawa H, Ikenaka A, Li L, Nishinaka-Arai Y, Niwa A, Ashida A, Kazuki Y, Nakahata T, Tamai H, Russell DW, Saito MK. N-Acetylcysteine prevents amyloid-β secretion in neurons derived from human pluripotent stem cells with trisomy 21. Sci Rep 2021; 11:17377. [PMID: 34462463 PMCID: PMC8405674 DOI: 10.1038/s41598-021-96697-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 08/10/2021] [Indexed: 11/09/2022] Open
Abstract
Down syndrome (DS) is caused by the trisomy of chromosome 21. Among the many disabilities found in individuals with DS is an increased risk of early-onset Alzheimer's disease (AD). Although higher oxidative stress and an upregulation of amyloid β (Aβ) peptides from an extra copy of the APP gene are attributed to the AD susceptibility, the relationship between the two factors is unclear. To address this issue, we established an in vitro cellular model using neurons differentiated from DS patient-derived induced pluripotent stem cells (iPSCs) and isogenic euploid iPSCs. Neurons differentiated from DS patient-derived iPSCs secreted more Aβ compared to those differentiated from the euploid iPSCs. Treatment of the neurons with an antioxidant, N-acetylcysteine, significantly suppressed the Aβ secretion. These findings suggest that oxidative stress has an important role in controlling the Aβ level in neurons differentiated from DS patient-derived iPSCs and that N-acetylcysteine can be a potential therapeutic option to ameliorate the Aβ secretion.
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Affiliation(s)
- Hiromitsu Toshikawa
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.,Osaka Medical and Pharmaceutical University, Takatsuki, 5690801, Japan.,Social Welfare Organization "SAISEIKAI" Imperial Gift Foundation Inc., Saiseikai Suita Hospital, Suita, 5640013, Japan
| | - Akihiro Ikenaka
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Li Li
- Division of Hematology, School of Medicine, University of Washington, Seattle, WA, 98195, USA
| | - Yoko Nishinaka-Arai
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.,Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 6068507, Japan
| | - Akira Niwa
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Akira Ashida
- Osaka Medical and Pharmaceutical University, Takatsuki, 5690801, Japan
| | - Yasuhiro Kazuki
- Chromosome Engineering Research Center, Tottori University, Tottori, Japan.,Division of Genome and Cellular Functions, Department of Molecular and Cellular Biology, School of Life Science, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Tatsutoshi Nakahata
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hiroshi Tamai
- Osaka Medical and Pharmaceutical University, Takatsuki, 5690801, Japan.,Institute for Developmental Brain Research, Osaka Medical and Pharmaceutical University, Takatsuki, 5690801, Japan
| | - David W Russell
- Division of Hematology, School of Medicine, University of Washington, Seattle, WA, 98195, USA
| | - Megumu K Saito
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.
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Handen B, Clare I, Laymon C, Petersen M, Zaman S, O’Bryant S, Minhas D, Tudorascu D, Brown S, Christian B. Acute Regression in Down Syndrome. Brain Sci 2021; 11:1109. [PMID: 34439728 PMCID: PMC8391552 DOI: 10.3390/brainsci11081109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Acute regression has been reported in some individuals with Down syndrome (DS), typically occurring between the teenage years and mid to late 20s. Characterized by sudden, and often unexplained, reductions in language skills, functional living skills and reduced psychomotor activity, some individuals have been incorrectly diagnosed with Alzheimer's disease (AD). METHODS This paper compares five individuals with DS who previously experienced acute regression with a matched group of 15 unaffected individuals with DS using a set of AD biomarkers. RESULTS While the sample was too small to conduct statistical analyses, findings suggest there are possible meaningful differences between the groups on proteomics biomarkers (e.g., NfL, total tau). Hippocampal, caudate and putamen volumes were slightly larger in the regression group, the opposite of what was hypothesized. A slightly lower amyloid load was found on the PET scans for the regression group, but no differences were noted on tau PET. CONCLUSIONS Some proteomics biomarker findings suggest that individuals with DS who experience acute regression may be at increased risk for AD at an earlier age in comparison to unaffected adults with DS. However, due to the age of the group (mean 38 years), it may be too early to observe meaningful group differences on image-based biomarkers.
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Affiliation(s)
- Benjamin Handen
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15260, USA; (C.L.); (D.M.); (D.T.)
| | - Isabel Clare
- Department of Psychiatry, University of Cambridge, Cambridge CB2 1TN, UK; (I.C.); (S.Z.); (S.B.)
| | - Charles Laymon
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15260, USA; (C.L.); (D.M.); (D.T.)
| | - Melissa Petersen
- Department of Family Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (M.P.); (S.O.)
| | - Shahid Zaman
- Department of Psychiatry, University of Cambridge, Cambridge CB2 1TN, UK; (I.C.); (S.Z.); (S.B.)
| | - Sid O’Bryant
- Department of Family Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (M.P.); (S.O.)
| | - Davneet Minhas
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15260, USA; (C.L.); (D.M.); (D.T.)
| | - Dana Tudorascu
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15260, USA; (C.L.); (D.M.); (D.T.)
| | - Stephanie Brown
- Department of Psychiatry, University of Cambridge, Cambridge CB2 1TN, UK; (I.C.); (S.Z.); (S.B.)
| | - Bradley Christian
- Departments of Medical Physics and Psychiatry, University of Wisconsin, Madison, WI 53706, USA;
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11
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Montoliu-Gaya L, Strydom A, Blennow K, Zetterberg H, Ashton NJ. Blood Biomarkers for Alzheimer's Disease in Down Syndrome. J Clin Med 2021; 10:3639. [PMID: 34441934 PMCID: PMC8397053 DOI: 10.3390/jcm10163639] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/09/2021] [Accepted: 08/12/2021] [Indexed: 12/15/2022] Open
Abstract
Epidemiological evidence suggests that by the age of 40 years, all individuals with Down syndrome (DS) have Alzheimer's disease (AD) neuropathology. Clinical diagnosis of dementia by cognitive assessment is complex in these patients due to the pre-existing and varying intellectual disability, which may mask subtle declines in cognitive functioning. Cerebrospinal fluid (CSF) and positron emission tomography (PET) biomarkers, although accurate, are expensive, invasive, and particularly challenging in such a vulnerable population. The advances in ultra-sensitive detection methods have highlighted blood biomarkers as a valuable and realistic tool for AD diagnosis. Studies with DS patients have proven the potential blood-based biomarkers for sporadic AD (amyloid-β, tau, phosphorylated tau, and neurofilament light chain) to be useful in this population. In addition, biomarkers related to other pathologies that could aggravate dementia progression-such as inflammatory dysregulation, energetic imbalance, or oxidative stress-have been explored. This review serves to provide a brief overview of the main findings from the limited neuroimaging and CSF studies, outline the current state of blood biomarkers to diagnose AD in patients with DS, discuss possible past limitations of the research, and suggest considerations for developing and validating blood-based biomarkers in the future.
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Affiliation(s)
- Laia Montoliu-Gaya
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, 431 41 Mölndal, Sweden; (K.B.); (H.Z.); (N.J.A.)
| | - Andre Strydom
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London WC2R 2LS, UK;
- South London and Maudsley NHS Foundation Trust, London SE5 8AZ, UK
- London Down Syndrome Consortium (LonDowns), London, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, 431 41 Mölndal, Sweden; (K.B.); (H.Z.); (N.J.A.)
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 413 45 Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, 431 41 Mölndal, Sweden; (K.B.); (H.Z.); (N.J.A.)
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 413 45 Mölndal, Sweden
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
- UK Dementia Research Institute, University College London, London WC1E 6BT, UK
- Hong Kong Center for Neurodegenerative Diseases, Hong Kong, China
| | - Nicholas James Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, 431 41 Mölndal, Sweden; (K.B.); (H.Z.); (N.J.A.)
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Old Age Psychiatry, Maurice Wohl Clinical Neuroscience Institute, King’s College London, London SE5 9RT, UK
- NIHR Biomedical Research Centre for Mental Health, Biomedical Research Unit for Dementia at South London, Maudsley NHS Foundation, London SE5 8AF, UK
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12
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Screening of Cognitive Changes in Adults with Intellectual Disabilities: A Systematic Review. Brain Sci 2020; 10:brainsci10110848. [PMID: 33198271 PMCID: PMC7698112 DOI: 10.3390/brainsci10110848] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 11/30/2022] Open
Abstract
Background and Aims: Screening and assessment of cognitive changes in adults with Intellectual Disabilities (ID), mainly Down Syndrome (DS), is crucial to offer appropriate services to their needs. We present a systematic review of the existing instruments assessing dementia, aiming to support researchers and clinicians’ best practice. Methods: Searches were carried out in the databases Web of Science; PubMed; PsycINFO in March 2019 and updated in October 2020. Studies were selected and examined if they: (1) focused on assessing age-related cognitive changes in persons with ID; (2) included adults and/or older adults; (3) included scales and batteries for cognitive assessment. Results: Forty-eight cross-sectional studies and twenty-seven longitudinal studies were selected representing a total sample of 6451 participants (4650 DS and 1801 with other ID). In those studies, we found 39 scales, questionnaires, and inventories, and 13 batteries for assessing cognitive and behavioural changes in adults with DS and other ID. Conclusion: The most used instrument completed by an informant or carer was the Dementia Questionnaire for Learning Disabilities (DLD), and its previous versions. We discuss the strengths and limitations of the instruments and outline recommendations for future use.
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13
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Rafii MS, Ances BM, Schupf N, Krinsky‐McHale SJ, Mapstone M, Silverman W, Lott I, Klunk W, Head E, Christian B, Lai F, Rosas HD, Zaman S, Petersen ME, Strydom A, Fortea J, Handen B, O'Bryant S. The AT(N) framework for Alzheimer's disease in adults with Down syndrome. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2020; 12:e12062. [PMID: 33134477 PMCID: PMC7588820 DOI: 10.1002/dad2.12062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 06/04/2020] [Indexed: 12/15/2022]
Abstract
The National Institute on Aging in conjunction with the Alzheimer's Association (NIA-AA) recently proposed a biological framework for defining the Alzheimer's disease (AD) continuum. This new framework is based upon the key AD biomarkers (amyloid, tau, neurodegeneration, AT[N]) instead of clinical symptoms and represents the latest understanding that the pathological processes underlying AD begin decades before the manifestation of symptoms. By using these same biomarkers, individuals with Down syndrome (DS), who are genetically predisposed to developing AD, can also be placed more precisely along the AD continuum. The A/T(N) framework is therefore thought to provide an objective manner by which to select and enrich samples for clinical trials. This new framework is highly flexible and allows the addition of newly confirmed AD biomarkers into the existing AT(N) groups. As biomarkers for other pathological processes are validated, they can also be added to the AT(N) classification scheme, which will allow for better characterization and staging of AD in DS. These biological classifications can then be merged with clinical staging for an examination of factors that impact the biological and clinical progression of the disease. Here, we leverage previously published guidelines for the AT(N) framework to generate such a plan for AD among adults with DS.
