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Yi F, Wang J, Lin M, Li B, Han S, Wang S, Jin Y, Hu N, Chen Y, Shang X. Correspondence between white matter hyperintensities and regional grey matter volumes in Alzheimer's disease. Front Aging Neurosci 2024; 16:1429098. [PMID: 39351014 PMCID: PMC11439820 DOI: 10.3389/fnagi.2024.1429098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 08/30/2024] [Indexed: 10/04/2024] Open
Abstract
Objective White matter hyperintensities (WMH) are the most common neuroimaging manifestation of cerebral small vessel disease, and is frequently observed in Alzheimer's disease (AD). This study aimed to investigate the relationship between WMH and cognition and to verify the mediation of grey matter atrophy in this relationship. Methods The diffusion tensor imaging (DTI) technique analyses white matter fiber tract to assess white matter integrity. Voxel-based morphometry was applied to measure the grey matter volume (GMV). A linear regression model was applied to examine the associations between WMH and GMV, and mediation analyses was performed to determine the mediating role of regional GMV in the effect of WMH on cognitive function. Results Compared to the HC group, AD group have 8 fiber tract fractional anisotropy (FA) decreased and 16 fiber tract mean diffusivity (MD) increased. Compared to AD without WMH, AD with high WMH had 9 fiber tracts FA decreased and 13 fiber tracts MD increased. High WMH volume was negatively correlated with GMV in the frontal-parietal region. Low WMH volume was also negatively correlated with GMV except for the three regions (right angular gyrus, right superior frontal gyrus and right middle/inferior parietal gyrus), where GMV was positively correlated. Mediation analysis showed that the association between WMH and executive function or episodic memory were mediated by GMV in the frontal-parietal region. Conclusion Damage to white matter integrity was more severe in AD with WMH. Differential changes in DTI metrics may be caused by progressive myelin and axonal damage. There was a negative correlation between WMH and grey matter atrophy in frontal-parietal regions in a volume-dependent manner. This study indicates the correspondence between WMH volume and GMV in cognition, and GMV being a key modulator between WMH and cognition in AD. This result will contribute to understanding the progression of the disease process and applying targeted therapeutic intervention in the earlier stage to delay neurodegenerative changes in frontal-parietal regions to achieve better treatment outcomes and affordability.
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Affiliation(s)
- Fangyuan Yi
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
- Department of Neurology, Jin Qiu Hospital of Liaoning Province (Geriatric Hospital of Liaoning Province), Shenyang, China
| | - Jirui Wang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Meiqing Lin
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Baizhu Li
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Shiyu Han
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Shan Wang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Yingbin Jin
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Ning Hu
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Yutong Chen
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Xiuli Shang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
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Mu R, Qin X, Zheng W, Yang P, Huang B, Li X, Liu F, Deng K, Zhu X. Amide proton transfer could be a surrogate imaging marker for predicting vascular cognitive impairment. Brain Res Bull 2023; 204:110793. [PMID: 37863439 DOI: 10.1016/j.brainresbull.2023.110793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/27/2023] [Accepted: 10/17/2023] [Indexed: 10/22/2023]
Abstract
BACKGROUD Emerging evidence suggests an overlap in the underlying pathways contributing to both cerebral small vessel disease (CSVD) and the neurodegenerative disease. Studies investigating the progression of CSVD should incorporate markers that reflect neurodegenerative lesions. OBJECTIVE We aim to investigate whether Amide proton transfer (APT) can serve as a potential marker for reflecting vascular cognitive impairment (VCI). METHOD Participants were categorized into one of three groups based on their Montreal Cognitive Assessment (MoCA) scores: normal control group (age,54.9 ± 7.9; male, 52.9%), mild cognitive impairment (MCI) group (age,55.7 ± 6.9; male, 42.6%), or vascular dementia (VaD) group (age,57.6 ± 5.5, male, 58.5%). One way analysis of variance was performed to compare the demographic and APT variables between groups. Multiple logistic regression analysis wwas constructed to examine the relationship between APT values and VCI grouping. A hierarchical linear regression model was employed to examine the associations between patients' demographic factors, imaging markers, APT values, and MoCA. RESULTS The APT values of frontal white matter, hippocampus, amygdala, and thalamus were significantly different among different groups (p < 0.05). The APT values of frontal white matter, amygdala, and thalamus indicate a significant positive effect on MCI grouping. the APT values of frontal white matter, amygdala, and thalamus indicate a significant positive effect on VaD grouping. The demographic data, CSVD imaging markers and APT values can account for 5.1%, 20.1% and 27.7% of the variation in MoCA, respectively. CONCLUSION APT imaging can partially identifying and predicting the occurrence of VCI.
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Affiliation(s)
- Ronghua Mu
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China
| | - Xiaoyan Qin
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China
| | - Wei Zheng
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China
| | - Peng Yang
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China
| | - Bingqin Huang
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China; Graduate School, Guilin Medical University, 541002 Guilin, China
| | - Xin Li
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China
| | - Fuzhen Liu
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China
| | - Kan Deng
- Philips (China) Investment Co., Ltd., Guangzhou Branch, 510000 Guangzhou, China
| | - Xiqi Zhu
- Department of Radiology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, 541004 Guilin, China.
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Pansieri J, Hadley G, Lockhart A, Pisa M, DeLuca GC. Regional contribution of vascular dysfunction in white matter dementia: clinical and neuropathological insights. Front Neurol 2023; 14:1199491. [PMID: 37396778 PMCID: PMC10313211 DOI: 10.3389/fneur.2023.1199491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/25/2023] [Indexed: 07/04/2023] Open
Abstract
The maintenance of adequate blood supply and vascular integrity is fundamental to ensure cerebral function. A wide range of studies report vascular dysfunction in white matter dementias, a group of cerebral disorders characterized by substantial white matter damage in the brain leading to cognitive impairment. Despite recent advances in imaging, the contribution of vascular-specific regional alterations in white matter dementia has been not extensively reviewed. First, we present an overview of the main components of the vascular system involved in the maintenance of brain function, modulation of cerebral blood flow and integrity of the blood-brain barrier in the healthy brain and during aging. Second, we review the regional contribution of cerebral blood flow and blood-brain barrier disturbances in the pathogenesis of three distinct conditions: the archetypal white matter predominant neurocognitive dementia that is vascular dementia, a neuroinflammatory predominant disease (multiple sclerosis) and a neurodegenerative predominant disease (Alzheimer's). Finally, we then examine the shared landscape of vascular dysfunction in white matter dementia. By emphasizing the involvement of vascular dysfunction in the white matter, we put forward a hypothetical map of vascular dysfunction during disease-specific progression to guide future research aimed to improve diagnostics and facilitate the development of tailored therapies.
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de la Monte SM. Malignant Brain Aging: The Formidable Link Between Dysregulated Signaling Through Mechanistic Target of Rapamycin Pathways and Alzheimer's Disease (Type 3 Diabetes). J Alzheimers Dis 2023; 95:1301-1337. [PMID: 37718817 PMCID: PMC10896181 DOI: 10.3233/jad-230555] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
Malignant brain aging corresponds to accelerated age-related declines in brain functions eventually derailing the self-sustaining forces that govern independent vitality. Malignant brain aging establishes the path toward dementing neurodegeneration, including Alzheimer's disease (AD). The full spectrum of AD includes progressive dysfunction of neurons, oligodendrocytes, astrocytes, microglia, and the microvascular systems, and is mechanistically driven by insulin and insulin-like growth factor (IGF) deficiencies and resistances with accompanying deficits in energy balance, increased cellular stress, inflammation, and impaired perfusion, mimicking the core features of diabetes mellitus. The underlying pathophysiological derangements result in mitochondrial dysfunction, abnormal protein aggregation, increased oxidative and endoplasmic reticulum stress, aberrant autophagy, and abnormal post-translational modification of proteins, all of which are signature features of both AD and dysregulated insulin/IGF-1-mechanistic target of rapamycin (mTOR) signaling. This article connects the dots from benign to malignant aging to neurodegeneration by reviewing the salient pathologies associated with initially adaptive and later dysfunctional mTOR signaling in the brain. Effective therapeutic and preventive measures must be two-pronged and designed to 1) address complex and shifting impairments in mTOR signaling through the re-purpose of effective anti-diabetes therapeutics that target the brain, and 2) minimize the impact of extrinsic mediators of benign to malignant aging transitions, e.g., inflammatory states, obesity, systemic insulin resistance diseases, and repeated bouts of general anesthesia, by minimizing exposures or implementing neuroprotective measures.
