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Hansra GK, Jayasena T, Hosoki S, Poljak A, Lam BCP, Rust R, Sagare A, Zlokovic B, Thalamuthu A, Sachdev PS. Fluid biomarkers of the neurovascular unit in cerebrovascular disease and vascular cognitive disorders: A systematic review and meta-analysis. CEREBRAL CIRCULATION - COGNITION AND BEHAVIOR 2024; 6:100216. [PMID: 38510579 PMCID: PMC10951911 DOI: 10.1016/j.cccb.2024.100216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 01/30/2024] [Accepted: 02/16/2024] [Indexed: 03/22/2024]
Abstract
Background The disruption of the neurovascular unit (NVU), which maintains the integrity of the blood brain barrier (BBB), has been identified as a critical mechanism in the development of cerebrovascular and neurodegenerative disorders. However, the understanding of the pathophysiological mechanisms linking NVU dysfunction to the disorders is incomplete, and reliable blood biomarkers to measure NVU dysfunction are yet to be established. This systematic review and meta-analysis aimed to identify biomarkers associated with BBB dysfunction in large vessel disease, small vessel disease (SVD) and vascular cognitive disorders (VCD). Methods A literature search was conducted in PubMed, EMBASE, Scopus and PsychINFO to identify blood biomarkers related to dysfunction of the NVU in disorders with vascular pathologies published until 20 November 2023. Studies that assayed one or more specific markers in human serum or plasma were included. Quality of studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. Effects were pooled and methodological heterogeneity examined using the random effects model. Results A total of 112 studies were included in this review. Where study numbers allowed, biomarkers were analysed using random effect meta-analysis for VCD (1 biomarker; 5 studies) and cerebrovascular disorders, including stroke and SVD (9 biomarkers; 29 studies) while all remaining biomarkers (n = 17 biomarkers; 78 studies) were examined through qualitative analysis. Results of the meta-analysis revealed that cerebrospinal fluid/serum albumin quotient (Q-Alb) reliably differentiates VCD patients from healthy controls (MD = 2.77; 95 % CI = 1.97-3.57; p < 0.0001) while commonly measured biomarkers of endothelial dysfunction (VEGF, VCAM-1, ICAM-1, vWF and E-selectin) and neuronal injury (NfL) were significantly elevated in vascular pathologies. A qualitative assessment of non-meta-analysed biomarkers revealed NSE, NfL, vWF, ICAM-1, VCAM-1, lipocalin-2, MMP-2 and MMP-9 levels to be upregulated in VCD, although these findings were not consistently replicated. Conclusions This review identifies several promising biomarkers of NVU dysfunction which require further validation. A panel of biomarkers representing multiple pathophysiological pathways may offer greater discriminative power in distinguishing possible disease mechanisms of VCD.
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Affiliation(s)
- Gurpreet Kaur Hansra
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - Tharusha Jayasena
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - Satoshi Hosoki
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
- Department of Neurology, National Cerebral and Cardiovascular Centre, Suita, Japan
| | - Anne Poljak
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, University of New South Wales, NSW, Australia
| | - Ben Chun Pan Lam
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
- School of Psychology and Public Health, La Trobe University, Melbourne, Australia
| | - Ruslan Rust
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Abhay Sagare
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Berislav Zlokovic
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Anbupalam Thalamuthu
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - Perminder S. Sachdev
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, University of New South Wales, Sydney, Australia
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Hosoki S, Hansra GK, Jayasena T, Poljak A, Mather KA, Catts VS, Rust R, Sagare A, Kovacic JC, Brodtmann A, Wallin A, Zlokovic BV, Ihara M, Sachdev PS. Molecular biomarkers for vascular cognitive impairment and dementia. Nat Rev Neurol 2023; 19:737-753. [PMID: 37957261 DOI: 10.1038/s41582-023-00884-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2023] [Indexed: 11/15/2023]
Abstract
As disease-specific interventions for dementia are being developed, the ability to identify the underlying pathology and dementia subtypes is increasingly important. Vascular cognitive impairment and dementia (VCID) is the second most common cause of dementia after Alzheimer disease, but progress in identifying molecular biomarkers for accurate diagnosis of VCID has been relatively limited. In this Review, we examine the roles of large and small vessel disease in VCID, considering the underlying pathophysiological processes that lead to vascular brain injury, including atherosclerosis, arteriolosclerosis, ischaemic injury, haemorrhage, hypoperfusion, endothelial dysfunction, blood-brain barrier breakdown, inflammation, oxidative stress, hypoxia, and neuronal and glial degeneration. We consider the key molecules in these processes, including proteins and peptides, metabolites, lipids and circulating RNA, and consider their potential as molecular biomarkers alone and in combination. We also discuss the challenges in translating the promise of these biomarkers into clinical application.