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Affiliation(s)
- Michael S. Rafii
- Alzheimer's Therapeutic Research Institute (ATRI)Keck School of MedicineUniversity of Southern CaliforniaSan DiegoCaliforniaUSA
| | - Beau M. Ances
- Center for Advanced Medicine NeuroscienceWashington University School of Medicine in St. LouisSt. LouisMissouriUSA
| | - Nicole Schupf
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain/G.H. Sergievsky CenterColumbia University Irving Medical CenterNew YorkNew YorkUSA
- Department of EpidemiologyMailman School of Public HealthColumbia UniversityNew YorkNew YorkUSA
- Department of NeurologyNeurological Institute of New York, Columbia University Irving Medical CenterNew YorkNew YorkUSA
- Department of PsychiatryColumbia University Medical CenterNew YorkNew YorkUSA
| | - Sharon J. Krinsky‐McHale
- Department of PsychologyNYS Institute for Basic Research in Developmental DisabilitiesStaten IslandNew YorkUSA
| | - Mark Mapstone
- Department of NeurologyUniversity of CaliforniaIrvineCaliforniaUSA
| | - Wayne Silverman
- Department of PediatricsSchool of MedicineUniversity of CaliforniaIrvineCaliforniaUSA
| | - Ira Lott
- Department of PediatricsSchool of MedicineUniversity of CaliforniaIrvineCaliforniaUSA
| | - William Klunk
- Department of PsychiatryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Elizabeth Head
- Department of PathologyGillespie Neuroscience Research Facility, University of CaliforniaIrvineCaliforniaUSA
| | - Brad Christian
- Department of Medical Physics and PsychiatryUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Florence Lai
- Department of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMassachusettsUSA
| | - H. Diana Rosas
- Departments of Neurology and RadiologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMassachusettsUSA
| | - Shahid Zaman
- Department of PsychiatrySchool of Clinical MedicineUniversity of CambridgeCambridgeUK
- Cambridgeshire and Peterborough NHS Foundation TrustFulbourn HospitalCambridgeUK
| | - Melissa E. Petersen
- Department of Family Medicine and Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Andre Strydom
- Department of Forensic and Neurodevelopmental SciencesInstitute of Psychiatry, Psychology and NeuroscienceKing's College LondonLondonUK
| | - Juan Fortea
- Sant Pau Memory UnitDepartment of NeurologyHospital de la Santa Creu i Sant PauBiomedical Research Institute Sant PauUniversitat Autònoma de BarcelonaBarcelonaSpain
| | - Benjamin Handen
- Department of PsychiatryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Sid O'Bryant
- Institute for Translational Research and Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
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14
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Sae-Lee W, Scott LL, Brose L, Encarnacion AJ, Shi T, Kore P, Oyibo LO, Ye C, Rozmiarek SK, Pierce JT. APP-Induced Patterned Neurodegeneration Is Exacerbated by APOE4 in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2020; 10:2851-2861. [PMID: 32580938 PMCID: PMC7407474 DOI: 10.1534/g3.120.401486] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/19/2020] [Indexed: 11/18/2022]
Abstract
Genetic and epidemiological studies have found that variations in the amyloid precursor protein (APP) and the apoliopoprotein E (APOE) genes represent major modifiers of the progressive neurodegeneration in Alzheimer's disease (AD). An extra copy of or gain-of-function mutations in APP correlate with early onset AD. Compared to the other variants (APOE2 and APOE3), the ε4 allele of APOE (APOE4) hastens and exacerbates early and late onset forms of AD. Convenient in vivo models to study how APP and APOE4 interact at the cellular and molecular level to influence neurodegeneration are lacking. Here, we show that the nematode C. elegans can model important aspects of AD including age-related, patterned neurodegeneration that is exacerbated by APOE4 Specifically, we found that APOE4, but not APOE3, acts with APP to hasten and expand the pattern of cholinergic neurodegeneration caused by APP Molecular mechanisms underlying how APP and APOE4 synergize to kill some neurons while leaving others unaffected may be uncovered using this convenient worm model of neurodegeneration.
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Affiliation(s)
- Wisath Sae-Lee
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Luisa L Scott
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Lotti Brose
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Aliyah J Encarnacion
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Ted Shi
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Pragati Kore
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Lashaun O Oyibo
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Congxi Ye
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Susan K Rozmiarek
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
| | - Jonathan T Pierce
- Center for Learning and Memory; Waggoner Center for Alcohol and Addiction Research; Cell and Molecular Biology; Department of Neuroscience, The University of Texas at Austin, TX, 78712
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15
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Mapstone M, Gross TJ, Macciardi F, Cheema AK, Petersen M, Head E, Handen BL, Klunk WE, Christian BT, Silverman W, Lott IT, Schupf N. Metabolic correlates of prevalent mild cognitive impairment and Alzheimer's disease in adults with Down syndrome. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2020; 12:e12028. [PMID: 32258359 PMCID: PMC7131985 DOI: 10.1002/dad2.12028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 02/14/2020] [Accepted: 02/19/2020] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Disruption of metabolic function is a recognized feature of late onset Alzheimer's disease (LOAD). We sought to determine whether similar metabolic pathways are implicated in adults with Down syndrome (DS) who have increased risk for Alzheimer's disease (AD). METHODS We examined peripheral blood from 292 participants with DS who completed baseline assessments in the Alzheimer's Biomarkers Consortium-Down Syndrome (ABC-DS) using untargeted mass spectrometry (MS). Our sample included 38 individuals who met consensus criteria for AD (DS-AD), 43 who met criteria for mild cognitive impairment (DS-MCI), and 211 who were cognitively unaffected and stable (CS). RESULTS We measured relative abundance of 8,805 features using MS and 180 putative metabolites were differentially expressed (DE) among the groups at false discovery rate-corrected q< 0.05. From the DE features, a nine-feature classifier model classified the CS and DS-AD groups with receiver operating characteristic area under the curve (ROC AUC) of 0.86 and a two-feature model classified the DS-MCI and DS-AD groups with ROC AUC of 0.88. Metabolite set enrichment analysis across the three groups suggested alterations in fatty acid and carbohydrate metabolism. DISCUSSION Our results reveal metabolic alterations in DS-AD that are similar to those seen in LOAD. The pattern of results in this cross-sectional DS cohort suggests a dynamic time course of metabolic dysregulation which evolves with clinical progression from non-demented, to MCI, to AD. Metabolomic markers may be useful for staging progression of DS-AD.
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Affiliation(s)
- Mark Mapstone
- Department of NeurologyUniversity of California‐IrvineIrvineCaliforniaUSA
| | - Thomas J Gross
- Department of NeurologyUniversity of California‐IrvineIrvineCaliforniaUSA
| | - Fabio Macciardi
- Department of Psychiatry and Human BehaviorUniversity of California‐IrvineIrvineCaliforniaUSA
| | - Amrita K Cheema
- Departments of Biochemistry and Molecular & Cellular BiologyGeorgetown University Medical CenterWashingtonDCUSA
| | - Melissa Petersen
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Elizabeth Head
- Department of Pathology and Laboratory MedicineUniversity of California‐IrvineIrvineCaliforniaUSA
| | - Benjamin L Handen
- Department of PsychiatryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - William E Klunk
- Department of PsychiatryUniversity of PittsburghPittsburghPennsylvaniaUSA
- Department of NeurologyUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Bradley T Christian
- Departments of Medical Physics and PsychiatryWaisman CenterUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Wayne Silverman
- Department of PediatricsUniversity of California‐ IrvineIrvineCaliforniaUSA
| | - Ira T Lott
- Department of PediatricsUniversity of California‐ IrvineIrvineCaliforniaUSA
| | - Nicole Schupf
- Taub Institute for Research in Alzheimer's Disease and the Aging BrainColumbia UniversityNew YorkNew YorkUSA
- Department of NeurologyColumbia University and the New York Presbyterian HospitalNew YorkNew YorkUSA
- Department of EpidemiologyJoseph P. Mailman School of Public HealthColumbia UniversityNew YorkNew YorkUSA
- Gertrude H. Sergievsky CenterColumbia UniversityNew YorkNew YorkUSA
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16
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Du Y, Chen L, Jiao Y, Cheng Y. Cerebrospinal fluid and blood Aβ levels in Down syndrome patients with and without dementia: a meta-analysis study. Aging (Albany NY) 2019; 11:12202-12212. [PMID: 31860872 PMCID: PMC6949072 DOI: 10.18632/aging.102560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 11/20/2019] [Indexed: 12/30/2022]
Abstract
Abnormal β-amyloid (Aβ) levels were found in patients with Down syndrome (DS). However, Aβ levels in patients with DS and DS with dementia (DSD) vary considerably across studies. Therefore, we performed a systematic literature review and quantitatively summarized the clinical Aβ data on the cerebrospinal fluid (CSF) and blood of patients with DS and those with DSD using a meta-analytical technique. We performed a systematic search of the PubMed and Web of Science and identified 27 studies for inclusion in the meta-analysis. Random-effects meta-analysis indicated that the levels of blood Aβ1-40 and Aβ1-42 were significantly elevated in patients with DS compared with those in healthy control (HC) subjects. In contrast, there were no significant differences between patients with DS and those with DSD in the blood Aβ1-40 and Aβ1-42 levels. The CSF Aβ1-42 levels were significantly decreased in patients with DS compared to those in HC subjects. Further, CSF Aβ1-42 levels were significantly decreased in patients with DSD compared to those with DS, with a large effect size. Taken together, our results demonstrated that blood Aβ1-40 and Aβ1-42 levels were significantly increased in patients with DS while CSF Aβ1-42, but not Aβ1-40 levels were significantly decreased in patients with DS.
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Affiliation(s)
- Yang Du
- Center on Translational Neuroscience, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Lei Chen
- Center on Translational Neuroscience, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Yuguo Jiao
- Center on Translational Neuroscience, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Yong Cheng
- Center on Translational Neuroscience, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
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17
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Manzano-Crespo M, Atienza M, Cantero JL. Lower serum expression of miR-181c-5p is associated with increased plasma levels of amyloid-beta 1-40 and cerebral vulnerability in normal aging. Transl Neurodegener 2019; 8:34. [PMID: 31700619 PMCID: PMC6827222 DOI: 10.1186/s40035-019-0174-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 09/25/2019] [Indexed: 12/11/2022] Open
Abstract
Background Previous studies have shown that expression levels of miR-181c are downregulated by amyloid-β (Aβ) deposition and chronic cerebral hypoperfusion, both factors largely associated with the development of AD. Moreover, reduced 2-[18F]fluoro-2-deoxy-D-glucose (FDG)-PET brain metabolism and volume loss of regions of the medial temporal lobe have been generally recognized as hallmarks of AD. Based on this evidence, we have here investigated potential associations between serum levels of miR-181c-5p and these AD signatures in asymptomatic elderly subjects. Methods Ninety-five normal elderly subjects underwent clinical, cognitive, structural MRI, and FDG-PET explorations. Serum expression levels of miR-181c-5p and plasma Aβ concentrations were further analyzed in this cohort. Regression analyses were performed to assess associations between serum miR-181c-5p levels and cognitive functioning, plasma Aβ, structural and metabolic brain changes. Results Decreased serum expression of miR-181c-5p was associated with increased plasma levels of Aβ1–40, deficits in cortical glucose metabolism, and volume reduction of the entorhinal cortex. No significant associations were found between lower miR-181c-5p levels and cognitive deficits or cortical thinning. Conclusions These findings suggest that deregulation of serum miR-181c-5p may indicate cerebral vulnerability in late life.