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Affiliation(s)
- Suzanne M. de la Monte
- Departments of Pathology and Laboratory Medicine, Medicine, Neurology and Neurosurgery, Rhode Island Hospital, Lifespan Academic Institutions, and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Lim SH, Lee J, Jung S, Kim B, Rhee HY, Oh SH, Park S, Cho AR, Ryu CW, Jahng GH. Myelin-Weighted Imaging Presents Reduced Apparent Myelin Water in Patients with Alzheimer’s Disease. Diagnostics (Basel) 2022; 12:diagnostics12020446. [PMID: 35204537 PMCID: PMC8871299 DOI: 10.3390/diagnostics12020446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/27/2022] [Accepted: 02/06/2022] [Indexed: 02/04/2023] Open
Abstract
The purpose of this study was to investigate myelin loss in both AD and mild cognitive impairment (MCI) patients with a new myelin water mapping technique within reasonable scan time and evaluate the clinical relevance of the apparent myelin water fraction (MWF) values by assessing the relationship between decreases in myelin water and the degree of memory decline or aging. Twenty-nine individuals were assigned to the cognitively normal (CN) elderly group, 32 participants were assigned to the MCI group, and 31 patients were assigned to the AD group. A 3D visualization of the short transverse relaxation time component (ViSTa)-gradient and spin-echo (GraSE) sequence was developed to map apparent MWF. Then, the MWF values were compared between the three participant groups and was evaluated the relationship with the degree of memory loss. The AD group showed a reduced apparent MWF compared to the CN and MCI groups. The largest AUC (area under the curve) value was in the corpus callosum and used to classify the CN and AD groups using the apparent MWF. The ViSTa-GraSE sequence can be a useful tool to map the MWF in a reasonable scan time. Combining the MWF in the corpus callosum with the detection of atrophy in the hippocampus can be valuable for group classification.
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Affiliation(s)
- Seung-Hyun Lim
- Department of Radiology, Kyung Hee University Hospital at Gangdong, 892 Dongnam-ro, Gangdong-gu, Seoul 05278, Korea; (S.-H.L.); (B.K.); (C.-W.R.)
| | - Jiyoon Lee
- Department of Biomedical Engineering, Undergraduate School, College of Electronics and Information, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea; (J.L.); (S.J.)
| | - Sumin Jung
- Department of Biomedical Engineering, Undergraduate School, College of Electronics and Information, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea; (J.L.); (S.J.)
| | - Bokyung Kim
- Department of Radiology, Kyung Hee University Hospital at Gangdong, 892 Dongnam-ro, Gangdong-gu, Seoul 05278, Korea; (S.-H.L.); (B.K.); (C.-W.R.)
| | - Hak Young Rhee
- Department of Neurology, Kyung Hee University Hospital at Gangdong, 892 Dongnam-ro, Gangdong-gu, Seoul 05278, Korea;
- Department of Medicine, College of Medicine, Kyung Hee University, 26 Kyung Hee Dae-ro, Dongdaemun-gu, Seoul 02447, Korea; (S.P.); (A.R.C.)
| | - Se-Hong Oh
- Division of Biomedical Engineering, Hankuk University of Foreign Studies, Yongin 17035, Korea;
| | - Soonchan Park
- Department of Medicine, College of Medicine, Kyung Hee University, 26 Kyung Hee Dae-ro, Dongdaemun-gu, Seoul 02447, Korea; (S.P.); (A.R.C.)
| | - Ah Rang Cho
- Department of Medicine, College of Medicine, Kyung Hee University, 26 Kyung Hee Dae-ro, Dongdaemun-gu, Seoul 02447, Korea; (S.P.); (A.R.C.)
- Department of Psychiatry, Kyung Hee University Hospital at Gangdong, 892 Dongnam-ro, Gangdong-gu, Seoul 05278, Korea
| | - Chang-Woo Ryu
- Department of Radiology, Kyung Hee University Hospital at Gangdong, 892 Dongnam-ro, Gangdong-gu, Seoul 05278, Korea; (S.-H.L.); (B.K.); (C.-W.R.)
- Department of Medicine, College of Medicine, Kyung Hee University, 26 Kyung Hee Dae-ro, Dongdaemun-gu, Seoul 02447, Korea; (S.P.); (A.R.C.)
| | - Geon-Ho Jahng
- Department of Radiology, Kyung Hee University Hospital at Gangdong, 892 Dongnam-ro, Gangdong-gu, Seoul 05278, Korea; (S.-H.L.); (B.K.); (C.-W.R.)
- Department of Medicine, College of Medicine, Kyung Hee University, 26 Kyung Hee Dae-ro, Dongdaemun-gu, Seoul 02447, Korea; (S.P.); (A.R.C.)
- Correspondence: ; Tel.: +82-2-440-6187; Fax: +82-2-440-6932
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Wang J, Wang P, Jiang Y, Wang Z, Zhang H, Li H, Biswal BB. Hippocampus-Based Dynamic Functional Connectivity Mapping in the Early Stages of Alzheimer's Disease. J Alzheimers Dis 2021; 85:1795-1806. [PMID: 34958033 DOI: 10.3233/jad-215239] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The hippocampus with varying degrees of atrophy was a crucial neuroimaging feature resulting in the declining memory and cognitive function in Alzheimer's disease (AD). However, the abnormal dynamic functional connectivity (DFC) in both white matter (WM) and gray matter (GM) from the left and right hippocampus remains unclear. OBJECTIVE To explore the abnormal DFC within WM and GM from the left and right hippocampus across the different stages of AD. METHODS Current study employed the OASIS-3 dataset including 43 mild cognitive impairment (MCI), 71 pre-mild cognitive impairment (pre-MCI), and matched 87 normal cognitive (NC). Adopting the FMRIB's Integrated Registration and Segmentation Tool, we obtained the left and right hippocampus mask. Based on above hippocampus mask as seed point, we calculated the DFC between left/right hippocampus and all voxel time series within whole brain. One-way ANOVA analysis was performed to estimate the abnormal DFC among MCI, pre-MCI, and NC groups. RESULTS We found that MCI and pre-MCI groups showed the common abnormalities of DFC in the Temporal_Mid_L, Cingulum_Mid_L, and Thalamus_L. Specific abnormalities were found in the Cerebelum_9_L and Precuneus of MCI group and Vermis_8 and Caudate_L of pre-MCI group. In addition, we found that DFC within WM regions also showed the common low DFC for the Cerebellum anterior lobe-WM, Corpus callosum, and Frontal lobe-WM in MCI and pre-MCI group. CONCLUSION Our findings provided a novel information for discover the pathophysiological mechanisms of AD and indicate WM lesions were also an important cause of cognitive decline in AD.
