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Zhang J, He X, Liu Y, Cai Q, Chen H, Qing L. Multi-modal cross-attention network for Alzheimer's disease diagnosis with multi-modality data. Comput Biol Med 2023; 162:107050. [PMID: 37269680 DOI: 10.1016/j.compbiomed.2023.107050] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 04/26/2023] [Accepted: 05/03/2023] [Indexed: 06/05/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder, the most common cause of dementia, so the accurate diagnosis of AD and its prodromal stage mild cognitive impairment (MCI) is significant. Recent studies have demonstrated that multiple neuroimaging and biological measures contain complementary information for diagnosis. Many existing multi-modal models based on deep learning simply concatenate each modality's features despite substantial differences in representation spaces. In this paper, we propose a novel multi-modal cross-attention AD diagnosis (MCAD) framework to learn the interaction between modalities for better playing their complementary roles for AD diagnosis with multi-modal data including structural magnetic resonance imaging (sMRI), fluorodeoxyglucose-positron emission tomography (FDG-PET) and cerebrospinal fluid (CSF) biomarkers. Specifically, the imaging and non-imaging representations are learned by the image encoder based on cascaded dilated convolutions and CSF encoder, respectively. Then, a multi-modal interaction module is introduced, which takes advantage of cross-modal attention to integrate imaging and non-imaging information and reinforce relationships between these modalities. Moreover, an extensive objective function is designed to reduce the discrepancy between modalities for effectively fusing the features of multi-modal data, which could further improve the diagnosis performance. We evaluate the effectiveness of our proposed method on the ADNI dataset, and the extensive experiments demonstrate that our MCAD achieves superior performance for multiple AD-related classification tasks, compared to several competing methods. Also, we investigate the importance of cross-attention and the contribution of each modality to the diagnostics performance. The experimental results demonstrate that combining multi-modality data via cross-attention is helpful for accurate AD diagnosis.
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Affiliation(s)
- Jin Zhang
- College of Electronics and Information Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Xiaohai He
- College of Electronics and Information Engineering, Sichuan University, Chengdu, Sichuan, 610065, China.
| | - Yan Liu
- Department of Neurology, The Affiliated Hospital of Southwest Jiaotong University, The Third People's Hospital of Chengdu, Chengdu, Sichuan, 610031, China
| | - Qingyan Cai
- Department of Geriatric Medicine, The Fourth People's Hospital of Chengdu, Chengdu, Sichuan, 610036, China
| | - Honggang Chen
- College of Electronics and Information Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Linbo Qing
- College of Electronics and Information Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
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2
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The potential roles of excitatory-inhibitory imbalances and the repressor element-1 silencing transcription factor in aging and aging-associated diseases. Mol Cell Neurosci 2021; 117:103683. [PMID: 34775008 DOI: 10.1016/j.mcn.2021.103683] [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: 07/08/2021] [Revised: 11/02/2021] [Accepted: 11/06/2021] [Indexed: 12/28/2022] Open
Abstract
Disruptions to the central excitatory-inhibitory (E/I) balance are thought to be related to aging and underlie a host of neural pathologies, including Alzheimer's disease. Aging may induce an increase in excitatory signaling, causing an E/I imbalance, which has been linked to shorter lifespans in mice, flies, and worms. In humans, extended longevity correlates to greater repression of genes involved in excitatory neurotransmission. The repressor element-1 silencing transcription factor (REST) is a master regulator in neural cells and is believed to be upregulated with senescent stimuli, whereupon it counters hyperexcitability, insulin/insulin-like signaling pathway activity, oxidative stress, and neurodegeneration. This review examines the putative mechanisms that distort the E/I balance with aging and neurodegeneration, and the putative roles of REST in maintaining neuronal homeostasis.
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Zulfiqar S, Garg P, Nieweg K. Contribution of astrocytes to metabolic dysfunction in the Alzheimer's disease brain. Biol Chem 2020; 400:1113-1127. [PMID: 31188740 DOI: 10.1515/hsz-2019-0140] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 05/28/2019] [Indexed: 11/15/2022]
Abstract
Historically considered as accessory cells to neurons, there is an increasing interest in the role of astrocytes in normal and pathological conditions. Astrocytes are involved in neurotransmitter recycling, antioxidant supply, ion buffering and neuroinflammation, i.e. a lot of the same pathways that go astray in Alzheimer's disease (AD). AD remains the leading cause of dementia in the elderly, one for which there is still no cure. Efforts in AD drug development have largely focused on treating neuronal pathologies that appear relatively late in the disease. The neuroenergetic hypothesis, however, focuses on the early event of glucose hypometabolism in AD, where astrocytes play a key role, caused by an imbalanced neuron-astrocyte lactate shuttle. This further results in a state of oxidative stress and neuroinflammation, thereby compromising the integrity of astrocyte-neuron interaction. Compromised astrocytic energetics also enhance amyloid generation, further increasing the severity of the disease. Additionally, apolipoprotein E (APOE), the major genetic risk factor for AD, is predominantly secreted by astrocytes and plays a critical role in amyloid clearance and regulates glucose metabolism in an amyloid-independent manner. Thus, boosting the neuroprotective properties of astrocytes has potential applications in delaying the onset and progression of AD. This review explores how the metabolic dysfunction arising from astrocytes acts as a trigger for the development of AD.
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Affiliation(s)
- Shadaan Zulfiqar
- Institute for Pharmacology and Clinical Pharmacy, Philipps University, Karl-von-Frisch Strasse, Marburg D-35043, Germany.,Marburg Center for Mind, Brain and Behavior, Philipps University, Marburg, Germany
| | - Pretty Garg
- Institute for Pharmacology and Clinical Pharmacy, Philipps University, Karl-von-Frisch Strasse, Marburg D-35043, Germany.,Marburg Center for Mind, Brain and Behavior, Philipps University, Marburg, Germany.,Institute for Neuro and Sensory Physiology, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Katja Nieweg
- Institute for Pharmacology and Clinical Pharmacy, Philipps University, Karl-von-Frisch Strasse, Marburg D-35043, Germany.,Marburg Center for Mind, Brain and Behavior, Philipps University, Marburg, Germany
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Benvenutto A, Giusiano B, Koric L, Gueriot C, Didic M, Felician O, Guye M, Guedj E, Ceccaldi M. Imaging Biomarkers of Neurodegeneration in Alzheimer's Disease: Distinct Contributions of Cortical MRI Atrophy and FDG-PET Hypometabolism. J Alzheimers Dis 2019; 65:1147-1157. [PMID: 30124446 DOI: 10.3233/jad-180292] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Neurodegeneration biomarkers are routinely used in the diagnosis of Alzheimer's disease (AD). OBJECTIVE To evaluate the respective contributions of two neuroimaging biomarkers, structural MRI and 18FDG-PET, in the assessment of neurodegeneration in AD dementia. METHODS Patients with mild AD dementia diagnosed based on clinical and cerebrospinal fluid criteria and cognitively healthy subjects, from the Marseille cohort ADAge with cognitive, structural MRI and 18FDG-PET assessments, were included. Extent of atrophy on MRI and of hypometabolism on 18FDG-PET were individually evaluated in each patient using a voxel-based analysis on whole-brain approach and compared to healthy subjects. Patients were divided in distinct groups according to their atrophy extent on the one hand and to their hypometabolism extent on the other, then, to their imaging profile combining the extent of the two biomarkers. RESULTS Fifty-two patients were included. The MMSE score was significantly lower in the "Extensive hypometabolism" group than in the "Limited hypometabolism" group (respectively 19.5/30 versus 23/30). A lower Innotest Amyloid Tau Index was associated with an extensive hypometabolism (p = 0.04). There were more patients with low educational level in the "Extensive atrophy" group, while a higher educational level was more found in the "Limited atrophy" group (p = 0.005). CONCLUSION 18FDG-PET hypometabolism extent is associated with the pathological processes and clinical severity of AD, while MRI atrophy seems to be influenced by the cognitive reserve. In the context of mild AD dementia, these two biomarkers of neurodegeneration are thus not interchangeable and require to be considered in combination rather than in isolation.