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Affiliation(s)
- Marta Manzano-Crespo
- 1Laboratory of Functional Neuroscience, Pablo de Olavide University, Ctra. de Utrera Km 1, 41013 Seville, Spain
| | - Mercedes Atienza
- 1Laboratory of Functional Neuroscience, Pablo de Olavide University, Ctra. de Utrera Km 1, 41013 Seville, Spain.,2CIBERNED, Network Center for Biomedical Research in Neurodegenerative Diseases, 28031, Madrid, Spain
| | - Jose L Cantero
- 1Laboratory of Functional Neuroscience, Pablo de Olavide University, Ctra. de Utrera Km 1, 41013 Seville, Spain.,2CIBERNED, Network Center for Biomedical Research in Neurodegenerative Diseases, 28031, Madrid, Spain
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18
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Ivanov R, Zamyatin V, Klimenko A, Matushkin Y, Savostyanov A, Lashin S. Reconstruction and Analysis of Gene Networks of Human Neurotransmitter Systems Reveal Genes with Contentious Manifestation for Anxiety, Depression, and Intellectual Disabilities. Genes (Basel) 2019; 10:genes10090699. [PMID: 31514272 PMCID: PMC6770977 DOI: 10.3390/genes10090699] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/06/2019] [Accepted: 09/09/2019] [Indexed: 12/28/2022] Open
Abstract
Background: The study of the biological basis of anxiety, depression, and intellectual disabilities in humans is one of the most actual problems of modern neurophysiology. Of particular interest is the study of complex interactions between molecular genetic factors, electrophysiological properties of the nervous system, and the behavioral characteristics of people. The neurobiological understanding of neuropsychiatric disorders requires not only the identification of genes that play a role in the molecular mechanisms of the occurrence and course of diseases, but also the understanding of complex interactions that occur between these genes. A systematic study of such interactions obviously contributes to the development of new methods of diagnosis, prevention, and treatment of disorders, as the orientation to allele variants of individual loci is not reliable enough, because the literature describes a number of genes, the same alleles of which can be associated with different, sometimes extremely different variants of phenotypic traits, depending on the genetic background, of their carriers, habitat, and other factors. Results: In our study, we have reconstructed a series of gene networks (in the form of protein–protein interactions networks, as well as networks of transcription regulation) to build a model of the influence of complex interactions of environmental factors and genetic risk factors for intellectual disability, depression, and other disorders in human behavior. Conclusion: A list of candidate genes whose expression is presumably associated with environmental factors and has potentially contentious manifestation for behavioral and neurological traits is identified for further experimental verification.
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Affiliation(s)
- Roman Ivanov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia.
- Novosibirsk State University, 630090 Novosibirsk, Russia.
| | - Vladimir Zamyatin
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia.
- Novosibirsk State University, 630090 Novosibirsk, Russia.
| | - Aleksandra Klimenko
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia.
- Novosibirsk State University, 630090 Novosibirsk, Russia.
| | - Yury Matushkin
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia.
- Novosibirsk State University, 630090 Novosibirsk, Russia.
| | - Alexander Savostyanov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia.
- Novosibirsk State University, 630090 Novosibirsk, Russia.
- Institute of Physiology and Basic Medicine SB RAMS, 630117 Novosibirsk, Russia.
| | - Sergey Lashin
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia.
- Novosibirsk State University, 630090 Novosibirsk, Russia.
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19
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Alhajraf F, Ness D, Hye A, Strydom A. Plasma amyloid and tau as dementia biomarkers in Down syndrome: Systematic review and meta-analyses. Dev Neurobiol 2019; 79:684-698. [PMID: 31389176 PMCID: PMC6790908 DOI: 10.1002/dneu.22715] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 08/02/2019] [Accepted: 08/02/2019] [Indexed: 12/18/2022]
Abstract
Individuals with Down syndrome (DS) are at high risk of developing Alzheimer's disease (AD). Discovering reliable biomarkers which could facilitate early AD diagnosis and be used to predict/monitor disease course would be extremely valuable. To examine if analytes in blood related to amyloid plaques may constitute such biomarkers, we conducted meta‐analyses of studies comparing plasma amyloid beta (Aβ) levels between DS individuals and controls, and between DS individuals with and without dementia. PubMed, Embase, and Google Scholar were searched for studies investigating the relationship between Aβ plasma concentrations and dementia in DS and 10 studies collectively comprising >1,600 adults, including >1,400 individuals with DS, were included. RevMan 5.3 was used to perform meta‐analyses. Meta‐analyses showed higher plasma Aβ40 (SMD = 1.79, 95% CI [1.14, 2.44], Z = 5.40, p < .00001) and plasma Aβ42 levels (SMD = 1.41, 95% CI [1.15, 1.68], Z = 10.46, p < .00001) in DS individuals than controls, and revealed that DS individuals with dementia had higher plasma Aβ40 levels (SMD = 0.23, 95% CI [0.05, 0.41], Z = 2.54, p = .01) and lower Aβ42/Aβ40 ratios (SMD = −0.33, 95% CI [−0.63, −0.03], Z = 2.15, p = .03) than DS individuals without dementia. Our results indicate that plasma Aβ40 levels may constitute a promising biomarker for predicting dementia status in individuals with DS. Further investigations using new ultra‐sensitive assays are required to obtain more reliable results and to investigate to what extent these results may be generalizable beyond the DS population.
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Affiliation(s)
- Falah Alhajraf
- UCL Queen Square Institute of Neurology, University College London, London, UK.,Al Amiri Hospital, Kuwait City, State of Kuwait
| | - Deborah Ness
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.,The LonDownS Consortium (London Down Syndrome Consortium), London, UK
| | - Abdul Hye
- The Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Andre Strydom
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.,The LonDownS Consortium (London Down Syndrome Consortium), London, UK
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20
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Carmona-Iragui M, Videla L, Lleó A, Fortea J. Down syndrome, Alzheimer disease, and cerebral amyloid angiopathy: The complex triangle of brain amyloidosis. Dev Neurobiol 2019; 79:716-737. [PMID: 31278851 DOI: 10.1002/dneu.22709] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 05/04/2019] [Accepted: 07/02/2019] [Indexed: 11/07/2022]
Abstract
Down syndrome (DS) is the main genetic cause of intellectual disability worldwide. The overexpression of the Amyloid Precursor Protein, present in chromosome 21, leads to β-amyloid deposition that results in Alzheimer disease (AD) and, in most cases, also to cerebral amyloid angiopathy (CAA) neuropathology. People with DS invariably develop the neuropathological hallmarks of AD at the age of 40, and they are at an ultra high risk for suffering AD-related cognitive impairment thereafter. In the general population, cerebrovascular disease is a significant contributor to AD-related cognitive impairment, while in DS remains understudied. This review describes the current knowledge on cerebrovascular disease in DS and reviews the potential biomarkers that could be useful in the future studies, focusing on CAA. We also discuss available evidence on sporadic AD or other genetically determined forms of AD. We highlight the urgent need of large biomarker-characterized cohorts, including neuropathological correlations, to study the exact contribution of CAA and related vascular factors that play a role in cognition and occur with aging, their characterization and interrelationships. DS represents a unique context in which to perform these studies as this population is relatively protected from some conventional vascular risk factors and they develop significant CAA, DS represents a particular atheroma-free model to study AD-related vascular pathologies. Only deepening on these underlying mechanisms, new preventive and therapeutic strategies could be designed to improve the quality of life of this population and their caregivers and lead to new avenues of treatment also in the general AD population.
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Affiliation(s)
- María Carmona-Iragui
- Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau- Biomedical Research Institute Sant Pau- Universitat Autònoma de Barcelona, Barcelona, Spain
- Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, Barcelona, Spain
- Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Laura Videla
- Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau- Biomedical Research Institute Sant Pau- Universitat Autònoma de Barcelona, Barcelona, Spain
- Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, Barcelona, Spain
- Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Alberto Lleó
- Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau- Biomedical Research Institute Sant Pau- Universitat Autònoma de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Juan Fortea
- Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau- Biomedical Research Institute Sant Pau- Universitat Autònoma de Barcelona, Barcelona, Spain
- Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, Barcelona, Spain
- Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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21
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Petersen ME, O’Bryant S. Blood-based biomarkers for Down syndrome and Alzheimer's disease: A systematic review. Dev Neurobiol 2019; 79:699-710. [PMID: 31389185 PMCID: PMC8284928 DOI: 10.1002/dneu.22714] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/01/2019] [Accepted: 08/01/2019] [Indexed: 12/20/2022]
Abstract
Down syndrome (DS) occurs due to triplication of chromosome 21. Individuals with DS face an elevated risk for development of Alzheimer's disease (AD) due to increased amyloid beta (Aβ) resulting from the over-expression of the amyloid precursor protein found on chromosome 21. Diagnosis of AD among individuals with DS poses particular challenges resulting in an increased focus on alternative diagnostic methods such as blood-based biomarkers. The aim of this review was to evaluate the current state of the literature of blood-based biomarkers found in individuals with DS and particularly among those also diagnosed with AD or in prodromal stages (mild cognitive impairment [MCI]). A systematic review was conducted utilizing a comprehensive search strategy. Twenty-four references were identified, of those, 22 fulfilled inclusion criteria were selected for further analysis with restriction to only plasma-based biomarkers. Studies found Aβ to be consistently higher among individuals with DS; however, the link between Aβ peptides (Aβ1-42 and Aβ1-40) and AD among DS was inconsistent. Inflammatory-based proteins were more reliably found to be elevated leading to preliminary work focused on an algorithmic approach with predominantly inflammatory-based proteins to detect AD and MCI as well as predict risk of incidence among DS. Separate work has also shown remarkable diagnostic accuracy with the use of a single protein (NfL) as compared to combined proteomic profiles. This review serves to outline the current state of the literature and highlights the potential plasma-based biomarkers for use in detecting AD and MCI among this at-risk population.
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Affiliation(s)
- Melissa E. Petersen
- University of Texas MD Anderson Cancer Center, Department of Neuro-Oncology, Houston, Texas USA
| | - Sid O’Bryant
- University of North Texas Health Science Center, Department of Pharmacology & Neuroscience, Fort Worth, Texas, USA,Address correspondence to: Sid E. O’Bryant, Ph.D., University of North Texas Health Science Center, Institute for Translational Research3500 Camp Bowie Blvd, Fort Worth, TX 76107. Phone: (817) 735-2963; Fax: (817) 735-0611;
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de França Bram JM, Talib LL, Joaquim HPG, Carvalho CL, Gattaz WF, Forlenza OV. Alzheimer’s Disease-related Biomarkers in Aging Adults with Down Syndrome: Systematic Review. CURRENT PSYCHIATRY RESEARCH AND REVIEWS 2019. [DOI: 10.2174/1573400515666190122152855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Background:
Down syndrome (DS) is associated with a high prevalence of cognitive
impairment and dementia in middle age and older adults. Given the presence of common neuropathological
findings and similar pathogenic mechanisms, dementia in DS is regarded as a form of
genetically determined, early-onset AD. The clinical characterization of cognitive decline in persons
with DS is a difficult task, due to the presence intellectual disability and pre-existing cognitive impairment.
Subtle changes that occur at early stages of the dementing process may not be perceived
clinically, given that most cognitive screening tests are not sensitive enough to detect them. Therefore,
biological markers will provide support to the diagnosis of DS-related cognitive impairment
and dementia, particularly at early stages of this process.
Objective:
To perform a systematic review of the literature on AD-related biomarkers in DS.