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Affiliation(s)
- Jianlin Wang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Pan Wang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Yuan Jiang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Zedong Wang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Hong Zhang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Hongyi Li
- The Fourth People's Hospital of Chengdu, Chengdu, China
| | - Bharat B Biswal
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.,Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA
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Ramírez-Toraño F, Abbas K, Bruña R, Marcos de Pedro S, Gómez-Ruiz N, Barabash A, Pereda E, Marcos A, López-Higes R, Maestu F, Goñi J. A Structural Connectivity Disruption One Decade before the Typical Age for Dementia: A Study in Healthy Subjects with Family History of Alzheimer's Disease. Cereb Cortex Commun 2021; 2:tgab051. [PMID: 34647029 PMCID: PMC8501268 DOI: 10.1093/texcom/tgab051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 11/23/2022] Open
Abstract
The concept of the brain has shifted to a complex system where different subnetworks support the human cognitive functions. Neurodegenerative diseases would affect the interactions among these subnetworks and, the evolution of impairment and the subnetworks involved would be unique for each neurodegenerative disease. In this study, we seek for structural connectivity traits associated with the family history of Alzheimer's disease, that is, early signs of subnetworks impairment due to Alzheimer's disease. The sample in this study consisted of 123 first-degree Alzheimer's disease relatives and 61 nonrelatives. For each subject, structural connectomes were obtained using classical diffusion tensor imaging measures and different resolutions of cortical parcellation. For the whole sample, independent structural-connectome-traits were obtained under the framework of connICA. Finally, we tested the association of the structural-connectome-traits with different factors of relevance for Alzheimer's disease by means of a multiple linear regression. The analysis revealed a structural-connectome-trait obtained from fractional anisotropy associated with the family history of Alzheimer's disease. The structural-connectome-trait presents a reduced fractional anisotropy pattern in first-degree relatives in the tracts connecting posterior areas and temporal areas. The family history of Alzheimer's disease structural-connectome-trait presents a posterior-posterior and posterior-temporal pattern, supplying new evidences to the cascading network failure model.
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Affiliation(s)
- F Ramírez-Toraño
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Department of Experimental Psychology, Universidad Complutense de Madrid, Madrid 28223, Comunidad de Madrid, Spain
| | - Kausar Abbas
- Purdue Institute for Integrative Neuroscience, Purdue University, West-Lafayette, IN 46202, USA
- School of Industrial Engineering, Purdue University, West Lafayette, IN 46202, USA
| | - Ricardo Bruña
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Department of Experimental Psychology, Universidad Complutense de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN), Madrid 28029, Comunidad de Madrid, Spain
| | - Silvia Marcos de Pedro
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Facultad de Educación y Salud, Universidad Camilo José Cela, Madrid 28010, Comunidad de Madrid, Spain
| | - Natividad Gómez-Ruiz
- Sección Neurorradiología, Servicio de Diagnóstico por Imagen, Hospital Clínico San Carlos, Madrid 28040, Comunidad de Madrid, Spain
| | - Ana Barabash
- Endocrinology and Nutrition Department, Hospital Clinico San Carlos and Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid 28040, Comunidad de Madrid, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid 28029, Comunidad de Madrid, Spain
| | - Ernesto Pereda
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Electrical Engineering and Bioengineering Group, Department of Industrial Engineering & IUNE & ITB, Universidad de La Laguna, Santa Cruz de Tenerife 38205, Spain
| | - Alberto Marcos
- Neurology Department, Hospital Clinico San Carlos and Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid 28040, Comunidad de Madrid, Spain
| | - Ramón López-Higes
- Department of Experimental Psychology, Universidad Complutense de Madrid, Madrid 28223, Comunidad de Madrid, Spain
| | - Fernando Maestu
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Department of Experimental Psychology, Universidad Complutense de Madrid, Madrid 28223, Comunidad de Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN), Madrid 28029, Comunidad de Madrid, Spain
| | - Joaquín Goñi
- Purdue Institute for Integrative Neuroscience, Purdue University, West-Lafayette, IN 46202, USA
- School of Industrial Engineering, Purdue University, West Lafayette, IN 46202, USA
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 46202, USA
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Kochunov P, Zavaliangos-Petropulu A, Jahanshad N, Thompson PM, Ryan MC, Chiappelli J, Chen S, Du X, Hatch K, Adhikari B, Sampath H, Hare S, Kvarta M, Goldwaser E, Yang F, Olvera RL, Fox PT, Curran JE, Blangero J, Glahn DC, Tan Y, Hong LE. A White Matter Connection of Schizophrenia and Alzheimer's Disease. Schizophr Bull 2021; 47:197-206. [PMID: 32681179 PMCID: PMC7825012 DOI: 10.1093/schbul/sbaa078] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Schizophrenia (SZ) is a severe psychiatric illness associated with an elevated risk for developing Alzheimer's disease (AD). Both SZ and AD have white matter abnormalities and cognitive deficits as core disease features. We hypothesized that aging in SZ patients may be associated with the development of cerebral white matter deficit patterns similar to those observed in AD. We identified and replicated aging-related increases in the similarity between white matter deficit patterns in patients with SZ and AD. The white matter "regional vulnerability index" (RVI) for AD was significantly higher in SZ patients compared with healthy controls in both the independent discovery (Cohen's d = 0.44, P = 1·10-5, N = 173 patients/230 control) and replication (Cohen's d = 0.78, P = 9·10-7, N = 122 patients/64 controls) samples. The degree of overlap with the AD deficit pattern was significantly correlated with age in patients (r = .21 and .29, P < .01 in discovery and replication cohorts, respectively) but not in controls. Elevated RVI-AD was significantly associated with cognitive measures in both SZ and AD. Disease and cognitive specificities were also tested in patients with mild cognitive impairment and showed intermediate overlap. SZ and AD have diverse etiologies and clinical courses; our findings suggest that white matter deficits may represent a key intersecting point for these 2 otherwise distinct diseases. Identifying mechanisms underlying this white matter deficit pattern may yield preventative and treatment targets for cognitive deficits in both SZ and AD patients.