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Affiliation(s)
- Agnès Benvenutto
- Neurology and Neuropsychology Department and CMMR PACA Ouest, Assistance Publique-Hôpitaux de Marseille, Marseille, France
| | - Bernard Giusiano
- Department of Public Health, Assistance Publique-Hôpitaux de Marseille, Marseille, France.,Institut de Neurosciences des Systèmes, Aix-Marseille Univ, INSERM UMR 1106, Marseille, France
| | - Lejla Koric
- Neurology and Neuropsychology Department and CMMR PACA Ouest, Assistance Publique-Hôpitaux de Marseille, Marseille, France.,Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France
| | - Claude Gueriot
- Neurology and Neuropsychology Department and CMMR PACA Ouest, Assistance Publique-Hôpitaux de Marseille, Marseille, France
| | - Mira Didic
- Neurology and Neuropsychology Department and CMMR PACA Ouest, Assistance Publique-Hôpitaux de Marseille, Marseille, France.,Institut de Neurosciences des Systèmes, Aix-Marseille Univ, INSERM UMR 1106, Marseille, France
| | - Olivier Felician
- Neurology and Neuropsychology Department and CMMR PACA Ouest, Assistance Publique-Hôpitaux de Marseille, Marseille, France.,Institut de Neurosciences des Systèmes, Aix-Marseille Univ, INSERM UMR 1106, Marseille, France
| | - Maxime Guye
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, Timone University Hospital, CEMEREM, Marseille, France
| | - Eric Guedj
- Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.,Department of Nuclear Medecine, Assistance Publique-Hôpitaux de Marseille, Marseille, France.,CERIMED, Aix-Marseille Univ, Marseille, France
| | - Mathieu Ceccaldi
- Neurology and Neuropsychology Department and CMMR PACA Ouest, Assistance Publique-Hôpitaux de Marseille, Marseille, France.,Institut de Neurosciences des Systèmes, Aix-Marseille Univ, INSERM UMR 1106, Marseille, France
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5
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Zhu QB, Bao AM, Swaab D. Activation of the Brain to Postpone Dementia: A Concept Originating from Postmortem Human Brain Studies. Neurosci Bull 2019; 35:253-266. [PMID: 30721394 PMCID: PMC6426905 DOI: 10.1007/s12264-019-00340-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 10/29/2018] [Indexed: 01/27/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by decreased neuronal activity and atrophy, while hyperactivity of neurons seems to make them resistant to aging and neurodegeneration, a phenomenon which we have paraphrased as 'use it or lose it'. Our hypothesis proposes that (1) during their functioning, neurons are damaged; (2) accumulation of damage that is not repaired is the basis of aging; (3) the vulnerability to AD is determined by the genetic background and the balance between the amount of damage and the efficiency of repair, and (4) by stimulating the brain, repair mechanisms are stimulated and cognitive reserve is increased, resulting in a decreased rate of aging and risk for AD. Environmental stimulating factors such as bilingualism/multilingualism, education, occupation, musical experience, physical exercise, and leisure activities have been reported to reduce the risk of dementia and decrease the rate of cognitive decline, although methodological problems are present.
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Affiliation(s)
- Qiong-Bin Zhu
- Department of Neurology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020, China
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Ai-Min Bao
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, 310058, China.
| | - Dick Swaab
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, 310058, China
- Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
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6
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Longitudinal tau and metabolic PET imaging in relation to novel CSF tau measures in Alzheimer's disease. Eur J Nucl Med Mol Imaging 2019; 46:1152-1163. [PMID: 30610252 PMCID: PMC6451715 DOI: 10.1007/s00259-018-4242-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/11/2018] [Indexed: 12/02/2022]
Abstract
Purpose Studies comparing CSF and PET tau biomarkers have included only commercial CSF assays examining specific phosphorylation sites (e.g. threonine 181, P-tau181p) and mid-domain tau (i.e. total tau, T-tau). Moreover, these studies did not examine CSF tau levels in relation to cerebral glucose metabolism. We thus aimed to examine CSF tau measures, using both commercial and novel assays, in relation to [18F]THK5317 (tau) and [18F]FDG PET (glucose metabolism). Methods Fourteen Alzheimer’s disease (AD) patients (seven prodromal, seven dementia) underwent [18F]THK5317 and [18F]FDG PET studies, with follow-up performed in ten subjects (six prodromal, four dementia) after 17 months. In addition to commercial assays, novel measures capturing N-terminus+mid-domain (tau N-Mid) and C-terminally truncated (tau-368) fragments were included. Results While the levels of all forms of CSF tau were found to be inversely associated with baseline [18F]FDG uptake, associations with baseline [18F]THK5317 uptake varied in relation to the degree of isocortical hypometabolism ([18F]FDG SUVR). Changes in the levels of the novel CSF markers tracked longitudinal changes in tracer uptake better than changes in P-tau181p and T-tau levels, and improved concordance with dichotomized regional [18F]THK5317 measures. Conclusion Our findings suggest that neurodegeneration may modulate the relationship between CSF and PET tau biomarkers, and that, by comparison to P-tau181p and T-tau, tau-368 and tau N-Mid may better capture tau pathology and synaptic impairment. Electronic supplementary material The online version of this article (10.1007/s00259-018-4242-6) contains supplementary material, which is available to authorized users.