Method:
We searched PubMed, Web of Science and Cochrane Library for scientific papers published
between 2008 and 2018 using as primary mesh terms ‘Down’, ‘Alzheimer’, ‘biomarker’.
Results:
79 studies were retrieved, and 39 were considered eligible for inclusion in the systematic
review: 14 post-mortem studies, 10 neuroimaging, 4 addressing cerebrospinal fluid biomarkers, and
11 on peripheral markers.
Conclusion:
There is consistent growth in the number of publication in this field over the past years.
Studies in DS-related dementia tend to incorporate many of the diagnostic technologies that have
been more extensively studied and validated in AD. In many instances, the study of CNS and peripheral
biomarkers reinforces the presence of AD pathology in DS.
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Affiliation(s)
- Jessyka Maria de França Bram
- Laboratorio de Neurociencias (LIM-27), Departamento e Instituto de Psiquiatria, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Leda Leme Talib
- Laboratorio de Neurociencias (LIM-27), Departamento e Instituto de Psiquiatria, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Helena Passarelli Giroud Joaquim
- Laboratorio de Neurociencias (LIM-27), Departamento e Instituto de Psiquiatria, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Cláudia Lopes Carvalho
- Laboratorio de Neurociencias (LIM-27), Departamento e Instituto de Psiquiatria, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Wagner Farid Gattaz
- Laboratorio de Neurociencias (LIM-27), Departamento e Instituto de Psiquiatria, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Orestes Vicente Forlenza
- Laboratorio de Neurociencias (LIM-27), Departamento e Instituto de Psiquiatria, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
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23
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Fonseca LM, Mattar GP, Haddad GG, Gonçalves AS, Miguel ADQC, Guilhoto LM, Zaman S, Holland AJ, Bottino CMDC, Hoexter MQ. Frontal-subcortical behaviors during Alzheimer's disease in individuals with Down syndrome. Neurobiol Aging 2019; 78:186-194. [PMID: 30947114 DOI: 10.1016/j.neurobiolaging.2019.02.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 02/08/2019] [Accepted: 02/28/2019] [Indexed: 11/25/2022]
Abstract
There is evidence that frontal-subcortical circuits play an important role in the initial presentation of dementia in Down syndrome (DS), including changes in behavior, a decline in working memory and executive dysfunction. We evaluated 92 individuals with DS (≥30 years of age), divided into 3 groups by diagnosis-stable cognition, prodromal dementia, and Alzheimer's disease. Each individual was evaluated with an executive protocol developed for people with intellectual disabilities and was rated for behaviors related to frontal lobe dysfunction (disinhibition, executive dysfunction, and apathy) by an informant using the Frontal Systems Behavior Scale. Informant-reported behaviors related to frontal lobe dysfunction were found to correlate negatively with executive function performance. Disinhibition and executive dysfunction were associated with the clinical stage of dementia. The odds of having Alzheimer's disease increased in parallel with increases in the domain and total Frontal Systems Behavior Scale scores (p ≤ 0.5). Disinhibition, executive dysfunction and apathy should be taken into consideration during the clinical evaluation of adults with DS, and future studies should consider the intersection of neuropathology, brain connectivity, and behavior.
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Affiliation(s)
- Luciana Mascarenhas Fonseca
- Old Age Research Group, PROTER, Department and Institute of Psychiatry, University of São Paulo School of Medicine, FMUSP, São Paulo, Brazil; Cambridge Intellectual and Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge, UK.
| | - Guilherme Prado Mattar
- Old Age Research Group, PROTER, Department and Institute of Psychiatry, University of São Paulo School of Medicine, FMUSP, São Paulo, Brazil
| | - Glenda Guerra Haddad
- Old Age Research Group, PROTER, Department and Institute of Psychiatry, University of São Paulo School of Medicine, FMUSP, São Paulo, Brazil
| | - Aline Souza Gonçalves
- Laboratory of Neuroscience, LIM27, Department and Institute of Psychiatry, University of São Paulo School of Medicine, FMUSP, São Paulo, Brazil
| | | | - Laura Maria Guilhoto
- Association of Parents and Friends of Individuals with Intellectual Disability of São Paulo, São Paulo, Brazil; Department of Neurology and Neurosurgery, Federal University of Sao Paulo, São Paulo, Brazil
| | - Shahid Zaman
- Cambridge Intellectual and Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Anthony J Holland
- Cambridge Intellectual and Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Cassio Machado de Campos Bottino
- Old Age Research Group, PROTER, Department and Institute of Psychiatry, University of São Paulo School of Medicine, FMUSP, São Paulo, Brazil
| | - Marcelo Queiroz Hoexter
- Obsessive-Compulsive Spectrum Disorders Program, PROTOC, Department and Institute of Psychiatry, University of São Paulo School of Medicine, FMUSP, São Paulo, Brazil
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24
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Startin CM, Ashton NJ, Hamburg S, Hithersay R, Wiseman FK, Mok KY, Hardy J, Lleó A, Lovestone S, Parnetti L, Zetterberg H, Hye A, Strydom A. Plasma biomarkers for amyloid, tau, and cytokines in Down syndrome and sporadic Alzheimer's disease. Alzheimers Res Ther 2019; 11:26. [PMID: 30902060 PMCID: PMC6429702 DOI: 10.1186/s13195-019-0477-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 02/21/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Down syndrome (DS), caused by chromosome 21 trisomy, is associated with an ultra-high risk of dementia due to Alzheimer's disease (AD), driven by amyloid precursor protein (APP) gene triplication. Understanding relevant molecular differences between those with DS, those with sporadic AD (sAD) without DS, and controls will aid in understanding AD development in DS. We explored group differences in plasma concentrations of amyloid-β peptides and tau (as their accumulation is a characteristic feature of AD) and cytokines (as the inflammatory response has been implicated in AD development, and immune dysfunction is common in DS). METHODS We used ultrasensitive assays to compare plasma concentrations of the amyloid-β peptides Aβ40 and Aβ42, total tau (t-tau), and the cytokines IL1β, IL10, IL6, and TNFα between adults with DS (n = 31), adults with sAD (n = 27), and controls age-matched to the group with DS (n = 27), and explored relationships between molecular concentrations and with age within each group. In the group with DS, we also explored relationships with neurofilament light (NfL) concentration, due to its potential use as a biomarker for AD in DS. RESULTS Aβ40, Aβ42, and IL1β concentrations were higher in DS, with a higher Aβ42/Aβ40 ratio in controls. The group with DS showed moderate positive associations between concentrations of t-tau and both Aβ42 and IL1β. Only NfL concentration in the group with DS showed a significant positive association with age. CONCLUSIONS Concentrations of Aβ40 and Aβ42 were much higher in adults with DS than in other groups, reflecting APP gene triplication, while no difference in the Aβ42/Aβ40 ratio between those with DS and sAD may indicate similar processing and deposition of Aβ40 and Aβ42 in these groups. Higher concentrations of IL1β in DS may reflect an increased vulnerability to infections and/or an increased prevalence of autoimmune disorders, while the positive association between IL1β and t-tau in DS may indicate IL1β is associated with neurodegeneration. Finally, NfL concentration may be the most suitable biomarker for dementia progression in DS. The identification of such a biomarker is important to improve the detection of dementia and monitor its progression, and for designing clinical intervention studies.
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Affiliation(s)
- Carla M. Startin
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, 16 De Crespigny Park, London, SE5 8AF UK
- Division of Psychiatry, University College London, London, UK
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
| | - Nicholas J. Ashton
- Maurice Wohl Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
- NIHR Biomedical Research Centre for Mental Health, Biomedical Research Unit for Dementia at South London, and Maudsley NHS Foundation, London, UK
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Wallenberg Centre for Molecular & Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Sarah Hamburg
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, 16 De Crespigny Park, London, SE5 8AF UK
- Division of Psychiatry, University College London, London, UK
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
| | - Rosalyn Hithersay
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, 16 De Crespigny Park, London, SE5 8AF UK
- Division of Psychiatry, University College London, London, UK
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
| | - Frances K. Wiseman
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
- Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
| | - Kin Y. Mok
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
- Division of Life Science, Hong Kong University of Science and Technology, Hong Kong, SAR People’s Republic of China
| | - John Hardy
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
- Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK
- Reta Lila Weston Institute, Institute of Neurology, University College London, London, UK
| | - Alberto Lleó
- Memory Unit, Neurology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | | | - Lucilla Parnetti
- Centre for Memory Disturbances, Laboratory of Clinical Neurochemistry, Section of Neurology, Department of Medicine, University of Perugia, Perugia, Italy
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- UK Dementia Research Institute at UCL, London, UK
| | - Abdul Hye
- Maurice Wohl Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
- NIHR Biomedical Research Centre for Mental Health, Biomedical Research Unit for Dementia at South London, and Maudsley NHS Foundation, London, UK
| | - André Strydom
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, 16 De Crespigny Park, London, SE5 8AF UK
- Division of Psychiatry, University College London, London, UK
- The LonDownS Consortium (London Down Syndrome Consortium), London, UK
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25
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Abstract
Down syndrome (DS; Trisomy 21) is the most common chromosomal disorder in humans. It has numerous associated neurologic phenotypes including intellectual disability, sleep apnea, seizures, behavioral problems, and dementia. With improved access to medical care, people with DS are living longer than ever before. As more individuals with DS reach old age, the necessity for further life span research is essential and cannot be overstated. There is currently a scarcity of information on common medical conditions encountered as individuals with DS progress into adulthood and old age. Conflicting information and uncertainty about the relative risk of dementia for adults with DS is a source of distress for the DS community that creates a major obstacle to proper evaluation and treatment. In this chapter, we discuss the salient neurologic phenotypes of DS, including Alzheimer's disease (AD), and current understanding of their biologic bases and management.
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Affiliation(s)
- Michael S Rafii
- Department of Neurology, Keck School of Medicine of the University of Southern California, San Diego, CA, United States
| | | | - Mariko Sawa
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States
| | - William C Mobley
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States.
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26
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Fortea J, Carmona-Iragui M, Benejam B, Fernández S, Videla L, Barroeta I, Alcolea D, Pegueroles J, Muñoz L, Belbin O, de Leon MJ, Maceski AM, Hirtz C, Clarimón J, Videla S, Delaby C, Lehmann S, Blesa R, Lleó A. Plasma and CSF biomarkers for the diagnosis of Alzheimer's disease in adults with Down syndrome: a cross-sectional study. Lancet Neurol 2018; 17:860-869. [DOI: 10.1016/s1474-4422(18)30285-0] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/12/2018] [Accepted: 07/13/2018] [Indexed: 12/15/2022]
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27
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Gary C, Hérard AS, Hanss Z, Dhenain M. Plasma Amyloid Is Associated with White Matter and Subcortical Alterations and Is Modulated by Age and Seasonal Rhythms in Mouse Lemur Primates. Front Aging Neurosci 2018; 10:35. [PMID: 29491833 PMCID: PMC5817060 DOI: 10.3389/fnagi.2018.00035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 01/30/2018] [Indexed: 01/03/2023] Open
Abstract
Accumulation of amyloid-β (Aβ) peptides in the brain is a critical early event in the pathogenesis of Alzheimer's disease (AD), the most common age-related neurodegenerative disorder. There is increasing interest in measuring levels of plasma Aβ since this could help in diagnosis of brain pathology. However, the value of plasma Aβ in such a diagnosis is still controversial and factors modulating its levels are still poorly understood. The mouse lemur (Microcebus murinus) is a primate model of cerebral aging which can also present with amyloid plaques and whose Aβ is highly homologous to humans'. In an attempt to characterize this primate model and to evaluate the potential of plasma Aβ as a biomarker for brain alterations, we measured plasma Aβ40 concentration in 21 animals aged from 5 to 9.5 years. We observed an age-related increase in plasma Aβ40 levels. We then evaluated the relationships between plasma Aβ40 levels and cerebral atrophy in these mouse lemurs. Voxel-based analysis of cerebral MR images (adjusted for the age/sex/brain size of the animals), showed that low Aβ40 levels are associated with atrophy of several white matter and subcortical brain regions. These results suggest that low Aβ40 levels in middle-aged/old animals are associated with brain deterioration. One special feature of mouse lemurs is that their metabolic and physiological parameters follow seasonal changes strictly controlled by illumination. We evaluated seasonal-related variations of plasma Aβ40 levels and found a strong effect, with higher plasma Aβ40 concentrations in winter conditions compared to summer. This question of seasonal modulation of Aβ plasma levels should be addressed in clinical studies. We also focused on the amplitude of the difference between plasma Aβ40 levels during the two seasons and found that this amplitude increases with age. Possible mechanisms leading to these seasonal changes are discussed.