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Affiliation(s)
- Peter Kochunov
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Artemis Zavaliangos-Petropulu
- Imaging Genetics Center, Mark & Mary Stevens Neuroimaging & Informatics Institute, Keck School of Medicine, University of Southern California of USC, Marina del Rey, CA
| | - Neda Jahanshad
- Imaging Genetics Center, Mark & Mary Stevens Neuroimaging & Informatics Institute, Keck School of Medicine, University of Southern California of USC, Marina del Rey, CA
| | - Paul M Thompson
- Imaging Genetics Center, Mark & Mary Stevens Neuroimaging & Informatics Institute, Keck School of Medicine, University of Southern California of USC, Marina del Rey, CA
| | - Meghann C Ryan
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Joshua Chiappelli
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Shuo Chen
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Xiaoming Du
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Kathryn Hatch
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Bhim Adhikari
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Hemalatha Sampath
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Stephanie Hare
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Mark Kvarta
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Eric Goldwaser
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Fude Yang
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Rene L Olvera
- Department of Psychiatry, University of Texas Health Science Center at San Antonio, San Antonio, TX
| | - Peter T Fox
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX
| | - Joanne E Curran
- Department of Human Genetics and South Texas Diabetes and Obesity Institute, School of Medicine, University of Texas Rio Grande Valley, Brownsville, TX
| | - John Blangero
- Department of Human Genetics and South Texas Diabetes and Obesity Institute, School of Medicine, University of Texas Rio Grande Valley, Brownsville, TX
| | - David C Glahn
- Department of Psychiatry, Boston Children’s Hospital, Harvard Medical School, Boston, MA
| | - Yunlong Tan
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - L Elliot Hong
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
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Skoog I, Kern S, Zetterberg H, Östling S, Börjesson-Hanson A, Guo X, Blennow K. Low Cerebrospinal Fluid Aβ42 and Aβ40 are Related to White Matter Lesions in Cognitively Normal Elderly. J Alzheimers Dis 2019; 62:1877-1886. [PMID: 29614655 PMCID: PMC5900552 DOI: 10.3233/jad-170950] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Background: Low cerebrospinal fluid (CSF) levels of Aβ42 may be the earliest manifestation of Alzheimer’s disease (AD). Knowledge on how CSF Aβ interacts with different brain pathologies early in the disease process is limited. We examined how CSF Aβ markers relate to brain atrophy and white matter lesions (WMLs) in octogenarians with and without dementia to explore the earliest pathogenetic pathways of AD in the oldest old. Objective: To study CSF amyloid biomarkers in relation to brain atrophy and WMLs in 85-year-olds with and without dementia. Methods: 53 octogenarians took part in neuropsychiatric examinations and underwent both a lumbar puncture and a brain CT scan. CSF levels of Aβ42 and Aβ40 were examined in relation to cerebral atrophy and WMLs. Dementia was diagnosed. Results: In 85-year-olds without dementia, lower levels of both CSF Aβ42 and CSF Aβ40 were associated with WMLs. CSF Aβ42 also correlated with measures of central atrophy, but not with cortical atrophy. In participants with dementia, lower CSF levels of Aβ42 were related to frontal, temporal, and parietal cortical atrophy but not to WMLs. Conclusions: Our findings may suggest that there is an interrelationship between Aβ and subcortical WMLs in older persons without dementia. After onset of dementia, low CSF Aβ42, probably representing amyloid deposition in plaques, is associated with cortical atrophy. WMLs may be an earlier manifestation of Aβ deposition than cortical degeneration.
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Affiliation(s)
- Ingmar Skoog
- Department of Psychiatry and Neurochemistry, Neuropsychiatric Epidemiology Unit, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Silke Kern
- Department of Psychiatry and Neurochemistry, Neuropsychiatric Epidemiology Unit, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,Department of Psychiatry and Neurochemistry, Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,UCL Institute of Neurology, Queen Square, London, UK
| | - Svante Östling
- Department of Psychiatry and Neurochemistry, Neuropsychiatric Epidemiology Unit, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Anne Börjesson-Hanson
- Department of Psychiatry and Neurochemistry, Neuropsychiatric Epidemiology Unit, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Xinxin Guo
- Department of Psychiatry and Neurochemistry, Neuropsychiatric Epidemiology Unit, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
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10
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Mao L, Yang T, Li X, Lei X, Sun Y, Zhao Y, Zhang W, Gao Y, Sun B, Zhang F. Protective effects of sulforaphane in experimental vascular cognitive impairment: Contribution of the Nrf2 pathway. J Cereb Blood Flow Metab 2019; 39. [PMID: 29533123 PMCID: PMC6365596 DOI: 10.1177/0271678x18764083] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The major pathophysiological process of vascular cognitive impairment (VCI) is chronic cerebral ischemia, which causes disintegration of the blood-brain barrier (BBB), neuronal death, and white matter injury. This study aims to test whether sulforaphane (Sfn), a natural activator of nuclear factor erythroid 2-related factor 2 (Nrf2), reduces the chronic ischemic injury and cognitive dysfunction after VCI. Experimental VCI was induced in rats by permanent occlusion of both common carotid arteries for six weeks. This procedure caused notable neuronal death in the cortex and hippocampal CA1, myelin loss in the corpus callosum and hippocampal fimbria, accumulation of myelin debris in the corpus callosum, and remarkable cognitive impairment. Sfn treatment alleviated these ischemic injuries and the cognitive dysfunction. Sfn-mediated neuroprotection was associated with enhanced activation of Nrf2 and upregulation of heme oxygenase 1. Sfn also reduced neuronal and endothelial death and maintained the integrity of BBB after oxygen-glucose deprivation in vitro in an Nrf2 dependent manner. Furthermore, Nrf2 knockdown in endothelial cells decreased claudin-5 protein expression with downregulated claudin-5 promoter activity, suggesting that claudin-5 might be a target gene of Nrf2. Our results demonstrate that Sfn provides robust neuroprotection against chronic brain ischemic injury and may be a promising agent for VCI treatment.
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Affiliation(s)
- Leilei Mao
- 1 Department of Neurology, School of Medicine, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh, Pittsburgh, PA, USA.,2 Key Laboratory of Cerebral Microcirculation, Taishan Medical University, Tai'an, Shandong, China
| | - Tuo Yang
- 1 Department of Neurology, School of Medicine, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Xin Li
- 2 Key Laboratory of Cerebral Microcirculation, Taishan Medical University, Tai'an, Shandong, China
| | - Xia Lei
- 2 Key Laboratory of Cerebral Microcirculation, Taishan Medical University, Tai'an, Shandong, China
| | - Yang Sun
- 1 Department of Neurology, School of Medicine, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yongfang Zhao
- 3 State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China
| | - Wenting Zhang
- 3 State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China
| | - Yanqin Gao
- 1 Department of Neurology, School of Medicine, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh, Pittsburgh, PA, USA.,3 State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China
| | - Baoliang Sun
- 2 Key Laboratory of Cerebral Microcirculation, Taishan Medical University, Tai'an, Shandong, China
| | - Feng Zhang
- 1 Department of Neurology, School of Medicine, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh, Pittsburgh, PA, USA.,2 Key Laboratory of Cerebral Microcirculation, Taishan Medical University, Tai'an, Shandong, China
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11
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de la Monte SM. The Full Spectrum of Alzheimer's Disease Is Rooted in Metabolic Derangements That Drive Type 3 Diabetes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1128:45-83. [PMID: 31062325 PMCID: PMC9996398 DOI: 10.1007/978-981-13-3540-2_4] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The standard practice in neuropathology is to diagnose Alzheimer's disease (AD) based on the distribution and abundance of neurofibrillary tangles and Aβ deposits. However, other significant abnormalities including neuroinflammation, gliosis, white matter degeneration, non-Aβ microvascular disease, and insulin-related metabolic dysfunction require further study to understand how they could be targeted to more effectively remediate AD. This review addresses non-Aβ and non-pTau AD-associated pathologies, highlighting their major features, roles in neurodegeneration, and etiopathic links to deficits in brain insulin and insulin-like growth factor signaling and cognitive impairment. The discussion delineates why AD with its most characteristic clinical and pathological phenotypic profiles should be regarded as a brain form of diabetes, i.e., type 3 diabetes, and entertains the hypothesis that type 3 diabetes is just one of the categories of insulin resistance diseases that can occur independently or overlap with one or more of the others, including type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease.
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Affiliation(s)
- Suzanne M de la Monte
- Departments of Neurology, Neuropathology, and Neurosurgery, Rhode Island Hospital, and the Alpert Medical School of Brown University, Providence, RI, USA.
- Department of Pathology and Laboratory Medicine, Providence VA Medical Center, Providence, RI, USA.