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7
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Geijselaers SLC, Aalten P, Ramakers IHGB, De Deyn PP, Heijboer AC, Koek HL, OldeRikkert MGM, Papma JM, Reesink FE, Smits LL, Stehouwer CDA, Teunissen CE, Verhey FRJ, van der Flier WM, Biessels GJ. Association of Cerebrospinal Fluid (CSF) Insulin with Cognitive Performance and CSF Biomarkers of Alzheimer's Disease. J Alzheimers Dis 2018; 61:309-320. [PMID: 29154275 PMCID: PMC5734123 DOI: 10.3233/jad-170522] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Background: Abnormal insulin signaling in the brain has been linked to Alzheimer’s disease (AD). Objective: To evaluate whether cerebrospinal fluid (CSF) insulin levels are associated with cognitive performance and CSF amyloid-β and Tau. Additionally, we explore whether any such association differs by sex or APOE ɛ4 genotype. Methods: From 258 individuals participating in the Parelsnoer Institute Neurodegenerative Diseases, a nationwide multicenter memory clinic population, we selected 138 individuals (mean age 66±9 years, 65.2% male) diagnosed with subjective cognitive impairment (n = 45), amnestic mild cognitive impairment (n = 44), or AD (n = 49), who completed a neuropsychological assessment, including tests of global cognition and memory performance, and who underwent lumbar puncture. We measured CSF levels of insulin, amyloid-β1-42, total (t-)Tau, and phosphorylated (p-)Tau. Results: CSF insulin levels did not differ between the diagnostic groups (p = 0.136). Across the whole study population, CSF insulin was unrelated to cognitive performance and CSF biomarkers of AD, after adjustment for age, sex, body mass index, diabetes status, and clinic site (all p≥0.131). Importantly, however, we observed effect modification by sex and APOE ɛ4 genotype. Specifically, among women, higher insulin levels in the CSF were associated with worse global cognition (standardized regression coefficient –0.483; p = 0.008) and higher p-Tau levels (0.353; p = 0.040). Among non-carriers of the APOE ɛ4 allele, higher CSF insulin was associated with higher t-Tau (0.287; p = 0.008) and p-Tau (0.246; p = 0.029). Conclusion: Our findings provide further evidence for a relationship between brain insulin signaling and AD pathology. It also highlights the need to consider sex and APOE ɛ4 genotype when assessing the role of insulin.
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Affiliation(s)
- Stefan L C Geijselaers
- Departments of Neurology and Geriatrics Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands.,Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Centre +, Maastricht, the Netherlands
| | - Pauline Aalten
- Alzheimer Centre Limburg, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Centre +, Maastricht, the Netherlands
| | - Inez H G B Ramakers
- Alzheimer Centre Limburg, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Centre +, Maastricht, the Netherlands
| | - Peter Paul De Deyn
- Department of Neurology and Alzheimer Research Centre, University of Groningen, University Medical Centre Groningen, Groningen, the Netherlands
| | - Annemieke C Heijboer
- Department of Clinical Chemistry, Endocrine Laboratory, VU University Medical Centre, Amsterdam, the Netherlands
| | - Huiberdina L Koek
- Departments of Neurology and Geriatrics Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Marcel G M OldeRikkert
- Radboudumc Alzheimer Centre, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Janne M Papma
- Departments of Neurology and Radiology, Erasmus University Medical Centre, Rotterdam, the Netherlands
| | - Fransje E Reesink
- Department of Neurology and Alzheimer Research Centre, University of Groningen, University Medical Centre Groningen, Groningen, the Netherlands
| | - Lieke L Smits
- Alzheimer Centre Amsterdam, VU University Medical Centre, Amsterdam, the Netherlands
| | - Coen D A Stehouwer
- Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Centre +, Maastricht, the Netherlands
| | - Charlotte E Teunissen
- Department of Clinical Chemistry, Neurochemistry Laboratory and Biobank, VU University Medical Centre, Amsterdam, the Netherlands
| | - Frans R J Verhey
- Alzheimer Centre Limburg, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Centre +, Maastricht, the Netherlands
| | | | - Geert Jan Biessels
- Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Centre +, Maastricht, the Netherlands
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Mattson MP, Arumugam TV. Hallmarks of Brain Aging: Adaptive and Pathological Modification by Metabolic States. Cell Metab 2018; 27:1176-1199. [PMID: 29874566 PMCID: PMC6039826 DOI: 10.1016/j.cmet.2018.05.011] [Citation(s) in RCA: 610] [Impact Index Per Article: 101.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/02/2018] [Accepted: 05/15/2018] [Indexed: 02/06/2023]
Abstract
During aging, the cellular milieu of the brain exhibits tell-tale signs of compromised bioenergetics, impaired adaptive neuroplasticity and resilience, aberrant neuronal network activity, dysregulation of neuronal Ca2+ homeostasis, the accrual of oxidatively modified molecules and organelles, and inflammation. These alterations render the aging brain vulnerable to Alzheimer's and Parkinson's diseases and stroke. Emerging findings are revealing mechanisms by which sedentary overindulgent lifestyles accelerate brain aging, whereas lifestyles that include intermittent bioenergetic challenges (exercise, fasting, and intellectual challenges) foster healthy brain aging. Here we provide an overview of the cellular and molecular biology of brain aging, how those processes interface with disease-specific neurodegenerative pathways, and how metabolic states influence brain health.
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Affiliation(s)
- Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Thiruma V Arumugam
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
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Rubí S, Noguera A, Tarongí S, Oporto M, García A, Vico H, Espino A, Picado M, Mas A, Peña C, Amer G. Concordance between brain 18 F-FDG PET and cerebrospinal fluid biomarkers in diagnosing Alzheimer's disease. Rev Esp Med Nucl Imagen Mol 2018. [DOI: 10.1016/j.remnie.2017.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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10
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Brain metabolic correlates of CSF Tau protein in a large cohort of Alzheimer's disease patients: A CSF and FDG PET study. Brain Res 2017; 1678:116-122. [PMID: 29066367 DOI: 10.1016/j.brainres.2017.10.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 10/04/2017] [Accepted: 10/16/2017] [Indexed: 11/23/2022]
Abstract
AIMS Physiopathological mechanisms of Alzheimer's disease (AD) are still matter of debate. Especially the role of amyloid β and tau pathology in the development of the disease are still matter of debate. Changes in tau and amyloid β peptide concentration in cerebrospinal fluid (CSF) and hypometabolic patterns at fluorine-18 fluorodeoxyglucose (18F-FDG) PET scanning are considered as biomarkers of AD. The present study was aimed to evaluate the relationships between the concentrations of CSF total Tau (t-Tau), phosphorilated Tau (p-Tau) and Aβ1-42 amyloid peptide with 18F-FDG brain distribution in a group of patients with AD. MATERIALS AND METHODS We examined 131 newly diagnosed AD patients according to the NINCDS-ADRDA criteria and 20 healthy controls. The mean (±SD) age of the patients was 70 (±7) years; 57 were male and 74 were female. All patients and controls underwent a complete clinical investigation, including medical history, neurological examination, mini-mental state examination (MMSE), a complete blood screening (including routine exams, thyroid hormones and a complete neuropsychological evaluation). Structural MRI was performed not earlier than 1 month before the 18F-FDG PET/CT. The following patients were excluded: those with isolated deficits and/or unmodified MMSE (=25/30) on revisit (period of follow-up: 6, 12 and 18 months); patients who had had a clinically manifest acute stroke in the last 6 months with a Hachinsky score greater than 4; and patients with radiological evidence of subcortical lesions. All AD patients were taken off cholinesterase inhibitor treatment throughout the study. We performed lumbar puncture and CSF sampling for diagnostic purposes 2 weeks (±2 days) before the PET/CT scan. The relationship between brain F-FDG uptake and CSF biomarkers was analysed using statistical parametric mapping (SPM8; Wellcome Department of Cognitive Neurology, London, UK) implemented in Matlab R2012b using the MMSE score, sex and age, and other CSF biomarkers as covariates. RESULTS t-Tau, p-Tau and Aβ(1-42) in CSF resulted 774 ± 345 pg/ml, 98 ± 64 pg/ml and 348.8 ± 111 pg/ml respectively. SPM analysis showed a significant negative correlation between CSF t-Tau and 18F FDG uptake in right temporal, parietal and frontal lobe (Brodmann areas, BA, 20, 40 and 8; P fdr and few corr < 0.001, ke 19534). We did not find any significant relationships with other CSF biomarkers. CONCLUSIONS t-Tau deposition in brain is related to temporal, parietal and frontal hypometabolism in AD.