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Affiliation(s)
- Charlotte Gary
- Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Neurodegenerative Diseases Laboratory, Fontenay-aux-Roses, France.,Commissariat à l'Energie Atomique et aux Energies Alternatives, Direction de la Recherche Fondamentale, Institut François Jacob, MIRCen, Fontenay-aux-Roses, France
| | - Anne-Sophie Hérard
- Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Neurodegenerative Diseases Laboratory, Fontenay-aux-Roses, France.,Commissariat à l'Energie Atomique et aux Energies Alternatives, Direction de la Recherche Fondamentale, Institut François Jacob, MIRCen, Fontenay-aux-Roses, France
| | - Zoé Hanss
- Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Neurodegenerative Diseases Laboratory, Fontenay-aux-Roses, France.,Commissariat à l'Energie Atomique et aux Energies Alternatives, Direction de la Recherche Fondamentale, Institut François Jacob, MIRCen, Fontenay-aux-Roses, France
| | - Marc Dhenain
- Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Neurodegenerative Diseases Laboratory, Fontenay-aux-Roses, France.,Commissariat à l'Energie Atomique et aux Energies Alternatives, Direction de la Recherche Fondamentale, Institut François Jacob, MIRCen, Fontenay-aux-Roses, France
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28
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Zis P, Strydom A. Clinical aspects and biomarkers of Alzheimer's disease in Down syndrome. Free Radic Biol Med 2018; 114:3-9. [PMID: 28870521 PMCID: PMC6451620 DOI: 10.1016/j.freeradbiomed.2017.08.024] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 08/28/2017] [Accepted: 08/30/2017] [Indexed: 12/31/2022]
Abstract
Alzheimer's disease (AD) may affect in excess of 90% of individuals with Down syndrome (DS) after age 60, due to duplication of the APP gene in trisomy of chromosome 21, with neuropathology that is comparable to Sporadic AD and Familial AD (FAD). Previous literature suggested some unique features in clinical presentation of dementia in DS (DSd), which might be due to diagnostic difficulties, or represent a real difference compared to SAD or FAD. We review current knowledge on clinical diagnosis and presentation of dementia in DS in comparison with FAD due to APP mutations and APP duplication. We suggest that the clinical presentation in DS (prominent memory decline and behavioral symptoms, and early development of myoclonus and seizures) are similar to the clinical features associated with APP mutations that is known to have an increased Aβ42/ Aβ40 ratio, and highlight the relative lack of vascular complications associated with cerebral amyloid angiopathy in DS in comparison with those rare individuals with FAD due to duplication APP. We consider the biomarker evidence associated with DS and DSd with reference to Aβ peptide levels and oxidative stress, and suggest future directions for research to explore the potential mechanisms associated with the clinical presentation of DSd.
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Affiliation(s)
- Panagiotis Zis
- Academic Department of Neurosciences, Sheffield Teaching Hospitals NHS Foundation Trust, UK
| | - Andre Strydom
- Division of Psychiatry, University College London, London, UK; Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neurosciences, King's College London, London, UK; The LonDownS Consortium, London, UK.
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29
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Fonseca LM, Yokomizo JE, Bottino CM, Fuentes D. Frontal Lobe Degeneration in Adults with Down Syndrome and Alzheimer's Disease: A Review. Dement Geriatr Cogn Disord 2017; 41:123-36. [PMID: 26891227 DOI: 10.1159/000442941] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/30/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND There is a proven link between Down syndrome and the early development of the neuropathological features of Alzheimer's disease (AD). Changes in the personality and behavior of adults with Down syndrome might indicate the early stages of dementia or of frontotemporal lobar degeneration. The objective of this study was to investigate the executive functions and changes in behavior associated with frontal lobe degeneration in individuals with Down syndrome who develop AD. We conducted a systematic review selecting studies employing cognitive assessments. SUMMARY We identified few studies using objective measurements to determine whether cognitive aspects associated with the frontal lobe correlate with dementia in this population. We observed a tendency toward such correlations. KEY MESSAGES There is a need for further studies in which objective measures of cognitive and behavioral factors are evaluated together with data related to brain function and morphology.
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30
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Karelina T, Demin O, Nicholas T, Lu Y, Duvvuri S, Barton HA. A Translational Systems Pharmacology Model for Aβ Kinetics in Mouse, Monkey, and Human. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2017; 6:666-675. [PMID: 28571112 PMCID: PMC5658289 DOI: 10.1002/psp4.12211] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 03/13/2017] [Accepted: 05/18/2017] [Indexed: 01/06/2023]
Abstract
A mechanistic model of amyloid beta production, degradation, and distribution was constructed for mouse, monkey, and human, calibrated and externally verified across multiple datasets. Simulations of single‐dose avagacestat treatment demonstrate that the Aβ42 brain inhibition may exceed that in cerebrospinal fluid (CSF). The dose that achieves 50% CSF Aβ40 inhibition for humans (both healthy and with Alzheimer's disease (AD)) is about 1 mpk, one order of magnitude lower than for mouse (10 mpk), mainly because of differences in pharmacokinetics. The predicted maximal percent of brain Aβ42 inhibition after single‐dose avagacestat is higher for AD subjects (about 60%) than for healthy individuals (about 45%). The probability of achieving a normal physiological level for Aβ42 in brain (1 nM) during multiple avagacestat dosing can be increased by using a dosing regimen that achieves higher exposure. The proposed model allows prediction of brain pharmacodynamics for different species given differing dosing regimens.
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Affiliation(s)
- T Karelina
- Institute for Systems Biology, Moscow, Russia
| | - O Demin
- Institute for Systems Biology, Moscow, Russia
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31
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Abstract
Down syndrome (Trisomy 21; DS) is a unique disease known to be associated with early-onset Alzheimer's disease (AD). The initial presentation of AD in DS is usually difficult to recognize, owing to the underlying intellectual disabilities. Using biomarkers as a prediction tool for detecting AD in at-risk people with DS may benefit patient care. The objective of this review is to discuss the utility of biomarkers in DS on the basis of the pathophysiology of the disease and to provide an update on recent studies in this field. Only through the comprehensive assessment of clinical symptoms, imaging studies, and biomarker analyses can people with DS who are at risk for AD be diagnosed early. Studies for biomarkers of AD in DS have focused on the common pathophysiology of AD in people with DS and in the general population. The most extensively studied biomarkers are amyloid and tau. Owing to the nature of amyloid precursor protein overproduction in DS, the baseline β-amyloid (Aβ) plasma levels are higher than those in controls. Hence, the changes in Aβ are considered to be a predictive marker for AD in DS. In addition, other markers related to telomere length, neuroinflammation, and methylation have been investigated for their correlation with AD progression. Future studies including different ethnic groups may be helpful to collect sufficient data to monitor drug safety and efficacy, stratify patients at risk for AD, and quantify the benefit of treatment.
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Affiliation(s)
- Ni-Chung Lee
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Yin-Hsiu Chien
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Wuh-Liang Hwu
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
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32
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Park L, Uekawa K, Garcia-Bonilla L, Koizumi K, Murphy M, Pistik R, Younkin L, Younkin S, Zhou P, Carlson G, Anrather J, Iadecola C. Brain Perivascular Macrophages Initiate the Neurovascular Dysfunction of Alzheimer Aβ Peptides. Circ Res 2017; 121:258-269. [PMID: 28515043 DOI: 10.1161/circresaha.117.311054] [Citation(s) in RCA: 152] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
RATIONALE Increasing evidence indicates that alterations of the cerebral microcirculation may play a role in Alzheimer disease, the leading cause of late-life dementia. The amyloid-β peptide (Aβ), a key pathogenic factor in Alzheimer disease, induces profound alterations in neurovascular regulation through the innate immunity receptor CD36 (cluster of differentiation 36), which, in turn, activates a Nox2-containing NADPH oxidase, leading to cerebrovascular oxidative stress. Brain perivascular macrophages (PVM) located in the perivascular space, a major site of brain Aβ collection and clearance, are juxtaposed to the wall of intracerebral resistance vessels and are a powerful source of reactive oxygen species. OBJECTIVE We tested the hypothesis that PVM are the main source of reactive oxygen species responsible for the cerebrovascular actions of Aβ and that CD36 and Nox2 in PVM are the molecular substrates of the effect. METHODS AND RESULTS Selective depletion of PVM using intracerebroventricular injection of clodronate abrogates the reactive oxygen species production and cerebrovascular dysfunction induced by Aβ applied directly to the cerebral cortex, administered intravascularly, or overproduced in the brain of transgenic mice expressing mutated forms of the amyloid precursor protein (Tg2576 mice). In addition, using bone marrow chimeras, we demonstrate that PVM are the cells expressing CD36 and Nox2 responsible for the dysfunction. Thus, deletion of CD36 or Nox2 from PVM abrogates the deleterious vascular effects of Aβ, whereas wild-type PVM reconstitute the vascular dysfunction in CD36-null mice. CONCLUSIONS The data identify PVM as a previously unrecognized effector of the damaging neurovascular actions of Aβ and unveil a new mechanism by which brain-resident innate immune cells and their receptors may contribute to the pathobiology of Alzheimer disease.
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Affiliation(s)
- Laibaik Park
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.).
| | - Ken Uekawa
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Lidia Garcia-Bonilla
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Kenzo Koizumi
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Michelle Murphy
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Rose Pistik
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Linda Younkin
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Steven Younkin
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Ping Zhou
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - George Carlson
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Josef Anrather
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.)
| | - Costantino Iadecola
- From the Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (L.P., K.U., L.G.B., K.K., M.M., P.Z., J.A., C.I.); McLaughlin Research Institute, Great Falls, MT (R.P., G.C.); and Mayo Clinic Jacksonville, FL (L.Y., S.Y.).