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12
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Dong YX, Zhang HY, Li HY, Liu PH, Sui Y, Sun XH. Association between Alzheimer's disease pathogenesis and early demyelination and oligodendrocyte dysfunction. Neural Regen Res 2018; 13:908-914. [PMID: 29863022 PMCID: PMC5998637 DOI: 10.4103/1673-5374.232486] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The APPSwe/PSEN1dE9 (APP/PS1) transgenic mouse model is an Alzheimer's disease mouse model exhibiting symptoms of dementia, and is commonly used to explore pathological changes in the development of Alzheimer's disease. Previous clinical autopsy and imaging studies suggest that Alzheimer's disease patients have white matter and oligodendrocyte damage, but the underlying mechanisms of these have not been revealed. Therefore, the present study used APP/PS1 mice to assess cognitive change, myelin loss, and corresponding changes in oligodendrocytes, and to explore the underlying mechanisms. Morris water maze tests were performed to evaluate cognitive change in APP/PS1 mice and normal C57BL/6 mice aged 3 and 6 months. Luxol fast blue staining of the corpus callosum and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for myelin basic protein (MBP) mRNA were carried out to quantify myelin damage. Immunohistochemistry staining for NG2 and qRT-PCR for monocarboxylic acid transporter 1 (MCT1) mRNA were conducted to assess corresponding changes in oligodendrocytes. Our results demonstrate that compared with C57BL/6 mice, there was a downregulation of MBP mRNA in APP/PS1 mice aged 3 months. This became more obvious in APP/PS1 mice aged 6 months accompanied by other abnormalities such as prolonged escape latency in the Morris water maze test, shrinkage of the corpus callosum, upregulation of NG2-immunoreactive cells, and downregulation of MCT1 mRNA. These findings indicate that the involvement of early demyelination at 3 months and the oligodendrocyte dysfunction at 6 months in APP/PS1 mice are in association with Alzheimer's disease pathogenesis.
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Affiliation(s)
- Yu-Xia Dong
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang; Department of Neurology, Fushun Second Hospital, Fushun, Liaoning Province, China
| | - Hui-Yu Zhang
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
| | - Hui-Yuan Li
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
| | - Pei-Hui Liu
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang; Department of Neurology, Huludao Central Hospital, Huludao, Liaoning Province, China
| | - Yi Sui
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University; Department of Neurology, Shenyang First People's Hospital, Shenyang, Liaoning Province, China
| | - Xiao-Hong Sun
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
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13
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Cavedo E, Lista S, Rojkova K, Chiesa PA, Houot M, Brueggen K, Blautzik J, Bokde ALW, Dubois B, Barkhof F, Pouwels PJW, Teipel S, Hampel H. Disrupted white matter structural networks in healthy older adult APOE ε4 carriers - An international multicenter DTI study. Neuroscience 2017; 357:119-133. [PMID: 28596117 DOI: 10.1016/j.neuroscience.2017.05.048] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 05/24/2017] [Accepted: 05/29/2017] [Indexed: 12/20/2022]
Abstract
The ε4 allelic variant of the Apolipoprotein E gene (APOE ε4) is the best-established genetic risk factor for late-onset Alzheimer's disease (AD). White matter (WM) microstructural damages measured with Diffusion Tensor Imaging (DTI) represent an early sign of fiber tract disconnection in AD. We examined the impact of APOE ε4 on WM microstructure in elderly individuals from the multicenter European DTI Study on Dementia. Voxelwise statistical analysis of fractional anisotropy (FA), mean diffusivity, radial and axial diffusivity (MD, radD and axD respectively) was carried out using Tract-Based Spatial Statistics. Seventy-four healthy elderly individuals - 31 APOE ε4 carriers (APOE ε4+) and 43 APOE ε4 non-carriers (APOE ε4-) -were considered for data analysis. All the results were corrected for scanner acquisition protocols, age, gender and for multiple comparisons. APOE ε4+ and APOE ε4- subjects were comparable regarding sociodemographic features and global cognition. A significant reduction of FA and increased radD was found in the APOE ε4+ compared to the APOE ε4- in the cingulum, in the corpus callosum, in the inferior fronto-occipital and in the inferior longitudinal fasciculi, internal and external capsule. APOE ε4+, compared to APOE ε4- showed higher MD in the genu, right internal capsule, superior longitudinal fasciculus and corona radiate. Comparisons stratified by center supported the results obtained on the whole sample. These findings support previous evidence in monocentric studies indicating a modulatory role of APOE ɛ4 allele on WM microstructure in elderly individuals at risk for AD suggesting early vulnerability and/or reduced resilience of WM tracts involved in AD.
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Affiliation(s)
- Enrica Cavedo
- AXA Research Fund & UPMC Chair, Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Paris 06, Inserm, CNRS, Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital Pitié-Salpêtrière, Boulevard de l'hôpital, F-75013 Paris, France; Laboratory of Alzheimer's Neuroimaging and Epidemiology, IRCCS Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.
| | - Simone Lista
- AXA Research Fund & UPMC Chair, Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Paris 06, Inserm, CNRS, Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital Pitié-Salpêtrière, Boulevard de l'hôpital, F-75013 Paris, France
| | - Katrine Rojkova
- AXA Research Fund & UPMC Chair, Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Paris 06, Inserm, CNRS, Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital Pitié-Salpêtrière, Boulevard de l'hôpital, F-75013 Paris, France
| | - Patrizia A Chiesa
- AXA Research Fund & UPMC Chair, Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Paris 06, Inserm, CNRS, Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital Pitié-Salpêtrière, Boulevard de l'hôpital, F-75013 Paris, France
| | - Marion Houot
- Institute of Memory and Alzheimer's Disease (IM2A), Centre of Excellence of Neurodegenerative Disease (CoEN), ICM, APHP Department of Neurology, Hopital Pitié-Salpêtrière, University Paris 6, Paris, France
| | | | - Janusch Blautzik
- Institute for Clinical Radiology, Department of MRI, Ludwig Maximilian University Munich, Germany
| | - Arun L W Bokde
- Cognitive Systems Group, Discipline of Psychiatry, School of Medicine, Trinity College Dublin, Dublin, Ireland; and Trinity College Institute of Neuroscience (TCIN), Trinity College Dublin, Dublin, Ireland
| | - Bruno Dubois
- Sorbonne Universities, Pierre et Marie Curie University, Paris 06, Institute of Memory and Alzheimer's Disease (IM2A) & Brain and Spine Institute (ICM) UMR S 1127, Departament of Neurology, Hopital Pitié-Salpêtrière, Paris, France
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, VU University Medical Centre, The Netherlands
| | - Petra J W Pouwels
- Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, VU University Medical Centre, The Netherlands
| | - Stefan Teipel
- DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany; Department of Psychosomatic Medicine, University Medicine Rostock, Rostock, Germany
| | - Harald Hampel
- AXA Research Fund & UPMC Chair, Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Paris 06, Inserm, CNRS, Institut du Cerveau et de la Moelle Épinière (ICM), Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital Pitié-Salpêtrière, Boulevard de l'hôpital, F-75013 Paris, France.
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14
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Love S, Miners JS. Cerebrovascular disease in ageing and Alzheimer's disease. Acta Neuropathol 2016; 131:645-58. [PMID: 26711459 PMCID: PMC4835514 DOI: 10.1007/s00401-015-1522-0] [Citation(s) in RCA: 200] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 12/03/2015] [Accepted: 12/07/2015] [Indexed: 12/14/2022]
Abstract
Cerebrovascular disease (CVD) and Alzheimer’s disease (AD) have more in common than their association with ageing. They share risk factors and overlap neuropathologically. Most patients with AD have Aβ amyloid angiopathy and degenerative changes affecting capillaries, and many have ischaemic parenchymal abnormalities. Structural vascular disease contributes to the ischaemic abnormalities in some patients with AD. However, the stereotyped progression of hypoperfusion in this disease, affecting first the precuneus and cingulate gyrus, then the frontal and temporal cortex and lastly the occipital cortex, suggests that other factors are more important, particularly in early disease. Whilst demand for oxygen and glucose falls in late disease, functional MRI, near infrared spectroscopy to measure the saturation of haemoglobin by oxygen, and biochemical analysis of myelin proteins with differential susceptibility to reduced oxygenation have all shown that the reduction in blood flow in AD is primarily a problem of inadequate blood supply, not reduced metabolic demand. Increasing evidence points to non-structural vascular dysfunction rather than structural abnormalities of vessel walls as the main cause of cerebral hypoperfusion in AD. Several mediators are probably responsible. One that is emerging as a major contributor is the vasoconstrictor endothelin-1 (EDN1). Whilst there is clearly an additive component to the clinical and pathological effects of hypoperfusion and AD, experimental and clinical observations suggest that the disease processes also interact mechanistically at a cellular level in a manner that exacerbates both. The elucidation of some of the mechanisms responsible for hypoperfusion in AD and for the interactions between CVD and AD has led to the identification of several novel therapeutic approaches that have the potential to ameliorate ischaemic damage and slow the progression of neurodegenerative disease.