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Affiliation(s)
- Satoshi Hosoki
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
- Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Gurpreet K Hansra
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Tharusha Jayasena
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Anne Poljak
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW, Australia
| | - Karen A Mather
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Vibeke S Catts
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Ruslan Rust
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Abhay Sagare
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Jason C Kovacic
- Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York, New York, NY, USA
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
- St Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Amy Brodtmann
- Department of Neurology, Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Anders Wallin
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Berislav V Zlokovic
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Masafumi Ihara
- Department of Neurology, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Perminder S Sachdev
- Centre for Healthy Brain Ageing, Discipline of Psychiatry and Mental Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia.
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Wang Q, Zhao J, Chang H, Liu X, Zhu R. Homocysteine and Folic Acid: Risk Factors for Alzheimer's Disease-An Updated Meta-Analysis. Front Aging Neurosci 2021; 13:665114. [PMID: 34122042 PMCID: PMC8188894 DOI: 10.3389/fnagi.2021.665114] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 04/09/2021] [Indexed: 01/11/2023] Open
Abstract
Background: Recent studies have reported that homocysteine (Hcy) may play a vital role in the pathogenesis of vascular dementia (VaD) and Alzheimer's disease (AD). Our study explored the relationship between the plasma Hcy and folate levels and the risk of dementia. Methods: We searched Embase, PubMed, and Web of Science for published literature, including case-control studies and prospective cohort studies, and performed a systematic analysis. Results: The results of our meta-analysis, consisting of case-control studies, showed higher levels of Hcy and lower levels of folate in dementia, AD, and VaD patients than those in non-demented controls (for dementia: SMD = 0.812, 95% CI [0.689, 0.936], p = 0.000 for Hcy; SMD = −0.677, 95% CI [−0.828, −0.525], p = 0.000 for folate). AD patients showed significantly lower plasma Hcy levels compared to VaD patients (SMD = −0.278, 95% CI [−0.466, −0.09], p = 0.000). Subgroup analysis revealed that ethnicity, average age, and dementia type had no significant effect on this association. Furthermore, from the analysis of prospective cohort studies, we identified that elevated plasma Hcy levels were associated with an increased risk of dementia, AD, and VaD (RRdementia = 1.22, 95% CI [1.08, 1.36]; RRAD = 1.07, 95% CI [1.04, 1.11]; RRVaD = 1.13, 95% CI [1.04, 1.23]). In addition, every 5 μmol/L increase in the plasma Hcy level was associated with a 9% increased risk of dementia and a 12% increased risk of AD. Conclusion: Hcy and folic acid are potential predictors of the occurrence and development of AD. A better understanding of their function in dementia could provide evidence for clinicians to rationalize clinical intervention strategies.
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Affiliation(s)
- Qianwen Wang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Jingjing Zhao
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Hongtao Chang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Xu Liu
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Ruixia Zhu
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
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Anuradha U, Kumar A, Singh RK. The clinical correlation of proinflammatory and anti-inflammatory biomarkers with Alzheimer disease: a meta-analysis. Neurol Sci 2021; 43:285-298. [PMID: 34032945 DOI: 10.1007/s10072-021-05343-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/19/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Numerous studies have indicated the role of inflammation in the pathogenesis of Alzheimer's disease (AD). However, the exact role of inflammatory markers in AD is still unclear. OBJECTIVE The main objective of the current study was to find out the association between the level of inflammatory markers and AD. MATERIAL AND METHODS The relevant articles have been extracted from PubMed as per the inclusion and exclusion criteria of the study. The mean value with standard deviation and number of participants in AD and control groups were extracted from relevant articles. The inverse variance was used as a statistical method and standard mean difference (SMD) as effect measure with 95% C.I. The random effect model was used and all analyses were done using Rev. Man 5.0. RESULTS A total of 38 articles have been found relevant and selected for analysis. The overall estimate results have shown that the level of IL-6, TGF-β1, and IL-1α were increased significantly in AD patients as compared to the control group among all other pro-inflammatory, inflammatory and anti-inflammatory mediators. CONCLUSION The findings of the current study suggest that IL-6, TGF-β1, and IL-1α may be a useful early marker in AD. However, further studies are required to confirm the exact utility of these inflammatory markers.
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Affiliation(s)
- Urati Anuradha
- Department of Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, (U.P), Lucknow, 226002, India
| | - Anoop Kumar
- Department of Pharmacology, Delhi Pharmaceutical Sciences & Research University (DPSRU), New Delhi, 110017, India
| | - Rakesh Kumar Singh
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, (U.P), Bijnor-Sisendi Road, Sarojini Nagar, Near CRPF Base Camp, Lucknow, UP, 226002, India.