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33
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Kim MY, Kim KN, Cho HM, Lee DJ, Cho DY. Reference Intervals for Plasma Amyloid β in Korean Adults Without Cognitive Impairment. Ann Lab Med 2017; 36:595-8. [PMID: 27578514 PMCID: PMC5011114 DOI: 10.3343/alm.2016.36.6.595] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 06/13/2016] [Accepted: 07/18/2016] [Indexed: 11/19/2022] Open
Abstract
Amyloid β (Aβ) peptides are important components of plaques in patients with Alzheimer's disease (AD). Recent studies suggest that a low plasma ratio of Aβ42 to Aβ40 may precede the development of the sporadic form of AD. The aim of this study was to establish reference intervals for plasma Aβ in Korean adults. A total of 370 apparently healthy individuals (181 males and 189 females aged 40-69 yr) without cognitive impairment were enrolled. Plasma concentrations of Aβ40 and Aβ42 were measured by using a human amyloid β assay kit (Immuno-Biological Laboratories, Japan). Reference intervals were established according to the "CLSI guidelines for defining, establishing, and verifying reference intervals in the clinical laboratory". There was no need to partition the data with respect to gender or age group. The 95th percentile reference intervals for Aβ40 and Aβ42 were 127-331 pg/mL and 2.31-19.84 pg/mL, respectively. The reference interval for the Aβ42/Aβ40 ratio was 0.011-0.092. Plasma Aβ concentrations obtained in this study could be used as reference intervals for clinical purposes.
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Affiliation(s)
- Min Young Kim
- Department of Family Practice & Community Health, Ajou University School of Medicine, Suwon, Korea
| | - Kyu Nam Kim
- Department of Family Practice & Community Health, Ajou University School of Medicine, Suwon, Korea
| | - Hye Min Cho
- Department of Family Practice & Community Health, Ajou University School of Medicine, Suwon, Korea
| | - Duck Joo Lee
- Department of Family Practice & Community Health, Ajou University School of Medicine, Suwon, Korea
| | - Doo Yeoun Cho
- Department of Clinical Pharmacology and Therapeutics, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
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34
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Lee NC, Yang SY, Chieh JJ, Huang PT, Chang LM, Chiu YN, Huang AC, Chien YH, Hwu WL, Chiu MJ. Blood Beta-Amyloid and Tau in Down Syndrome: A Comparison with Alzheimer's Disease. Front Aging Neurosci 2017; 8:316. [PMID: 28144219 PMCID: PMC5239773 DOI: 10.3389/fnagi.2016.00316] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/08/2016] [Indexed: 11/13/2022] Open
Abstract
Background: Changes in β-amyloids (Aβ) and tau proteins have been noted in patients with Alzheimer's disease (AD) and patients with both Down syndrome (DS) and AD. However, reports of changes in the early stage of regression, such as behavioral and psychological symptoms of dementia (BPSD), in DS are sparse. Methods: Seventy-eight controls, 62 patients with AD, 35 with DS and 16 with DS with degeneration (DS_D), including 9 with BPSD and 7 with dementia, were enrolled. The levels of β-amyloids 40 and 42 (Aβ-40, Aβ-42) and tau protein in the blood were analyzed using immunomagnetic reduction (IMR). The Adaptive Behavior Dementia Questionnaire (ABDQ) was used to evaluate the clinical status of the degeneration. Results: The Aβ-40 and tau levels were higher and the Aβ-42 level and Aβ-42/Aβ-40 ratio were lower in DS than in the controls (all p < 0.001). Decreased Aβ-40 and increased Aβ-42 levels and Aβ-42/40 ratios were observed in DS_D compared with DS without degeneration (all p < 0.001). The ABDQ score was negatively correlated with the Aβ-40 level (ρ = -0.556) and the tau protein level (ρ = -0.410) and positively associated with the Aβ-42 level (ρ = 0.621) and the Aβ-42/40 ratio (ρ = 0.544; all p < 0.05). Conclusions: The Aβ-40 and Aβ-42 levels and the Aβ-42/Aβ-40 ratio are considered possible biomarkers for the early detection of degeneration in DS. The elevated Aβ-40 and tau levels in DS may indicate early neurodegeneration. The increased Aβ-42 in DS_D may reflect the neurotoxicity of Aβ-42. The paradox of the tau decreases in DS_D could be explained by a burnout phenomenon during long-term neurodegeneration. The different patterns of the plasma beta amyloids and tau protein may imply a different pathogenesis between DS with degeneration and AD in the general population, in spite of their common key pathological features.
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Affiliation(s)
- Ni-Chung Lee
- Department of Pediatrics, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan
| | | | - Jen-Jie Chieh
- Institute of Electro-Optical Science and Technology, National Taiwan Normal University Taipei, Taiwan
| | - Po-Tsang Huang
- Department of Clinical Psychology Center, National Taiwan University Hospital, College of Medicine, National Taiwan University Taipei, Taiwan
| | - Lih-Maan Chang
- Department of Clinical Psychology Center, National Taiwan University Hospital, College of Medicine, National Taiwan University Taipei, Taiwan
| | - Yen-Nan Chiu
- Department of Psychiatry, National Taiwan University Hospital, College of Medicine, National Taiwan University Taipei, Taiwan
| | - Ai-Chiu Huang
- Department of Medical Genetics, National Taiwan University Hospital, College of Medicine, National Taiwan University Taipei, Taiwan
| | - Yin-Hsiu Chien
- Department of Pediatrics, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan
| | - Wuh-Liang Hwu
- Department of Pediatrics, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan
| | - Ming-Jang Chiu
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan UniversityTaipei, Taiwan; Graduate Institute of Brain and Mind Sciences, College of Medicine, National Taiwan UniversityTaipei, Taiwan; Department of Psychology, National Taiwan UniversityTaipei, Taiwan; Graduate Institute of Biomedical Engineering and Bioinformatics, National Taiwan UniversityTaipei, Taiwan
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35
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Doran E, Keator D, Head E, Phelan MJ, Kim R, Totoiu M, Barrio JR, Small GW, Potkin SG, Lott IT. Down Syndrome, Partial Trisomy 21, and Absence of Alzheimer's Disease: The Role of APP. J Alzheimers Dis 2017; 56:459-470. [PMID: 27983553 PMCID: PMC5662115 DOI: 10.3233/jad-160836] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Overexpression of the amyloid precursor protein (APP) gene on chromosome 21 in Down syndrome (DS) has been linked to increased brain amyloid levels and early-onset Alzheimer's disease (AD). An elderly man with phenotypic DS and partial trisomy of chromosome 21 (PT21) lacked triplication of APP affording an opportunity to study the role of this gene in the pathogenesis of dementia. Multidisciplinary studies between ages 66-72 years comprised neuropsychological testing, independent neurological exams, amyloid PET imaging with 11C-Pittsburgh compound-B (PiB), plasma amyloid-β (Aβ) measurements, and a brain autopsy examination. The clinical phenotype was typical for DS and his intellectual disability was mild in severity. His serial neuropsychological test scores showed less than a 3% decline as compared to high functioning individuals with DS who developed dementia wherein the scores declined 17-28% per year. No dementia was detected on neurological examinations. On PiB-PET scans, the patient with PT21 had lower PiB standard uptake values than controls with typical DS or sporadic AD. Plasma Aβ42 was lower than values for demented or non-demented adults with DS. Neuropathological findings showed only a single neuritic plaque and neurofibrillary degeneration consistent with normal aging but not AD. Taken together the findings in this rare patient with PT21 confirm the obligatory role of APP in the clinical, biochemical, and neuropathological findings of AD in DS.
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Affiliation(s)
- Eric Doran
- Department of Pediatrics, University of California, Irvine, Orange, CA, USA
| | - David Keator
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA, USA
| | - Elizabeth Head
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Michael J. Phelan
- Department of Statistics, University of California, Irvine, Irvine, CA, USA
| | - Ron Kim
- Department of Pathology, University of California, Irvine, Orange, CA, USA
| | - Minodora Totoiu
- Department of Pediatrics, University of California, Irvine, Orange, CA, USA
| | - Jorge R. Barrio
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Gary W. Small
- Department of Psychiatry and Biobehavioral Sciences and the Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
| | - Steven G. Potkin
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA, USA
| | - Ira T. Lott
- Department of Pediatrics, University of California, Irvine, Orange, CA, USA,Corresponding author: Ira T. Lott, MD, Address: University of California, Irvine Medical Center, 101 The City Drive South, ZC 4482, Orange, CA 92868, Phone: 714-456-5333, Fax: 714-456-8466,
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36
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Plasma Amyloid Beta 1-42 and DNA Methylation Pattern Predict Accelerated Aging in Young Subjects with Down Syndrome. Neuromolecular Med 2016; 18:593-601. [DOI: 10.1007/s12017-016-8413-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/14/2016] [Indexed: 01/17/2023]
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37
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Head E, Lott IT, Wilcock DM, Lemere CA. Aging in Down Syndrome and the Development of Alzheimer's Disease Neuropathology. Curr Alzheimer Res 2016; 13:18-29. [PMID: 26651341 PMCID: PMC4948181 DOI: 10.2174/1567205012666151020114607] [Citation(s) in RCA: 156] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/18/2015] [Accepted: 09/01/2015] [Indexed: 02/04/2023]
Abstract
Chromosome 21, triplicated in Down Syndrome, contains several genes that are thought to play a critical role in the development of AD neuropathology. The overexpression of the gene for the amyloid precursor protein (APP), on chromosome 21, leads to early onset beta-amyloid (Aβ) plaques in DS. In addition to Aβ accumulation, middle-aged people with DS develop neurofibrillary tangles, cerebrovascular pathology, white matter pathology, oxidative damage, neuroinflammation and neuron loss. There is also evidence of potential compensatory responses in DS that benefit the brain and delay the onset of dementia after there is sufficient neuropathology for a diagnosis of AD. This review describes some of the existing literature and also highlights gaps in our knowledge regarding AD neuropathology in DS. It will be critical in the future to develop networked brain banks with standardized collection procedures to fully characterize the regional and temporal pathological events associated with aging in DS. As more information is acquired regarding AD evolution in DS, there will be opportunities to develop interventions that are age-appropriate to delay AD in DS.
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Affiliation(s)
- Elizabeth Head
- Sanders Brown Center on Aging, University of Kentucky, 800 South Limestone Street, Lexington, KY, 40536, USA.
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38
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Hoyo LD, Xicota L, Sánchez-Benavides G, Cuenca-Royo A, de Sola S, Langohr K, Fagundo AB, Farré M, Dierssen M, de la Torre R. Semantic Verbal Fluency Pattern, Dementia Rating Scores and Adaptive Behavior Correlate With Plasma Aβ42 Concentrations in Down Syndrome Young Adults. Front Behav Neurosci 2015; 9:301. [PMID: 26635555 PMCID: PMC4649024 DOI: 10.3389/fnbeh.2015.00301] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 10/28/2015] [Indexed: 12/19/2022] Open
Abstract
Down syndrome (DS) is an intellectual disability (ID) disorder in which language and specifically, verbal fluency are strongly impaired domains; nearly all adults show neuropathology of Alzheimer’s disease (AD), including amyloid deposition by their fifth decade of life. In the general population, verbal fluency deficits are considered a strong AD predictor being the semantic verbal fluency task (SVFT) a useful tool for enhancing early diagnostic. However, there is a lack of information about the association between the semantic verbal fluency pattern (SVFP) and the biological amyloidosis markers in DS. In the current study, we used the SVFT in young adults with DS to characterize their SVFP, assessing total generated words, clustering, and switching. We then explored its association with early indicators of dementia, adaptive behavior and amyloidosis biomarkers, using the Dementia Questionnaire for Persons with Intellectual Disability (DMR), the Adaptive Behavior Assessment System-Second Edition (ABAS-II), and plasma levels of Aβ peptides (Aβ40 and Aβ42), as a potent biomarker of AD. In DS, worse performance in SVFT and poorer communication skills were associated with higher plasma Aβ42 concentrations, a higher DMR score and impaired communication skills (ABAS–II). The total word production and switching ability in SVFT were good indicators of plasma Aβ42 concentration. In conclusion, we propose the SVFT as a good screening test for early detection of dementia and amyloidosis in young adults with DS.