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Affiliation(s)
- Seth Love
- Institute of Clinical Neurosciences, School of Clinical Sciences, Learning and Research Level 2, Southmead Hospital, University of Bristol, Bristol, BS10 5NB, UK.
| | - J Scott Miners
- Institute of Clinical Neurosciences, School of Clinical Sciences, Learning and Research Level 2, Southmead Hospital, University of Bristol, Bristol, BS10 5NB, UK
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15
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Anderson-Mooney AJ, Schmitt FA, Head E, Lott IT, Heilman KM. Gait dyspraxia as a clinical marker of cognitive decline in Down syndrome: A review of theory and proposed mechanisms. Brain Cogn 2016; 104:48-57. [PMID: 26930369 PMCID: PMC4801771 DOI: 10.1016/j.bandc.2016.02.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/13/2016] [Accepted: 02/21/2016] [Indexed: 12/15/2022]
Abstract
Down syndrome (DS) is the most common genetic cause of intellectual disability in children. With aging, DS is associated with an increased risk for Alzheimer's disease (AD). The development of AD neuropathology in individuals with DS can result in further disturbances in cognition and behavior and may significantly exacerbate caregiver burden. Early detection may allow for appropriate preparation by caregivers. Recent literature suggests that declines in gait may serve as an early marker of AD-related cognitive disorders; however, this relationship has not been examined in individuals with DS. The theory regarding gait dyspraxia and cognitive decline in the general population is reviewed, and potential applications to the population with individuals with DS are highlighted. Challenges and benefits in the line of inquiry are discussed. In particular, it appears that gait declines in aging individuals with DS may be associated with known declines in frontoparietal gray matter, development of AD-related pathology, and white matter losses in tracts critical to motor control. These changes are also potentially related to the cognitive and functional changes often observed during the same chronological period as gait declines in adults with DS. Gait declines may be an early marker of cognitive change, related to the development of underlying AD-related pathology, in individuals with DS. Future investigations in this area may provide insight into the clinical changes associated with development of AD pathology in both the population with DS and the general population, enhancing efforts for optimal patient and caregiver support and propelling investigations regarding safety/quality of life interventions and disease-modifying interventions.
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Affiliation(s)
- Amelia J Anderson-Mooney
- University of Kentucky College of Medicine, Department of Neurology, 740 S. Limestone, Suite B-101, Lexington, KY 40536, United States.
| | - Frederick A Schmitt
- University of Kentucky College of Medicine, Department of Neurology and Sanders-Brown Center on Aging, 800 S. Limestone, Room 312, Lexington, KY 40536, United States.
| | - Elizabeth Head
- University of Kentucky, Department of Molecular & Biomedical Pharmacology and Sanders-Brown Center on Aging, 800 S. Limestone, Room 203, Lexington, KY 40536, United States.
| | - Ira T Lott
- University of California - Irvine School of Medicine, Department of Pediatrics, Bldg 2 3rd Floor Rt 81, 101 The City Drive, Mail Code: 4482, Orange, CA 92668, United States.
| | - Kenneth M Heilman
- University of Florida College of Medicine, Department of Neurology, Room L3-100, McKnight Brain Institute, 1149 Newell Drive, Gainesville, FL 32611, United States.
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16
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Tosto G, Zimmerman ME, Hamilton JL, Carmichael OT, Brickman AM. The effect of white matter hyperintensities on neurodegeneration in mild cognitive impairment. Alzheimers Dement 2015; 11:1510-1519. [PMID: 26079417 PMCID: PMC4677059 DOI: 10.1016/j.jalz.2015.05.014] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 03/19/2015] [Accepted: 05/04/2015] [Indexed: 12/22/2022]
Abstract
INTRODUCTION It is unclear whether white matter hyperintensities (WMHs), magnetic resonance imaging markers of small-vessel cerebrovascular disease, promote neurodegeneration and associated clinical decline in Alzheimer's disease (AD), or simply co-occur with recognized pathogenic processes. METHODS In 169 patients with mild cognitive impairment, followed for 3 years, we examined the association of (1) baseline regional WMH and cerebral spinal fluid-derived t-tau (total tau) with entorhinal cortex atrophy rates, as a marker of AD-related neurodegeneration, and conversion to AD; and (2) baseline regional WMH with change in t-tau level. RESULTS In participants with low baseline t-tau, higher regional WMH volumes were associated with faster entorhinal cortex atrophy. Higher parietal WMH volume predicted conversion to AD in those with high t-tau. Higher parietal and occipital WMH volumes predicted increasing t-tau. DISCUSSION WMHs affect AD clinical and pathologic processes both directly and interacting with tau.
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Affiliation(s)
- Giuseppe Tosto
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Molly E Zimmerman
- Department of Psychology, Fordham University, Bronx, NY, USA; Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jamie L Hamilton
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | | | - Adam M Brickman
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
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17
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Cai Z, Wang C, He W, Tu H, Tang Z, Xiao M, Yan LJ. Cerebral small vessel disease and Alzheimer's disease. Clin Interv Aging 2015; 10:1695-704. [PMID: 26604717 PMCID: PMC4629951 DOI: 10.2147/cia.s90871] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Cerebral small vessel disease (CSVD) is a group of pathological processes with multifarious etiology and pathogenesis that are involved into the small arteries, arterioles, venules, and capillaries of the brain. CSVD mainly contains lacunar infarct or lacunar stroke, leukoaraiosis, Binswanger's disease, and cerebral microbleeds. CSVD is an important cerebral microvascular pathogenesis as it is the cause of 20% of strokes worldwide and the most common cause of cognitive impairment and dementia, including vascular dementia and Alzheimer's disease (AD). It has been well identified that CSVD contributes to the occurrence of AD. It seems that the treatment and prevention for cerebrovascular diseases with statins have such a role in the same function for AD. So far, there is no strong evidence-based medicine to support the idea, although increasing basic studies supported the fact that the treatment and prevention for cerebrovascular diseases will benefit AD. Furthermore, there is still lack of evidence in clinical application involved in specific drugs to benefit both AD and CSVD.