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11
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Sheikh-Bahaei N, Sajjadi SA, Manavaki R, Gillard JH. Imaging Biomarkers in Alzheimer's Disease: A Practical Guide for Clinicians. J Alzheimers Dis Rep 2017; 1:71-88. [PMID: 30480230 PMCID: PMC6159632 DOI: 10.3233/adr-170013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Although recent developments in imaging biomarkers have revolutionized the diagnosis of Alzheimer’s disease at early stages, the utility of most of these techniques in clinical setting remains unclear. The aim of this review is to provide a clear stepwise algorithm on using multitier imaging biomarkers for the diagnosis of Alzheimer’s disease to be used by clinicians and radiologists for day-to-day practice. We summarized the role of most common imaging techniques and their appropriate clinical use based on current consensus guidelines and recommendations with brief sections on acquisition and analysis techniques for each imaging modality. Structural imaging, preferably MRI or alternatively high resolution CT, is the essential first tier of imaging. It improves the accuracy of clinical diagnosis and excludes other potential pathologies. When the results of clinical examination and structural imaging, assessed by dementia expert, are still inconclusive, functional imaging can be used as a more advanced option. PET with ligands such as amyloid tracers and 18F-fluorodeoxyglucose can improve the sensitivity and specificity of diagnosis particularly at the early stages of the disease. There are, however, limitations in using these techniques in wider community due to a combination of lack of facilities and expertise to interpret the findings. The role of some of the more recent imaging techniques including tau imaging, functional MRI, or diffusion tensor imaging in clinical practice, remains to be established in the ongoing and future studies.
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Affiliation(s)
- Nasim Sheikh-Bahaei
- Department of Radiology, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | | | - Roido Manavaki
- Department of Radiology, University of Cambridge School of Clinical Medicine, Cambridge, UK
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12
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Hall B, Mak E, Cervenka S, Aigbirhio FI, Rowe JB, O’Brien JT. In vivo tau PET imaging in dementia: Pathophysiology, radiotracer quantification, and a systematic review of clinical findings. Ageing Res Rev 2017; 36:50-63. [PMID: 28315409 DOI: 10.1016/j.arr.2017.03.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/15/2017] [Accepted: 03/06/2017] [Indexed: 12/14/2022]
Abstract
In addition to the deposition of β-amyloid plaques, neurofibrillary tangles composed of aggregated hyperphosphorylated tau are one of the pathological hallmarks of Alzheimer's disease and other neurodegenerative disorders. Until now, our understanding about the natural history and topography of tau deposition has only been based on post-mortem and cerebrospinal fluid studies, and evidence continues to implicate tau as a central driver of downstream neurodegenerative processes and cognitive decline. Recently, it has become possible to assess the regional distribution and severity of tau burden in vivo with the development of novel radiotracers for positron emission tomography (PET) imaging. In this article, we provide a comprehensive discussion of tau pathophysiology, its quantification with novel PET radiotracers, as well as a systematic review of tau PET imaging in normal aging and various dementia conditions: mild cognitive impairment, Alzheimer's disease, frontotemporal dementia, progressive supranuclear palsy, and Lewy body dementia. We discuss the main findings in relation to group differences, clinical-cognitive correlations of tau PET, and multi-modal relationships among tau PET and other pathological markers. Collectively, the small but growing literature of tau PET has yielded consistent anatomical patterns of tau accumulation that recapitulate post-mortem distribution of neurofibrillary tangles which correlate with cognitive functions and other markers of pathology. In general, AD is characterised by increased tracer retention in the inferior temporal lobe, extending into the frontal and parietal regions in more severe cases. It is also noted that the spatial topography of tau accumulation is markedly distinct to that of amyloid burden in aging and AD. Tau PET imaging has also revealed characteristic spatial patterns among various non-AD tauopathies, supporting its potential role for differential diagnosis. Finally, we propose novel directions for future tau research, including (a) longitudinal imaging in preclinical dementia, (b) multi-modal mapping of tau pathology onto other pathological processes such as neuroinflammation, and (c) the need for more validation studies against post-mortem samples of the same subjects.
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13
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Concordance between brain 18F-FDG PET and cerebrospinal fluid biomarkers in diagnosing Alzheimer's disease. Rev Esp Med Nucl Imagen Mol 2017. [PMID: 28645685 DOI: 10.1016/j.remn.2017.05.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Cortical posterior hypometabolism on PET imaging with 18F-FDG (FDG-PET), and altered levels of Aß1-42 peptide, total Tau (tTau) and phosphorylated Tau (pTau) proteins in cerebrospinal fluid (CSF) are established diagnostic biomarkers in Alzheimer's disease (AD). An evaluation has been made of the concordance and relationship between the results of FDG-PET and CSF biomarkers in symptomatic patients with suspected AD. MATERIAL AND METHODS A retrospective review was carried out on 120 patients with cognitive impairment referred to our Cognitive Neurology Unit, and who were evaluated by brain FDG-PET and a lumbar puncture for CSF biomarkers. In order to calculate their Kappa coefficient of concordance, the result of the FDG-PET and the set of the three CSF biomarkers in each patient was classified as normal, inconclusive, or AD-compatible. The relationship between the results of both methods was further assessed using logistic regression analysis, including the Aß1-42, tTau and pTau levels as quantitative predictors, and the FDG-PET result as the dependent variable. RESULTS The weighted Kappa coefficient between FDG-PET and CSF biomarkers was 0.46 (95% CI: 0.35-0.57). Logistic regression analysis showed that the Aß1-42 and tTau values together were capable of discriminating an FDG-PET result metabolically suggestive of AD from one non-suggestive of AD, with a 91% sensitivity and 93% specificity at the cut-off line Aß1-42=44+1.3×tTau. CONCLUSIONS The level of concordance between FDG-PET and CSF biomarkers was moderate, indicating their complementary value in diagnosing AD. The Aß1-42 and tTau levels in CSF help to predict the patient FDG-PET cortical metabolic status.