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Gong C, Wei D, Wang Y, Ma J, Yuan C, Zhang W, Yu G, Zhao Y. A Meta-Analysis of C-Reactive Protein in Patients With Alzheimer's Disease. Am J Alzheimers Dis Other Demen 2016; 31:194-200. [PMID: 26340961 PMCID: PMC10852780 DOI: 10.1177/1533317515602087] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Inflammation may be associated with Alzheimer's disease (AD). This meta-analysis aimed to compare the level of C-reactive protein (CRP) in patients having AD to healthy controls. A total of 10 cross-sectional studies (n = 2093) were identified from PubMed and EMBASE after systematic searching and evaluation. The combined standardized mean difference (SMD) of CRP level between the disease and control group was analyzed. In the meta-analysis, there was no significant difference in serum between the CRP level of patients with AD and that of healthy controls (SMD: -0.400, 95% confidence interval [CI]: -0.827 to 0.027,P= .066). However, when we stratified the studies by Mini-Mental State Examination (MMSE) scores, the level of CRP in the mild and moderate dementia subgroup (MMSE ≥ 10) was significantly lower than that in the control group (SMD: -0.582, 95% CI: -0.957 to -0.208,P= .002). Therefore, the diagnostic value of CRP for mild and moderate AD may be useful in clinical practice.
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Affiliation(s)
- Changguo Gong
- School of Life Sciences, East China Normal University, Shanghai, PR China
| | - Daixin Wei
- School of Life Sciences, East China Normal University, Shanghai, PR China
| | - Ying Wang
- School of Life Sciences, East China Normal University, Shanghai, PR China
- Department of Physiology, Renji College, Wenzhou Medical University, Wenzhou, PR China
| | - Ji Ma
- School of Life Sciences, East China Normal University, Shanghai, PR China
| | - Chonggang Yuan
- School of Life Sciences, East China Normal University, Shanghai, PR China
| | - Wei Zhang
- School of Life Sciences, East China Normal University, Shanghai, PR China
| | - Guohua Yu
- School of Life Sciences, East China Normal University, Shanghai, PR China
| | - Yulan Zhao
- School of Life Sciences, East China Normal University, Shanghai, PR China
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Abstract
In 2003, academic staff members at The University of the West Indies Faculty of Medical Sciences St Augustine Trinidad and Tobago combined their expertise to make strides in Alzheimer's and Dementia research in Trinidad and Tobago. Dr. Nelleen Baboolal, Dr. Gershwin Davis and Professor Amanda McRae began developing a project that has produced significant results by examining not only the epidemiology of dementia, but the associated risk factors; caregiver burden and ultimately establishing biomarkers for the disease. This review is an account of our results from a decade of dementia research and how they are contributing toward mitigating the dementia tsunami in Trinidad and Tobago.
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Affiliation(s)
| | | | - Amanda McRae
- Department of Preclinical Sciences. Faculty of Medical Sciences, University of the West Indies, St Augustine
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Swardfager W, Lanctôt K, Rothenburg L, Wong A, Cappell J, Herrmann N. A meta-analysis of cytokines in Alzheimer's disease. Biol Psychiatry 2010; 68:930-41. [PMID: 20692646 DOI: 10.1016/j.biopsych.2010.06.012] [Citation(s) in RCA: 688] [Impact Index Per Article: 49.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 06/03/2010] [Accepted: 06/08/2010] [Indexed: 12/27/2022]
Abstract
BACKGROUND Studies suggest that inflammation is involved in the neurodegenerative cascade leading to Alzheimer's disease (AD) pathology and symptoms. This study sought to quantitatively summarize the clinical cytokine data. METHODS Original English language peer-reviewed studies measuring cytokine concentrations in AD and healthy control subjects were included. Mean (± standard deviation) cytokine concentrations for AD and control subjects were extracted. RESULTS Forty studies measuring peripheral blood cytokine concentrations and 14 measuring cerebrospinal fluid (CSF) cytokine concentrations were included. In peripheral blood, there were significantly higher concentrations (weighted mean difference [95% confidence interval]) of interleukin (IL)-6 (2.86 [1.68, 4.04] pg/mL, p < .00001, N[AD/control subjects] = 985/680, 14 studies), tumor necrosis factor (TNF)-α (3.25 [.76, 5.74] pg/mL, p = .01, N = 680/447, 14 studies), IL-1β (.55 [.32, .78] pg/mL, p < .00001, N = 574/370, 10 studies), transforming growth factor (TGF)-β (67.23 [28.62, 105.83] pg/mL, p = .0006, N = 190/158, 5 studies), IL-12 (7.60 [5.58, 9.62] pg/mL, p < .00001, N = 148/106, 5 studies), and IL-18 (15.82 [1.98, 29.66] pg/mL, p = .03, N = 131/94, 4 studies) but not of IL-4, IL-8, IL-10, interferon-γ, or C-reactive protein in AD subjects compared with control subjects. There were significantly higher concentrations of TGF-β (7.81 [2.27, 13.35] pg/mL, p =.006, N = 113/114, 5 studies) but not IL-6, TNF-α, and IL-1β in the CSF of AD subjects compared with control subjects. CONCLUSIONS These results strengthen the clinical evidence that AD is accompanied by an inflammatory response, particularly higher peripheral concentrations of IL-6, TNF-α, IL-1β, TGF-β, IL-12 and IL-18 and higher CSF concentrations of TGF-β.