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Affiliation(s)
- Zhiyou Cai
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China
| | - Chuanling Wang
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China
| | - Wenbo He
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China
| | - Hanjun Tu
- Department of Basic Research Center, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China
| | - Zhengang Tang
- Department of Neurosurgery, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China
| | - Ming Xiao
- Department of Anatomy, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Liang-Jun Yan
- Department of Pharmaceutical Sciences, UNT System College of Pharmacy, University of North Texas Health Science Center, Fort Worth, TX, USA
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18
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Love S, Miners JS. White matter hypoperfusion and damage in dementia: post-mortem assessment. Brain Pathol 2015; 25:99-107. [PMID: 25521180 DOI: 10.1111/bpa.12223] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 10/08/2014] [Indexed: 01/19/2023] Open
Abstract
Neuroimaging has revealed a range of white matter abnormalities that are common in dementia, some that predict cognitive decline. The abnormalities may result from structural diseases of the cerebral vasculature, such as arteriolosclerosis and amyloid angiopathy, but can also be caused by nonstructural vascular abnormalities (eg, of vascular contractility or permeability), neurovascular instability or extracranial cardiac or vascular disease. Conventional histopathological assessment of the white matter has tended to conflate morphological vascular abnormalities with changes that reflect altered interstitial fluid dynamics or white matter ischemic damage, even though the latter may be of extracranial or nonstructural etiology. However, histopathology is being supplemented by biochemical approaches, including the measurement of proteins involved in the molecular responses to brain ischemia, myelin proteins differentially susceptible to ischemic damage, vessel-associated proteins that allow rapid measurement of microvessel density, markers of blood-brain barrier dysfunction and axonal injury, and mediators of white matter damage. By combining neuroimaging with histopathology and biochemical analysis, we can provide reproducible, quantitative data on the severity of white matter damage, and information on its etiology and pathogenesis. Together these have the potential to inform and improve treatment, particularly in forms of dementia to which white matter hypoperfusion makes a significant contribution.
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Affiliation(s)
- Seth Love
- Dementia Research Group, Institute of Clinical Neurosciences, University of Bristol, Learning and Research Level 2, Southmead Hospital, Bristol, UK
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Parra MA, Saarimäki H, Bastin ME, Londoño AC, Pettit L, Lopera F, Della Sala S, Abrahams S. Memory binding and white matter integrity in familial Alzheimer's disease. Brain 2015; 138:1355-69. [PMID: 25762465 DOI: 10.1093/brain/awv048] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 12/30/2014] [Indexed: 11/13/2022] Open
Abstract
Binding information in short-term and long-term memory are functions sensitive to Alzheimer's disease. They have been found to be affected in patients who meet criteria for familial Alzheimer's disease due to the mutation E280A of the PSEN1 gene. However, only short-term memory binding has been found to be affected in asymptomatic carriers of this mutation. The neural correlates of this dissociation are poorly understood. The present study used diffusion tensor magnetic resonance imaging to investigate whether the integrity of white matter structures could offer an account. A sample of 19 patients with familial Alzheimer's disease, 18 asymptomatic carriers and 21 non-carrier controls underwent diffusion tensor magnetic resonance imaging, neuropsychological and memory binding assessment. The short-term memory binding task required participants to detect changes across two consecutive screens displaying arrays of shapes, colours, or shape-colour bindings. The long-term memory binding task was a Paired Associates Learning Test. Performance on these tasks were entered into regression models. Relative to controls, patients with familial Alzheimer's disease performed poorly on both memory binding tasks. Asymptomatic carriers differed from controls only in the short-term memory binding task. White matter integrity explained poor memory binding performance only in patients with familial Alzheimer's disease. White matter water diffusion metrics from the frontal lobe accounted for poor performance on both memory binding tasks. Dissociations were found in the genu of corpus callosum which accounted for short-term memory binding impairments and in the hippocampal part of cingulum bundle which accounted for long-term memory binding deficits. The results indicate that white matter structures in the frontal and temporal lobes are vulnerable to the early stages of familial Alzheimer's disease and their damage is associated with impairments in two memory binding functions known to be markers for Alzheimer's disease.
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Affiliation(s)
- Mario A Parra
- 1 Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK 2 Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK 3 UDP-INECO Foundation Core on Neuroscience (UIFCoN), Diego Portales University, Santiago, Chile 4 Alzheimer Scotland Dementia Research Centre and Scottish Dementia Clinical Research Network, NHS Scotland 5 Neuroscience Group, University of Antioquia, Antioquia, Colombia
| | - Heini Saarimäki
- 1 Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK
| | - Mark E Bastin
- 2 Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - Ana C Londoño
- 5 Neuroscience Group, University of Antioquia, Antioquia, Colombia
| | - Lewis Pettit
- 1 Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK
| | - Francisco Lopera
- 5 Neuroscience Group, University of Antioquia, Antioquia, Colombia
| | - Sergio Della Sala
- 1 Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK 2 Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - Sharon Abrahams
- 1 Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK 2 Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK 6 Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, UK
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Esiri M, Chance S, Joachim C, Warden D, Smallwood A, Sloan C, Christie S, Wilcock G, Smith AD. Cerebral amyloid angiopathy, subcortical white matter disease and dementia: literature review and study in OPTIMA. Brain Pathol 2015; 25:51-62. [PMID: 25521177 PMCID: PMC8028928 DOI: 10.1111/bpa.12221] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 10/08/2014] [Indexed: 12/23/2022] Open
Abstract
Cerebral amyloid angiopathy (CAA) is of increasing clinical and research interest as the ability to detect it and its consequences by neuroimaging in living subjects has advanced. There is also increasing interest in understanding its possible role in the development of intracerebral hemorrhage, Alzheimer's disease (AD) and vascular dementia. In this article, the literature on this subject is reviewed and novel findings relating CAA to subcortical white matter damage in 224 subjects in the Oxford project to Investigate Memory and Ageing (OPTIMA) are reported. The relationship between CAA and subcortical tissue damage in the OPTIMA subjects was found to be critically dependent on ApoE genotype, there being a positive relationship between measures of CAA and subcortical small vessel disease in ApoEε4 carriers and a significant negative relationship in ApoEε2 carriers. These findings draw attention, as have many other studies, to the importance of ApoE genotype as a major risk factor not only for dementia but also for damage to blood vessels in the aging brain.
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Affiliation(s)
- Margaret Esiri
- Neuropathology DepartmentNuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Steven Chance
- Neuropathology DepartmentNuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Catharine Joachim
- Neuropathology DepartmentNuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Donald Warden
- Department of PharmacologyUniversity of OxfordOxfordUK
| | | | - Carolyn Sloan
- Neuropathology DepartmentNuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Sharon Christie
- Nuffield Department of Clinical NeurosciencesOPTIMAUniversity of OxfordOxfordUK
| | - Gordon Wilcock
- Nuffield Department of Clinical NeurosciencesOPTIMAUniversity of OxfordOxfordUK
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Al-Mashhadi S, Simpson JE, Heath PR, Dickman M, Forster G, Matthews FE, Brayne C, Ince PG, Wharton SB. Oxidative Glial Cell Damage Associated with White Matter Lesions in the Aging Human Brain. Brain Pathol 2014; 25:565-74. [PMID: 25311358 PMCID: PMC4861214 DOI: 10.1111/bpa.12216] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/07/2014] [Indexed: 01/04/2023] Open
Abstract
White matter lesions (WML) are common in brain aging and are associated with dementia. We aimed to investigate whether oxidative DNA damage and occur in WML and in apparently normal white matter in cases with lesions. Tissue from WML and control white matter from brains with lesions (controls lesional) and without lesions (controls non‐lesional) were obtained, using post‐mortem magnetic resonance imaging‐guided sampling, from the Medical Research Council Cognitive Function and Ageing Study. Oxidative damage was assessed by immunohistochemistry to 8‐hydroxy‐2′‐deoxoguanosine (8‐OHdG) and Western blotting for malondialdehyde. DNA response was assessed by phosphorylated histone H2AX (γH2AX), p53, senescence markers and by quantitative Reverse transcription polymerase chain reaction (RT‐PCR) panel for candidate DNA damage‐associated genes. 8‐OHdG was expressed in glia and endothelium, with increased expression in both WML and controls lesional compared with controls non‐lesional (P < 0.001). γH2Ax showed a similar, although attenuated difference among groups (P = 0.03). Expression of senescence‐associated β‐galactosidase and p16 suggested induction of senescence mechanisms in glia. Oxidative DNA damage and a DNA damage response are features of WML pathogenesis and suggest candidate mechanisms for glial dysfunction. Their expression in apparently normal white matter in cases with WML suggests that white matter dysfunction is not restricted to lesions. The role of this field‐effect lesion pathogenesis and cognitive impairment are areas to be defined.