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Affiliation(s)
- Laura Del Hoyo
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain ; Departamento de farmacología, Universitat Autònoma de Barcelona Barcelona, Spain
| | - Laura Xicota
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain ; Systems Biology Program, Cellular and Systems Neurobiology, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology Barcelona, Spain ; Department of Experimental and Health Sciences, Universitat Pompeu Fabra Barcelona, Spain
| | - Gonzalo Sánchez-Benavides
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain
| | - Aida Cuenca-Royo
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain
| | - Susana de Sola
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain ; Systems Biology Program, Cellular and Systems Neurobiology, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology Barcelona, Spain
| | - Klaus Langohr
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain ; Department of Statistics and Operations Research, Universitat Politècnica de Barcelona/BarcelonaTech Barcelona, Spain
| | - Ana B Fagundo
- Department of Psychiatry, University Hospital of Bellvitge-IDIBELL Barcelona, Spain ; CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III Madrid, Spain
| | - Magí Farré
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain ; Departamento de farmacología, Universitat Autònoma de Barcelona Barcelona, Spain
| | - Mara Dierssen
- Systems Biology Program, Cellular and Systems Neurobiology, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology Barcelona, Spain ; Department of Experimental and Health Sciences, Universitat Pompeu Fabra Barcelona, Spain ; CIBER de Enfermedades Raras (CIBERER), Instituto Salud Carlos III Madrid, Spain
| | - Rafael de la Torre
- Neurosciences Research Program, Integrative Pharmacology and Systems Neuroscience Research Group, IMIM-Institut de Hospital del Mar d'Investigacions Mèdiques Barcelona, Spain ; Department of Experimental and Health Sciences, Universitat Pompeu Fabra Barcelona, Spain ; CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III Madrid, Spain
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39
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Llado-Saz S, Atienza M, Cantero JL. Increased levels of plasma amyloid-beta are related to cortical thinning and cognitive decline in cognitively normal elderly subjects. Neurobiol Aging 2015; 36:2791-7. [PMID: 26182906 DOI: 10.1016/j.neurobiolaging.2015.06.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 06/14/2015] [Accepted: 06/17/2015] [Indexed: 12/30/2022]
Abstract
Plasma levels of circulating amyloid-beta (Aβ) peptides are of particular interest in Alzheimer' disease, but little is known about cognitive and cortical correlates of peripheral Aβ levels in normal aging. Here, we compared cognitive functioning, vascular risk factors, and patterns of cortical thickness between cognitively intact elderly subjects with low (N = 60) and high (N = 60) plasma Aβ levels (cutoffs: 225 pg/mL and 23 pg/mL for Aβ1-40 and Aβ1-42, respectively). Overall, subjects with high Aβ levels showed lower cognitive performance and thinner cortex than those with low Aβ levels. More specifically, subjects with high Aβ1-40 showed bilateral thinning of the prefrontal cortex, poorer objective memory, slower processing speed, and lower nonverbal reasoning skills, whereas subjects with high Aβ1-42 had thinner temporal lobe, poorer everyday memory, and increased levels of homocysteine. Overall, these results suggest that high plasma Aβ levels in normal elderly subjects are associated with subclinical markers of vulnerable aging, which may be helpful at predicting different trajectories of aging in cognitively intact older adults.
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Affiliation(s)
- Sandra Llado-Saz
- Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain
| | - Mercedes Atienza
- Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain
| | - Jose L Cantero
- Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain.
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40
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Schupf N, Lee A, Park N, Dang LH, Pang D, Yale A, Oh DKT, Krinsky-McHale SJ, Jenkins EC, Luchsinger JA, Zigman WB, Silverman W, Tycko B, Kisselev S, Clark L, Lee JH. Candidate genes for Alzheimer's disease are associated with individual differences in plasma levels of beta amyloid peptides in adults with Down syndrome. Neurobiol Aging 2015; 36:2907.e1-10. [PMID: 26166206 DOI: 10.1016/j.neurobiolaging.2015.06.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 06/08/2015] [Accepted: 06/14/2015] [Indexed: 01/08/2023]
Abstract
We examined the contribution of candidates genes for Alzheimer's disease (AD) to individual differences in levels of beta amyloid peptides in adults with Down syndrom, a population at high risk for AD. Participants were 254 non-demented adults with Down syndrome, 30-78 years of age. Genomic deoxyribonucleic acid was genotyped using an Illumina GoldenGate custom array. We used linear regression to examine differences in levels of Aβ peptides associated with the number of risk alleles, adjusting for age, sex, level of intellectual disability, race and/or ethnicity, and the presence of the APOE ε4 allele. For Aβ42 levels, the strongest gene-wise association was found for a single nucleotide polymorphism (SNP) on CAHLM1; for Aβ40 levels, the strongest gene-wise associations were found for SNPs in IDE and SOD1, while the strongest gene-wise associations with levels of the Aβ42/Aβ40 ratio were found for SNPs in SORCS1. Broadly classified, variants in these genes may influence amyloid precursor protein processing (CALHM1, IDE), vesicular trafficking (SORCS1), and response to oxidative stress (SOD1).
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Affiliation(s)
- Nicole Schupf
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA; G.H. Sergievsky Center, New York, NY, USA; Department of Epidemiology, Columbia University Medical Center, New York, NY, USA; Department of Psychiatry, Columbia University Medical Center, New York, NY, USA.
| | - Annie Lee
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Naeun Park
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Lam-Ha Dang
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Deborah Pang
- Department of Psychology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Alexander Yale
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| | - David Kyung-Taek Oh
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| | - Sharon J Krinsky-McHale
- Department of Psychology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Edmund C Jenkins
- Department of Human Genetics, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - José A Luchsinger
- Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Warren B Zigman
- Department of Psychology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Wayne Silverman
- Kennedy Krieger Institute and Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Benjamin Tycko
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| | - Sergey Kisselev
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Lorraine Clark
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Joseph H Lee
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA; G.H. Sergievsky Center, New York, NY, USA; Department of Epidemiology, Columbia University Medical Center, New York, NY, USA
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de Winter CF, Echteld MA, Evenhuis HM. Chronic kidney disease in older people with intellectual disability: results of the HA-ID study. RESEARCH IN DEVELOPMENTAL DISABILITIES 2014; 35:726-732. [PMID: 24287320 DOI: 10.1016/j.ridd.2013.11.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 06/02/2023]
Abstract
With increasing longevity and cardiovascular events, chronic kidney disease may also become a significant problem in older people with intellectual disability (ID). We studied prevalence and associations of chronic kidney disease as part of the Healthy Ageing and Intellectual Disability (HA-ID) study, a large Dutch cross-sectional study among people with ID aged 50 years and over, using creatinine and cystatin-C measurement in plasma. Glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. Equations based on creatinine (as the MDRD equation) may underestimate kidney dysfunction in people with sarcopenia, because low muscle mass leads to a low creatinine production. Therefore, also prevalence of chronic kidney disease was studied in the sarcopenic group, using different GFR equations. Prevalence of chronic kidney disease, among 635 participants, was 15.3%, which equals prevalence in the general Dutch population. In the group of participants with sarcopenia (n=82), the CKD-EPI equation based on creatinine and cystatin-C gave a higher prevalence of chronic kidney disease than did the MDRD equation, but confidence intervals were very wide. Chronic kidney disease was associated with higher age, Down syndrome, obesity, hypercholesterolemia and hypothyroid disease. GFR should be measured in all older people with ID and polypharmacy, and in older people with ID and Down syndrome as part of the regular health checks. Moreover, if sarcopenia is present and information on GFR is required, this should not be measured based on creatinine only, but additional measures, such as cystatin-C, should be taken into account.
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Affiliation(s)
- C F de Winter
- Intellectual Disability Medicine, Erasmus Medical Center Rotterdam, Department of General Practice, Rotterdam, The Netherlands; Reinaerde, Den Dolder, The Netherlands.
| | - M A Echteld
- Intellectual Disability Medicine, Erasmus Medical Center Rotterdam, Department of General Practice, Rotterdam, The Netherlands
| | - H M Evenhuis
- Intellectual Disability Medicine, Erasmus Medical Center Rotterdam, Department of General Practice, Rotterdam, The Netherlands
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Rohn TT, McCarty KL, Love JE, Head E. Is Apolipoprotein E4 an Important Risk Factor for Dementia in Persons with Down Syndrome? ACTA ACUST UNITED AC 2014; 1. [PMID: 25594074 DOI: 10.13188/2376-922x.1000004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Down syndrome is one of the most common genetic causes of intellectual disability and is characterized by a number of behavioral as well as cognitive symptoms. Triplication of all or part of human chromosome 21 has been considered as the main cause of Down syndrome. Due to the location of the amyloid precursor protein on chromosome 21, many of the neuropathological features of early-onset Alzheimer's disease including senile plaques and neurofibrillary tangles are also present in Down syndrome patients who are either demented or nondemented. Significant advances in medical treatment have increased longevity in people with Down syndrome resulting in an increased population that may be subjected to many of the same risk factors as those with Alzheimer's disease. It is well established that harboring one or both apolipoprotein E4 alleles greatly increases the risk for Alzheimer's disease. However, whether apolipoprotein E4 contributes to an earlier onset of dementia or increased mortality in Down syndrome patients is still a matter of debate. The purpose of this mini review is to provide an updated assessment on apolipoprotein E4 status and risk potential of developing dementia and mortality associated with Down syndrome.
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Affiliation(s)
- Troy T Rohn
- Department of Biological Sciences, Science Building, Boise State University, USA
| | - Katie L McCarty
- University of Kentucky, Department of Pharmacology & Nutritional Sciences, Sanders-Brown Center on Aging, Lexington, KY
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Bianchi P, Bettini S, Guidi S, Ciani E, Trazzi S, Stagni F, Ragazzi E, Franceschini V, Bartesaghi R. Age-related impairment of olfactory bulb neurogenesis in the Ts65Dn mouse model of Down syndrome. Exp Neurol 2013; 251:1-11. [PMID: 24192151 DOI: 10.1016/j.expneurol.2013.10.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 10/11/2013] [Accepted: 10/15/2013] [Indexed: 10/26/2022]
Abstract
Down syndrome (DS) is a genetic condition caused by triplication of chromosome 21. Widespread neurogenesis reduction during brain development underlies the numerous neurological defects of DS. These defects start to manifest themselves at birth and worsen with age. However, unlike other brain functions, smell is impaired only at advanced life stages, suggesting preservation of olfactory bulb neurogenesis up to adulthood. To clarify this issue, in the current study we examined olfactory bulb (OB) neurogenesis and olfactory function by exploiting the Ts65Dn mouse, a widely used model of DS. We found that in young (15-day-old) Ts65Dn mice, in spite of a reduced proliferation rate in the subventricular zone (SVZ) in comparison with euploid mice, the number of neuroblasts traveling in the rostral migratory stream (RMS), en route to the OB, and the number of new granule neurons added to the OB were similar to those of euploid mice. In mid-age (13-month-old) Ts65Dn mice, however, the proliferation rate in the SVZ was more severely reduced in comparison with euploid mice and the number of neuroblasts in the RMS and new granule neurons added to the OB underwent a reduction. While in young Ts65Dn mice the olfactory function, assessed with the buried food pellet test, was similar to that of euploid mice, in mid-age mice it was significantly impaired. Taken together, results suggest that an age-related reduction in the renewal of OB granule cells may underlie the age-related smell impairment in DS.