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Affiliation(s)
- Karl Herholz
- Wolfson Molecular Imaging Centre, Institute of Brain, Behaviour and Mental Health, University of Manchester, 27 Palatine Road, Manchester, M203LJ, UK.
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Andriuta D, Moullart V, Schraen S, Devendeville A, Meyer ME, Godefroy O. What are the Most Frequently Impaired Markers of Neurodegeneration in ADNI Subjects? J Alzheimers Dis 2016; 51:793-800. [PMID: 26923012 DOI: 10.3233/jad-150829] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to examine the relationship between cerebrospinal fluid (CSF) levels of biomarkers for Alzheimer's disease (AD) (Aβ1-42, t-tau, and p-tau) and 18Fluorodeoxyglucose positron emission tomography (FDG-PET) hypometabolism in subjects from the Alzheimer's Disease Neuroimaging Initiative, and specifically to determine which index of neurodegeneration was most frequently affected. The secondary objective was to determine the most frequently hypometabolic region in patients with a CSF AD signature (abnormal Aβ1-42 and abnormal p-tau). We included the 372 subjects (85 normal subjects, 212 patients with mild cognitive impairment, and 75 patients with AD) with a CSF biomarker dosage (Aβ1-42, t-tau, and p-tau) and brain FDG-PET. The relationship between FDG-PET metabolism (in five regions of interest (ROI) known to be damaged in AD) and CSF t-tau and p-tau levels was studied as a function of CSF Aβ1-42 status. FDG-PET hypometabolism and CSF t-tau and p-tau levels were correlated only in patients with an abnormal CSF Aβ1-42 level (t-tau: R2 = 0.044, p = 0.001; p-tau: R2 = 0.02, p = 0.03). In the latter patients, CSF p-tau was the most frequently (p = 0.0001) abnormal neurodegeneration marker (p-tau: 92.8%; FDG-PET: 56.5%; CSF t-tau: 59.1%). Within the five ROI of FDG PET, the angular gyrus metabolism (R2 = 0.149; p = 0.0001) was selected as the most tightly associated with CSF AD signature. The relation between CSF markers of neurodegeneration (p-tau and t-tau) and brain hypometabolism (in FDG-PET) is conditioned by presence of amyloid abnormality. This finding supports the current physiopathological model of AD. P-tau is the most frequently impaired biomarker. Using FDG PET angular gyrus hypometabolism is the most sensitive to CSF-biomarker-defined AD.
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Affiliation(s)
- Daniela Andriuta
- Department of Neurology and Laboratory of Functional Neurosciences, University Hospital of Amiens, France
| | | | - Susanna Schraen
- Department of Biology and Pathology, Lille University Hospital, France
| | - Agnes Devendeville
- Department of Neurology and Laboratory of Functional Neurosciences, University Hospital of Amiens, France.,Department of Gerontology, University Hospital of Amiens, France
| | | | - Olivier Godefroy
- Department of Neurology and Laboratory of Functional Neurosciences, University Hospital of Amiens, France
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Gao R, Zhang G, Chen X, Yang A, Smith G, Wong DF, Zhou Y. CSF Biomarkers and Its Associations with 18F-AV133 Cerebral VMAT2 Binding in Parkinson's Disease-A Preliminary Report. PLoS One 2016; 11:e0164762. [PMID: 27764160 PMCID: PMC5072678 DOI: 10.1371/journal.pone.0164762] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 09/30/2016] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Cerebrospinal fluid (CSF) biomarkers, such as α-synuclein (α-syn), amyloid beta peptide 1-42 (Aβ1-42), phosphorylated tau (181P) (p-tau), and total tau (t-tau), have long been associated with the development of Parkinson disease (PD) and other neurodegenerative diseases. In this investigation, we reported the assessment of CSF biomarkers and their correlations with vesicular monoamine transporter 2 (VMAT2) bindings measured with 18F-9-fluoropropyl-(+)-dihydrotetrabenazine (18F-AV133) that is being developed as a biomarker for PD. We test the hypothesis that monoaminergic degeneration was correlated with CSF biomarker levels in untreated PD patients. METHODS The available online data from the Parkinson's Progression Markers Initiative study (PPMI) project were collected and analyzed, which include demographic information, clinical evaluations, CSF biomarkers (α-syn, Aβ1-42, p-tau, and t-tau), 18F-AV133 brain PET, and T1 weighted MRIs. Region of interest (ROI) and voxel-wise Pearson correlation between standardized uptake value ratio (SUVR) and CSF biomarkers were calculated. RESULTS Our major findings are: 1) Compared with controls, CSF α-syn and tau levels decreased significantly in PD; 2) α-syn was closely correlated with Aβ1-42 and tau in PD, especially in early-onset patients; and 3) hypothesis-driven ROI analysis found a significant negative correlation between CSF Aβ1-42 levels and VMAT2 densities in post cingulate, left caudate, left anterior putamen, and left ventral striatum in PDs. CSF t-tau and p-tau levels were significantly negatively related to VMAT2 SUVRs in substantia nigra and left ventral striatum, respectively. Voxel-wise analysis showed that left caudate, parahippocampal gyrus, insula and temporal lobe were negatively correlated with Aβ1-42. In addition, superior frontal gyrus and transverse temporal gyrus were negatively correlated with CSF p-tau levels. CONCLUSION These results suggest that monoaminergic degeneration in PD is correlated with CSF biomarkers associated with cognitive impairment in neurodegenerative diseases including Alzheimer's disease. The association between loss of dopamine synaptic function and pathologic protein accumulations in PD indicates an important role of CSF biomarkers in PD development.
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Affiliation(s)
- Rui Gao
- Department of Nuclear Medicine, the First Affiliated Hospital of Xian Jiaotong University, Xi'an, Shaanxi 710061, China
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, United States of America
| | - Guangjian Zhang
- Department of Surgery, the First Affiliated Hospital of Xian Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Xueqi Chen
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, United States of America
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Aimin Yang
- Department of Nuclear Medicine, the First Affiliated Hospital of Xian Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Gwenn Smith
- Division of Geriatric Psychiatry and Neuropsychiatry, Johns Hopkins Bayview Medical Center, Baltimore, Maryland 21287, United States of America
| | - Dean F. Wong
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, United States of America
- Department of Psychiatry, Johns Hopkins University, Baltimore, Maryland 21205, United States of America
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland 21205, United States of America
- Department of Neuroscience, Johns Hopkins University, Baltimore, Maryland 21205, United States of America
| | - Yun Zhou
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, United States of America
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Valkanova V, Ebmeier KP. Neuroimaging in dementia. Maturitas 2014; 79:202-8. [PMID: 24685291 DOI: 10.1016/j.maturitas.2014.02.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 02/25/2014] [Accepted: 02/28/2014] [Indexed: 10/25/2022]
Abstract
Over the last few years, advances in neuroimaging have generated biomarkers, which increase diagnostic certainty, provide valuable information about prognosis, and suggest a particular pathology underlying the clinical dementia syndrome. We aim to review the evidence for use of already established imaging modalities, along with selected techniques that have a great potential to guide clinical decisions in the future. We discuss structural, functional and molecular imaging, focusing on the most common dementias: Alzheimer's disease, fronto-temporal dementia, dementia with Lewy bodies and vascular dementia. Finally, we stress the importance of conducting research using representative cohorts and in a naturalistic set up, in order to build a strong evidence base for translating imaging methods for a National Health Service. If we assess a broad range of patients referred to memory clinic with a variety of imaging modalities, we will make a step towards accumulating robust evidence and ultimately closing the gap between the dramatic advances in neurosciences and meaningful clinical applications for the maximum benefit of our patients.