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Affiliation(s)
- Walter Swardfager
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
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Lepara O, Alajbegovic A, Zaciragic A, Nakas-Icindic E, Valjevac A, Lepara D, Hadzovic-Dzuvo A, Fajkic A, Kulo A, Sofic E. Elevated serum homocysteine level is not associated with serum C-reactive protein in patients with probable Alzheimer’s disease. J Neural Transm (Vienna) 2009; 116:1651-6. [DOI: 10.1007/s00702-009-0325-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Accepted: 09/20/2009] [Indexed: 11/28/2022]
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Davis G, Baboolal N, Nayak S, McRae A. Sialic acid, homocysteine and CRP: potential markers for dementia. Neurosci Lett 2009; 465:282-4. [PMID: 19766699 DOI: 10.1016/j.neulet.2009.09.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Revised: 09/14/2009] [Accepted: 09/15/2009] [Indexed: 11/16/2022]
Abstract
To investigate whether sialic acid could discriminate between healthy age matched controls and patients with dementias of the Alzheimer's type (AD), and pure vascular dementia (VaD). 27 patients and 51 controls were administered the Mini-Mental State Examination (MMSE) and had blood analyzed for levels of total sialic acid, total homocysteine (tHcy), and C-reactive protein (CRP). Significant differences were found between the mean MMSE scores for patients with dementia compared with controls. Sialic acid levels were significantly higher in patients with AD compared with controls and homocysteine levels were higher in VaD. Sialic acid levels discriminated between patients with dementia of the Alzheimer's type and healthy controls only. The MMSE could discriminate between controls and patients with dementia but not between the subtypes and homocysteine was significant for patients with VaD.
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Affiliation(s)
- Gershwin Davis
- Department of Para Clinical Sciences, The University of the West Indies, St. Augustine, Trinidad and Tobago.
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Khan TK, Alkon DL. Early diagnostic accuracy and pathophysiologic relevance of an autopsy-confirmed Alzheimer's disease peripheral biomarker. Neurobiol Aging 2008; 31:889-900. [PMID: 18760507 DOI: 10.1016/j.neurobiolaging.2008.07.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 07/10/2008] [Accepted: 07/11/2008] [Indexed: 11/28/2022]
Abstract
Treatment of Alzheimer's disease (AD) and the discovery of promising drug candidates depend on early diagnosis. Few currently available diagnostic tests have significantly improved this early uncertainty, while the "gold standard" diagnosis continues to require clinical dementia in life and the presence of pathologic brain lesions of amyloid plaques and neurofibrillary tangles in the brain at autopsy. Here, the inflammatory agonist bradykinin, a small nano-peptide, that induces PKC-mediated phosphorylation of Erk1 and Erk2 in fibroblasts, was applied to punch-biopsy-obtained human skin fibroblasts. Quantitative imaging of the phosphorylated Erk1 and Erk2 bands was then used in a ratio that is mathematically configured into an AD-Biomarker Index (AD-Index). In the population described here (N=264), there were 64 autopsy examinations. Demented individuals were clinically diagnosed as AD with an overall accuracy of 78%. Among the 42 autopsy-confirmed cases for which there were also AD-Biomarker measurements, the overall accuracy of the AD-Biomarker was 98%. Among both the autopsy-confirmed and the clinically diagnosed patients, the AD-Index values were inversely correlated with the duration of disease, i.e., the time from the onset of dementia symptoms. Among the autopsy-confirmed cases, the AD-Biomarker diagnosis showed remarkably high sensitivity (97%) and specificity (100%) compared to clinical diagnosis (sensitivity: 78% and specificity: 20%). Using autopsy validation, the clinical diagnosis was only accurate at 52% level vs. the AD-Biomarker accuracy of 100% for cases with dementia not larger than 4 years of duration. Finally, application of soluble Abeta(1-42) to the fibroblasts of normal controls induced the abnormal AD-Biomarker phenotype, suggesting the pathophysiologic relevance of this AD-Biomarker measurement. In summary, the AD-Biomarker, as confirmed by autopsy validation, showed significantly higher sensitivity and specificity than did clinical diagnosis, particularly at early stages of disease, and pathophysiological relevance was demonstrated for the mechanistic basis of the AD-Biomarker measurements.
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Affiliation(s)
- Tapan Kumar Khan
- Blanchette Rockefeller Neurosciences Institute, West Virginia University, Morgantown, WV 26506-9301, USA
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