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Affiliation(s)
- Patrizia Bianchi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Simone Bettini
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Sandra Guidi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Fiorenza Stagni
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Elena Ragazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Valeria Franceschini
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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Impairment of proteostasis network in Down syndrome prior to the development of Alzheimer's disease neuropathology: redox proteomics analysis of human brain. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1249-59. [PMID: 23603808 DOI: 10.1016/j.bbadis.2013.04.013] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 03/18/2013] [Accepted: 04/10/2013] [Indexed: 01/06/2023]
Abstract
DS is the most frequent genetic cause of intellectual disability characterized by the anomalous presence of three copies of chromosome 21. One of the peculiar features of DS is the onset of Alzheimer's disease neuropathology after the age of 40years characterized by deposition of senile plaques and neurofibrillary tangles. Growing studies demonstrated that increased oxidative damage, accumulation of unfolded/damaged protein aggregates and dysfunction of intracellular degradative system are key players in neurodegenerative processes. In this study, redox proteomics approach was used to analyze the frontal cortex from DS subjects under the age of 40 compared with age-matched controls, and proteins found to be increasingly carbonylated were identified. Interestingly, our results showed that oxidative damage targets specifically different components of the intracellular quality control system such as GRP78, UCH-L1, V0-ATPase, cathepsin D and GFAP that couples with decreased activity of the proteasome and autophagosome formation observed. We also reported a slight but consistent increase of Aβ 1-42 SDS- and PBS-soluble form and tau phosphorylation in DS versus CTR. We suggest that disturbance in the proteostasis network could contribute to the accumulation of protein aggregates, such as amyloid deposits and NFTs, which occur very early in DS. It is likely that a sub-optimal functioning of degradative systems occur in DS neurons, which in turn provide the basis for further accumulation of toxic protein aggregates. The results of this study suggest that oxidation of protein members of the proteostatis network is an early event in DS and might contribute to neurodegenerative phenomena.
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Toledo JB, Shaw LM, Trojanowski JQ. Plasma amyloid beta measurements - a desired but elusive Alzheimer's disease biomarker. ALZHEIMERS RESEARCH & THERAPY 2013; 5:8. [PMID: 23470128 PMCID: PMC3706955 DOI: 10.1186/alzrt162] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cerebrospinal fluid and positron emission tomography biomarkers accurately predict an underlying Alzheimer's disease (AD) pathology; however, they represent either invasive or expensive diagnostic tools. Therefore, a blood-based biomarker like plasma amyloid beta (Aβ) that could correlate with the underlying AD pathology and serve as a prognostic biomarker or an AD screening strategy is urgently needed as a cost-effective and non-invasive diagnostic tool. In this paper we review the demographic, biologic, genetic and technical aspects that affect plasma Aβ levels. Findings of cross-sectional and longitudinal studies of plasma Aβ, including autosomal dominant AD cases, sporadic AD cases, Down syndrome cases and population studies, are also discussed. Finally, we review the association between cerebrovascular disease and Aβ plasma levels and the responses observed in clinical trials. Based on our review of the current literature on plasma Aβ, we conclude that further clinical research and assay development are needed before measures of plasma Aβ can be interpreted so they can be applied as trait, risk or state biomarkers for AD.
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Affiliation(s)
- Jon B Toledo
- Department of Pathology and Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Leslie M Shaw
- Department of Pathology and Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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McCabe LL, McCabe ERB. Down syndrome and personalized medicine: changing paradigms from genotype to phenotype to treatment. Congenit Anom (Kyoto) 2013; 53:1-2. [PMID: 23480351 DOI: 10.1111/cga.12000] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 09/06/2012] [Indexed: 11/29/2022]
Abstract
Personalized Medicine represents a paradigm shift in the conceptual framework of research and clinical care. This shift argues that Down syndrome is a treatable condition, and therefore we must invest in research to improve outcomes. Individuals with Down syndrome have varying levels of increased risk for a number of co-morbidities, including infantile spasms and early onset Alzheimer's disease. We will review research in these associated conditions to show how investigators are attempting to identify biomarkers, including genomic, epigenomic, proteomic and metabolomic "signatures" that will predict who may be at risk to develop a specific co-morbidity prior to onset and will provide novel targets for therapeutic development. This Personalized Medicine approach will permit predictive and preventive approaches for individuals at increased risk for co-morbidities. The support for clinical trials among individuals with Down syndrome is beginning to overcome the "culture of intractability" that has surrounded this disorder.
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Affiliation(s)
- Linda L McCabe
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO, USA
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Head E, Powell D, Gold BT, Schmitt FA. Alzheimer's Disease in Down Syndrome. EUROPEAN JOURNAL OF NEURODEGENERATIVE DISEASE 2012; 1:353-364. [PMID: 25285303 PMCID: PMC4184282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A key challenge to adults with Down syndrome (DS) as they age is an increased risk for cognitive decline, dementia, and Alzheimer disease (AD). In DS persons ranging from 40-49 years of age, 5.7-55% may be clinically demented and between 50-59 years, dementia prevalence ranges from 4-55% (reviewed in [1]). Despite the wide ranges reported for dementia prevalence, a consistent feature of aging in DS is the progressive accumulation of AD brain pathologies. By the age of 40 years, virtually all have sufficient senile plaques and neurofibrillary tangles for a neuropathological diagnosis of AD [2]. Thus, there is dissociation between the age of onset of AD neuropathology (40 years) and increasing signs of clinical dementia. We discuss the hypothesis that frontal impairments are a critical factor affecting cognitive function and are associated with white matter (WM) and AD neuropathology. While these may be an early sign of conversion to dementia, we also review several other clinical comorbidities that may also contribute to dementia onset.
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Affiliation(s)
- Elizabeth Head
- Department of Molecular and Biomedical Pharmacology, University of Kentucky Lexington, KY, 40356
- Sanders-Brown Center on Aging, University of Kentucky Lexington, KY, 40356
| | - David Powell
- Magnetic Resonance Imaging and Spectroscopy Center, University of Kentucky Lexington, KY, 40356
- Sanders-Brown Center on Aging, University of Kentucky Lexington, KY, 40356
| | - Brian T. Gold
- Department of Anatomy and Neurobiology, University of Kentucky Lexington, KY, 40356
- Sanders-Brown Center on Aging, University of Kentucky Lexington, KY, 40356
| | - Frederick A. Schmitt
- Department of Neurology, University of Kentucky Lexington, KY, 40356
- Sanders-Brown Center on Aging, University of Kentucky Lexington, KY, 40356
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Park L, Zhou P, Koizumi K, El Jamal S, Previti ML, Van Nostrand WE, Carlson G, Iadecola C. Brain and circulating levels of Aβ1-40 differentially contribute to vasomotor dysfunction in the mouse brain. Stroke 2012. [PMID: 23204056 DOI: 10.1161/strokeaha.112.670976] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND AND PURPOSE Amyloid-β (Aβ), a peptide that accumulates in the brain and circulates in the blood of patients with Alzheimer disease, alters the regulation of cerebral blood flow and may contribute to the brain dysfunction underlying the dementia. However, the contributions of brain and circulating Aβ1-40 to the vascular dysfunction have not been elucidated. METHODS We used transgenic mice overexpressing mutated forms of the amyloid precursor protein in which Aβ1-40 is elevated in blood and brain (Tg-2576) or only in brain (Tg-SwDI). Mice were equipped with a cranial window, and the increase in cerebral blood flow induced by neural activity (whisker stimulation), or by topical application of endothelium-dependent vasodilators, was assessed by laser-Doppler flowmetry. RESULTS The cerebrovascular dysfunction was observed also in Tg-SwDI mice, but despite ≈40% higher levels of brain Aβ1-40, the effect was less marked than in Tg-2576 mice. Intravascular administration of Aβ1-40 elevated plasma Aβ1-40 and enhanced the dysfunction in Tg-SwDI mice, but not in Tg-2576 mice. CONCLUSIONS The results provide evidence that Aβ1-40 acts on distinct luminal and abluminal vascular targets, the deleterious cerebrovascular effects of which are additive. Furthermore, the findings highlight the importance of circulating Aβ1-40 in the cerebrovascular dysfunction and may provide insight into the cerebrovascular alterations in conditions in which elevations in plasma Aβ1-40 occur.
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Affiliation(s)
- Laibaik Park
- Brain and Mind Research Institute, Weill Medical College of Cornell University, 411 E 69th St, KB410, New York, NY 10021, USA
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Abstract
PURPOSE OF REVIEW Improvements in health and social care for people with intellectual disability have led to a dramatic increase in the life expectancy of this population, resulting in a large and growing number of older adults with intellectual disability. They are at risk of age-related mental disorders such as dementia and continue to present with high rates of mental illness. RECENT FINDINGS Recent research with older adults with intellectual disability has included physical health issues that may affect mental well being, and biological and clinical features of dementia in people with Down syndrome. Two key clinical trials of memantine and antioxidants for dementia in Down syndrome showed that these treatment options were ineffective in the short term. Other research focussed on environmental and psychosocial issues (including carer issues) and end-of-life care. SUMMARY Improved mental well being requires effective management of mental illness and co-morbid physical health problems as well as consideration of environmental and social issues. Biological research has identified potential treatments for age-related decline, which has led to the development of medication trials. Despite disappointing results, two recent medication trials showed that randomized controlled trials are feasible in older people with intellectual disabilities - a group who are often excluded from trials.
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50
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Rissman RA, Trojanowski JQ, Shaw LM, Aisen PS. Longitudinal plasma amyloid beta as a biomarker of Alzheimer's disease. J Neural Transm (Vienna) 2012; 119:843-50. [PMID: 22354745 PMCID: PMC4305447 DOI: 10.1007/s00702-012-0772-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 01/31/2012] [Indexed: 01/07/2023]
Abstract
Alzheimer's disease (AD) affects more than twenty-five million people worldwide and is the most common form of dementia. Symptomatic treatments have been developed, but effective intervention to alter disease progression is needed. Targets have been identified for disease-modifying drugs, but the results of clinical trials have been disappointing. Peripheral biomarkers of disease state may improve clinical trial design and analysis, increasing the likelihood of successful drug development. Amyloid-related measures, presumably reflecting principal pathology of AD, are among the leading cerebrospinal fluid and neuroimaging biomarkers, and measurement of plasma levels of amyloid peptides has been the focus of much investigation. In this review, we discuss recent data on plasma β-amyloid (Aβ) and examine the issues that have arisen in establishing it as a reliable biomarker of AD.
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Affiliation(s)
- Robert A Rissman
- Alzheimer's Disease Cooperative Study, Department of Neurosciences, UCSD School of Medicine, La Jolla, CA 92037-0624, USA.
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