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Affiliation(s)
- Vyara Valkanova
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
| | - Klaus P Ebmeier
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK.
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Varga J, Klausz B, Domokos Á, Kálmán S, Pákáski M, Szűcs S, Garab D, Zvara Á, Puskás L, Kálmán J, Tímár J, Bagdy G, Zelena D. Increase in Alzheimer's related markers preceeds memory disturbances: Studies in vasopressin-deficient Brattleboro rat. Brain Res Bull 2014; 100:6-13. [DOI: 10.1016/j.brainresbull.2013.10.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 10/18/2013] [Accepted: 10/21/2013] [Indexed: 11/25/2022]
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Yeo JM, Lim X, Khan Z, Pal S. Systematic review of the diagnostic utility of SPECT imaging in dementia. Eur Arch Psychiatry Clin Neurosci 2013; 263:539-52. [PMID: 23917803 DOI: 10.1007/s00406-013-0426-z] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 07/08/2013] [Indexed: 12/20/2022]
Abstract
Single-photon emission-computed tomography (SPECT) may potentially contribute to the diagnostic work up of patients with neurodegenerative dementia. This systematic review aims to establish the diagnostic utility of 99mTc-hexamethylpropyleneamine (99mTc-HMPAO) and 99mTc-ethylcysteine dimer SPECT in distinguishing between Alzheimer's disease (AD) and frontotemporal dementia (FTD), AD and vascular dementia (VD), AD and dementia with Lewy bodies (DLB), and AD and normal controls (NC). We searched MEDLINE and Embase databases via OVID for articles from January 1985 to May 2012 and identified additional studies from reviews and references. Of 755 studies, 49 studies met the inclusion and exclusion criteria for this systematic review; AD versus FTD (n=13), AD versus VD (n=18), AD versus DLB (n=5), and AD versus NC (n=18). We compiled relevant data and graded the studies with an internal and external validity criteria checklist. We pooled the studies with a clinical diagnosis and those using 99mTc-HMPAO SPECT in a meta-analysis, calculating the pooled weighted sensitivity, specificity, likelihood ratios, and diagnostic odds ratios using DerSimonian-Laird random-effects model. The pooled weighted sensitivity and specificity of 99mTc-HMPAO-SPECT in distinguishing clinically diagnosed AD from FTD are 79.7 and 79.9%, respectively, AD from VD are 74.5 and 72.4%, AD from DLB are 70.2 and 76.2%, and AD from NC are 76.1 and 85.4%. SPECT does have diagnostic value, particularly in differentiating Alzheimer's disease from frontotemporal dementia and normal controls; however, it should not be used in isolation, rather as an adjunct, and interpreted in the context of clinical information and paraclinical test results.
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Affiliation(s)
- Jing Ming Yeo
- College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK,
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20
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Tabaraud F, Leman JP, Milor AM, Roussie JM, Barrière G, Tartary M, Boutros-Toni F, Rigaud M. Alzheimer CSF biomarkers in routine clinical setting. Acta Neurol Scand 2012; 125:416-23. [PMID: 21954973 DOI: 10.1111/j.1600-0404.2011.01592.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Our work was aimed to evaluate Alzheimer's disease diagnosis improvement using cerebrospinal fluid biomarkers (CSF) in neurological daily practice. MATERIALS AND METHODS For this purpose, 150 patients clinically and neurochemically classified as having AD or cognitive impairment with or without other dementia type were included in the study. The following CSF peptides were studied, blindly to the clinical diagnosis: beta-amyloid(1-42) peptide (Aβ(1-42)), Tau (T-tau), threonine-181 hyperphosphorylated tau protein (P-tau(181)), and beta-amyloid(1-40) peptide (Aβ(1-40)). From these measurements, Innotest® Amyloid Tau Index (IATI) was calculated for each patient. RESULTS This assessment allowed to separate 83 biochemical profiles of AD and 67 non-Alzheimer's disease (non-AD), both AD and non-AD categories match with clinical data amounting to 73% and 90%, respectively. Among mild cognitive impairment (MCI) patients, CSF biomarkers led to discriminate those who are likely to be AD. We devoted a special section to Aβ(1-40) which is not a routine parameter but can help to confirm a pathological amyloid process as Aβ(1-42)/Aβ(1-40) ratio underlining the real decline of the Aβ(1-42). CONCLUSIONS The interest of biomarkers and their ability to solve awkward cases were carefully noticed all the more when a discrepancy between clinical and CSF biological data was involved. The final proposed algorithm allowed to identify pathogenic forms of AD according to the prevailing role of hyperphosphorylated tau or amyloid beta peptide.
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Affiliation(s)
- F Tabaraud
- Clinical Center, Clinique du Colombier, Limoges, France
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Brusa L, Ceravolo R, Kiferle L, Monteleone F, Iani C, Schillaci O, Stanzione P, Koch G. Metabolic changes induced by theta burst stimulation of the cerebellum in dyskinetic Parkinson’s disease patients. Parkinsonism Relat Disord 2012; 18:59-62. [DOI: 10.1016/j.parkreldis.2011.08.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 08/22/2011] [Accepted: 08/23/2011] [Indexed: 12/19/2022]
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Abstract
Clinical use of positron emission tomography (PET) is now well established in neurodegenerative disorders, especially in the diagnosis of dementia. Measurement of cerebral glucose metabolism is of significant value, and it facilitates early diagnosis, appropriate differential diagnosis, and the evaluation of drug treatment in patients with dementia. In addition, tracers offer new perspectives for studying the neuropathology of underlying dementia, such as the accumulation of amyloid proteins, tau-proteins, or the presence of neuroinflammation. Finally, PET tracer studies of different neurotransmitter systems in dementia may not only increase the understanding of pathophysiologic mechanisms of the different disorders, but also improve diagnostic accuracy. In conclusion, PET imaging with different tracers offers reliable biomarkers in dementia, which can assist clinicians in the diagnosis of different dementing disorders, especially in the situation of overlapping phenotypes.
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Affiliation(s)
- Valentina Berti
- Department of Clinical Pathophysiology, Nuclear Medicine Unit, University of Florence, Florence, Italy.
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Cummings JL. Biomarkers in Alzheimer's disease drug development. Alzheimers Dement 2011; 7:e13-44. [PMID: 21550318 DOI: 10.1016/j.jalz.2010.06.004] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 06/01/2010] [Accepted: 06/03/2010] [Indexed: 12/27/2022]
Abstract
Developing new therapies for Alzheimer's disease (AD) is critically important to avoid the impending public health disaster imposed by this common disorder. Means must be found to prevent, delay the onset, or slow the progression of AD. These goals will be achieved by identifying disease-modifying therapies and testing them in clinical trials. Biomarkers play an increasingly important role in AD drug development. In preclinical testing, they assist in decisions to develop an agent. Biomarkers in phase I provide insights into toxic responses and drug metabolism and in Phase II proof-of-concept trials they facilitate go/no-go decisions and dose finding. Biomarkers can play a role in identifying presymptomatic patients or specific patient subgroups. They can provide evidence of target engagement before clinical changes can be expected. Brain imaging can serve as a primary outcome in Phase II trials and as a key secondary outcome in Phase III trials. Magnetic resonance imaging is currently best positioned for use in large multicenter clinical trials. Cerebrospinal fluid (CSF) measures of amyloid beta protein (Aβ), tau protein, and hyperphosphorylated tau (p-tau) protein are sensitive and specific to the diagnosis of AD and may serve as inclusion criteria and possibly as outcomes in clinical trials targeting relevant pathways. Plasma measures of Aβ are of limited diagnostic value but may provide important information as a measure of treatment response. A wide variety of measures of detectable products of cellular processes are being developed as possible biomarkers accessible in the cerebrospinal fluid and plasma or serum. Surrogate markers that can function as outcomes in pivotal trials and reliably predict clinical outcomes are needed to facilitate primary prevention trials of asymptomatic persons where clinical measures may be of limited value. Fit-for-purpose biomarkers are increasingly available to guide AD drug development decisions.
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Affiliation(s)
- Jeffrey L Cummings
- Cleveland Clinic Lou Ruvo Center for Brain Health, Cleveland Clinic Neurological Institute, Las Vegas, NV, USA.
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Ceravolo R, Brusa L, Galati S, Volterrani D, Peppe A, Siciliano G, Pierantozzi M, Moschella V, Bonuccelli U, Stanzione P, Stefani A. Low frequency stimulation of the nucleus tegmenti pedunculopontini increases cortical metabolism in Parkinsonian patients. Eur J Neurol 2010; 18:842-9. [DOI: 10.1111/j.1468-1331.2010.03254.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sonnen JA, Montine KS, Quinn JF, Breitner JCS, Montine TJ. Cerebrospinal fluid biomarkers in mild cognitive impairment and dementia. J Alzheimers Dis 2010; 19:301-9. [PMID: 20061646 DOI: 10.3233/jad-2010-1236] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Given the magnitude of the public health problem of dementia in the elderly, there is a pressing need for research, development, and timely application of biomarkers that will identify latent and prodromal illness as well as dementia. Although identification of risk factors and neuroimaging measures will remain key to these efforts, this review focuses on recent progress in the discovery, validation, and standardization of cerebrospinal fluid (CSF) biomarkers, small molecules and macromolecules whose CSF concentration can aid in diagnosis at different stages of disease as well as in assessment of disease progression and response to therapeutics. A multimodal approach that brings independent information from risk factor assessment, neuroimaging, and biomarkers may soon guide physicians in the early diagnosis and management of cognitive impairment in the elderly.
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Affiliation(s)
- Joshua A Sonnen
- Department of Pathology, Division of Neuropathology, University of Washington, Seattle, WA 98104-2420, USA.
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Stefani A, Pierantozzi M, Ceravolo R, Brusa L, Galati S, Stanzione P. Deep brain stimulation of pedunculopontine tegmental nucleus (PPTg) promotes cognitive and metabolic changes: a target-specific effect or response to a low-frequency pattern of stimulation? Clin EEG Neurosci 2010; 41:82-6. [PMID: 20521490 DOI: 10.1177/155005941004100207] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Deep brain stimulation (DBS) is a reliable treatment for advanced Parkinson's disease (PD) patients, but a possible risk of worsening cognitive functions, although modest, may postpone or halt DBS clinical indication. In a small cohort of PD patients we have pioneered the simultaneous implantation of both the subthalamic nucleus (STN) and the pedunculopontine tegmental nucleus (PPTg). Here we describe the cognitive test performance and the corresponding cortical metabolic activity, as assessed through 18-fluorodeoxyglucose (FDG)-positron emission tomography (PET), of these six PD patients tested in PPTg-ON vs- PPTg-OFF condition. PPTg-ON condition (at low frequency, 25 Hz) induced better performance in tests exploring both executive and attentive domains, which were coupled with an increased glucose utilization in prefrontal and frontal bilateral cortical areas, including both lateral (i.e., BA9) and more antero-medial cortices (BA 25-32). Moreover, during PPTg-ON, a surprising increase of FDG consumption was also observed in the left ventral striatum. These data are consistent with the hypothesis of a positive effect of 25 Hz PPTg-DBS on PD patients' cognitive profile, probably due to a facilitatory effect exerted by PPTg on both associative and limbic pathways.
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Affiliation(s)
- A Stefani
- Dept. Neuroscience, University Tor Vergata, Rome, Italy
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Jagust WJ, Landau SM, Shaw LM, Trojanowski JQ, Koeppe RA, Reiman EM, Foster NL, Petersen RC, Weiner MW, Price JC, Mathis CA. Relationships between biomarkers in aging and dementia. Neurology 2009; 73:1193-9. [PMID: 19822868 DOI: 10.1212/wnl.0b013e3181bc010c] [Citation(s) in RCA: 359] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND PET imaging using [(18)F]fluorodeoxyglucose (FDG) and [(11)C]Pittsburgh compound B (PIB) have been proposed as biomarkers of Alzheimer disease (AD), as have CSF measures of the 42 amino acid beta-amyloid protein (Abeta(1-42)) and total and phosphorylated tau (t-tau and p-tau). Relationships between biomarkers and with disease severity are incompletely understood. METHODS Ten subjects with AD, 11 control subjects, and 34 subjects with mild cognitive impairment from the Alzheimer's Disease Neuroimaging Initiative underwent clinical evaluation; CSF measurement of Abeta(1-42), t-tau, and p-tau; and PIB-PET and FDG-PET scanning. Data were analyzed using continuous regression and dichotomous outcomes with subjects classified as "positive" or "negative" for AD based on cutoffs established in patients with AD and controls from other cohorts. RESULTS Dichotomous categorization showed substantial agreement between PIB-PET and CSF Abeta(1-42) measures (91% agreement, kappa = 0.74), modest agreement between PIB-PET and p-tau (76% agreement, kappa = 0.50), and minimal agreement for other comparisons (kappa <0.3). Mini-Mental State Examination score was significantly correlated with FDG-PET but not with PIB-PET or CSF Abeta(1-42). Regression models adjusted for diagnosis showed that PIB-PET was significantly correlated with Abeta(1-42), t-tau, and p-tau(181p), whereas FDG-PET was correlated only with Abeta(1-42). CONCLUSIONS PET and CSF biomarkers of Abeta agree with one another but are not related to cognitive impairment. [(18)F]fluorodeoxyglucose-PET is modestly related to other biomarkers but is better related to cognition. Different biomarkers for Alzheimer disease provide different information from one another that is likely to be complementary.
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Affiliation(s)
- W J Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94620, USA.
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Brain perfusion SPECT correlates with CSF biomarkers in Alzheimer’s disease. Eur J Nucl Med Mol Imaging 2009; 37:589-93. [DOI: 10.1007/s00259-009-1285-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 09/13/2009] [Indexed: 10/20/2022]
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Alessandro S, Ceravolo R, Brusa L, Pierantozzi M, Costa A, Galati S, Placidi F, Romigi A, Iani C, Marzetti F, Peppe A. Non-motor functions in parkinsonian patients implanted in the pedunculopontine nucleus: focus on sleep and cognitive domains. J Neurol Sci 2009; 289:44-8. [PMID: 19765737 DOI: 10.1016/j.jns.2009.08.017] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Between 2005 and 2007, six patients affected by idiopathic Parkinson's disease (IPD) were submitted to the bilateral implantation (and subsequent deep brain stimulation - DBS) of the pedunculopontine nucleus (PPN) plus the subthalamic nucleus (STN). This review synthesizes the effects of PPN low-frequency stimulation on non-motor functions, focusing on patient sleep quality and cognitive performance. If not associated to STN-DBS, PPN-DBS promoted a modest amelioration of patient motor performance. However, during PPN-DBS, they experienced on the one hand a significant improvement in executive functions and working memory, on the other hand a beneficial change in sleep architecture. Overall, the limited sample hampers definite conclusions. Yet, although the PPN-DBS induced motor effects are quite disappointing (discouraging extended trials based upon the sole PPN implantation), the neuropsychological profile supports the contention by which in selected PD patients, with subtle cognitive deficits or vanished efficacy of previous implanted STN, PPN-DBS might still represent a reliable and compassionate option.
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Petrie EC, Cross DJ, Galasko D, Schellenberg GD, Raskind MA, Peskind ER, Minoshima S. Preclinical evidence of Alzheimer changes: convergent cerebrospinal fluid biomarker and fluorodeoxyglucose positron emission tomography findings. ACTA ACUST UNITED AC 2009; 66:632-7. [PMID: 19433663 DOI: 10.1001/archneurol.2009.59] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Alterations in cerebrospinal fluid (CSF) tau and beta-amyloid peptide 1-42 (Abeta(42)) levels and rates of cerebral glucose metabolism (CMRglu) on fluorodeoxyglucose positron emission tomography (FDG-PET) occur years before clinical symptoms of Alzheimer disease (AD) become manifest, but their relationship remains unclear. OBJECTIVE To determine whether CSF AD biomarker levels and CMRglu in healthy individuals correlate in brain structures affected early in AD. DESIGN Cohort study. SETTING Alzheimer disease research center. PARTICIPANTS Twenty individuals without dementia aged 46 to 83 years. INTERVENTIONS Lumbar CSF sampling and FDG-PET imaging of CMRglu. The CSF Abeta(42), tau, and tau phosphorylated at threonine 181 (ptau(181)) levels were measured using immunobead-based multiplex assays. MAIN OUTCOME MEASURES Correlations between CMRglu and CSF biomarker levels were analyzed via voxel-based and volume-of-interest approaches. RESULTS Voxel-based analyses demonstrated significant negative correlations between CSF tau and ptau(181) levels and CMRglu in the posterior cingulate, precuneus, and parahippocampal regions. In contrast, a limited positive correlation was found between CSF Abeta(42) levels and CMRglu in the inferior temporal cortex. Volume-of-interest analyses confirmed negative associations between CSF tau and ptau(181) levels and CMRglu in the parietal and medial parietal lobes and a positive association between CSF Abeta(42) levels and CMRglu in the parahippocampal gyrus. CONCLUSIONS In healthy individuals, higher CSF tau and ptau(181) concentrations were associated with more severe hypometabolism in several brain regions affected very early in AD, whereas lower CSF Abeta(42) concentrations were associated with hypometabolism only in the medial temporal lobe. This suggests that early tau and Abeta abnormalities may be associated with subtle synaptic changes in brain regions vulnerable to AD. A longitudinal assessment of CSF and FDG-PET biomarkers is needed to determine whether these changes predict cognitive impairment and incipient AD.
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Affiliation(s)
- Eric C Petrie
- Mail Code S-182-GRECC, Veterans Affairs Puget Sound Health Care System, 1660 S Columbian Way, Seattle, WA 98108, USA.
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Brusa L, Iani C, Ceravolo R, Galati S, Moschella V, Marzetti F, Stanzione P, Stefani A. Implantation of the nucleus tegmenti pedunculopontini in a PSP-P patient: Safe procedure, modest benefits. Mov Disord 2009; 24:2020-2. [DOI: 10.1002/mds.22706] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Arlt S, Brassen S, Jahn H, Wilke F, Eichenlaub M, Apostolova I, Wenzel F, Thiele F, Young S, Buchert R. Association between FDG uptake, CSF biomarkers and cognitive performance in patients with probable Alzheimer's disease. Eur J Nucl Med Mol Imaging 2009; 36:1090-100. [PMID: 19219430 DOI: 10.1007/s00259-009-1063-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Accepted: 12/30/2008] [Indexed: 11/24/2022]
Abstract
PURPOSE Brain imaging of FDG uptake and cerebrospinal fluid (CSF) concentration of amyloid-beta 1-42 (Abeta(1-42)) or tau proteins are promising biomarkers in the diagnosis of Alzheimer's disease (AD). There is still uncertainty regarding any association between decreased FDG uptake and alterations in CSF markers. METHODS The relationship between FDG uptake, CSF Abeta(1-42) and total tau (T-tau), as well as the Mini-Mental State Examination (MMSE) score was investigated in 34 subjects with probable AD using step-wise linear regression. FDG uptake was scaled to the pons. RESULTS Scaled FDG uptake was significantly reduced in the probable AD subjects compared to 17 controls bilaterally in the precuneus/posterior cingulate area, angular gyrus/inferior parietal cortex, inferior temporal/midtemporal cortex, midfrontal cortex, and left caudate. Voxel-based single-subject analysis of the probable AD subjects at p < 0.001 (uncorrected) revealed a total volume of significant hypometabolism ranging from 0 to 452 ml (median 70 ml). The total hypometabolic volume was negatively correlated with the MMSE score, but it was not correlated with the CSF measures. VOI-based step-wise linear regression revealed that scaled FDG uptake in the precuneus/posterior cingulate was negatively correlated with CSF Abeta(1-42). Scaled FDG uptake in the caudate was positively correlated with CSF T-tau. CONCLUSION The extent and local severity of the reduction in FDG uptake in probable AD subjects are associated with cognitive impairment. In addition, there appears to be a relationship between local FDG uptake and CSF biomarkers which differs between different brain regions.
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Affiliation(s)
- Sönke Arlt
- Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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