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Affiliation(s)
- Sufana Al-Mashhadi
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK.,King Fahad Medical City, Riyadh, Saudi Arabia
| | - Julie E Simpson
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Paul R Heath
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Mark Dickman
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - Gillian Forster
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Fiona E Matthews
- Medical Research Council Biostatistics Unit, University of Cambridge, Cambridge, UK
| | - Carol Brayne
- Institute of Public Health, University of Cambridge, Cambridge, UK
| | - Paul G Ince
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Stephen B Wharton
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
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22
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Oishi K, Lyketsos CG. Alzheimer's disease and the fornix. Front Aging Neurosci 2014; 6:241. [PMID: 25309426 PMCID: PMC4161001 DOI: 10.3389/fnagi.2014.00241] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/22/2014] [Indexed: 11/27/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common form of neurodegenerative dementia. Researchers have long been focused on the cortical pathology of AD, since the most important pathologic features are the senile plaques found in the cortex, and the neurofibrillary tangles and neuronal loss that begin in the entorhinal cortex and the hippocampus. In addition to these gray matter (GM) structures, histopathological studies indicate that the white matter (WM) is also a good target for both the early diagnosis of AD and for monitoring disease progression. The fornix is a WM bundle that constitutes a core element of the limbic circuits, and is one of the most important anatomical structures related to memory. Functional and anatomical features of the fornix have naturally captured researchers’ attention as possible diagnostic and prognostic markers of AD. Indeed, neurodegeneration of the fornix has been histologically observed in AD, and growing evidence indicates that the alterations seen in the fornix are potentially a good marker to predict future conversion from mild cognitive impairment (MCI) to AD, and even from cognitively normal individuals to AD. The degree of alteration is correlated with the degree of memory impairment, indicating the potential for the use of the fornix as a functional marker. Moreover, there have been attempts to stimulate the fornix using deep brain stimulation (DBS) to augment cognitive function in AD, and ongoing research has suggested positive effects of DBS on brain glucose metabolism in AD patients. On the other hand, disease specificity for fornix degeneration, methodologies to evaluate fornix degeneration, and the clinical significance of the fornix DBS, especially for the long-term impact on the quality of life, are mostly unknown and need to be elucidated.
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Affiliation(s)
- Kenichi Oishi
- The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University Baltimore, MD, USA
| | - Constantine G Lyketsos
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins Bayview and Johns Hopkins Medicine Baltimore, MD, USA
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Soluble amyloid beta levels are elevated in the white matter of Alzheimer's patients, independent of cortical plaque severity. Acta Neuropathol Commun 2014; 2:83. [PMID: 25129614 PMCID: PMC4147157 DOI: 10.1186/s40478-014-0083-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 07/04/2014] [Indexed: 12/03/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common neurodegenerative disease and the leading cause of dementia. In addition to grey matter pathology, white matter changes are now recognized as an important pathological feature in the emergence of the disease. Despite growing recognition of the importance of white matter abnormalities in the pathogenesis of AD, the causes of white matter degeneration are still unknown. While multiple studies propose Wallerian-like degeneration as the source of white matter change, others suggest that primary white matter pathology may be due, at least in part, to other mechanisms, including local effects of toxic Aβ peptides. In the current study, we investigated levels of soluble amyloid-beta (Aβ) in white matter of AD patients (n=12) compared with controls (n=10). Fresh frozen white matter samples were obtained from anterior (Brodmann area 9) and posterior (Brodmann area 1, 2 and 3) areas of post-mortem AD and control brains. ELISA was used to examine levels of soluble Aβ -42 and Aβ -40. Total cortical neuritic plaque severity rating was derived from individual ratings in the following areas of cortex: mid-frontal, superior temporal, pre-central, inferior parietal, hippocampus (CA1), subiculum, entorhinal cortex, transentorhinal cortex, inferior temporal, amygdala and basal forebrain. Compared with controls, AD samples had higher white matter levels of both soluble Aβ -42 and Aβ -40. While no regional white matter differences were found in Aβ -40, Aβ -42 levels were higher in anterior regions than in posterior regions across both groups. After statistically controlling for total cortical neuritic plaque severity, differences in both soluble Aβ -42 and Aβ -40 between the groups remained, suggesting that white matter Aβ peptides accumulate independent of overall grey matter fibrillar amyloid pathology and are not simply a reflection of overall amyloid burden. These results shed light on one potential mechanism through which white matter degeneration may occur in AD. Given that white matter degeneration may be an early marker of disease, preceding grey matter atrophy, understanding the mechanisms and risk factors that may lead to white matter loss could help to identify those at high risk and to intervene earlier in the pathogenic process.
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Adluru N, Destiche DJ, Lu SYF, Doran ST, Birdsill AC, Melah KE, Okonkwo OC, Alexander AL, Dowling NM, Johnson SC, Sager MA, Bendlin BB. White matter microstructure in late middle-age: Effects of apolipoprotein E4 and parental family history of Alzheimer's disease. NEUROIMAGE-CLINICAL 2014; 4:730-42. [PMID: 24936424 PMCID: PMC4053649 DOI: 10.1016/j.nicl.2014.04.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 04/16/2014] [Accepted: 04/17/2014] [Indexed: 01/05/2023]
Abstract
INTRODUCTION Little is still known about the effects of risk factors for Alzheimer's disease (AD) on white matter microstructure in cognitively healthy adults. The purpose of this cross-sectional study was to assess the effect of two well-known risk factors for AD, parental family history and APOE4 genotype. METHODS This study included 343 participants from the Wisconsin Registry for Alzheimer's Prevention, who underwent diffusion tensor imaging (DTI). A region of interest analysis was performed on fractional anisotropy maps, in addition to mean, radial, and axial diffusivity maps, aligned to a common template space using a diffeomorphic, tensor-based registration method. The analysis focused on brain regions known to be affected in AD including the corpus callosum, superior longitudinal fasciculus, fornix, cingulum, and uncinate fasciculus. Analyses assessed the impact of APOE4, parental family history of AD, age, and sex on white matter microstructure in late middle-aged participants (aged 47-76 years). RESULTS Both APOE4 and parental family history were associated with microstructural white matter differences. Participants with parental family history of AD had higher FA in the genu of the corpus callosum and the superior longitudinal fasciculus. We observed an interaction between family history and APOE4, where participants who were family history positive but APOE4 negative had lower axial diffusivity in the uncinate fasciculus, and participants who were both family history positive and APOE4 positive had higher axial diffusivity in this region. We also observed an interaction between APOE4 and age, whereby older participants (=65 years of age) who were APOE4 carriers, had higher MD in the superior longitudinal fasciculus and in the portion of the cingulum bundle running adjacent to the cingulate cortex, compared to non-carriers. Older participants who were APOE4 carriers also showed higher radial diffusivity in the genu compared to non-carriers. Across all participants, age had an effect on FA, MD, and axial and radial diffusivities. Sex differences were observed in FA and radial diffusivity. CONCLUSION APOE4 genotype, parental family history of AD, age, and sex are all associated with microstructural white matter differences in late middle-aged adults. In participants at risk for AD, alterations in diffusion characteristics-both expected and unexpected-may represent cellular changes occurring at the earliest disease stages, but further work is needed. Higher mean, radial, and axial diffusivities were observed in participants who are more likely to be experiencing later stage preclinical pathology, including participants who were both older and carried APOE4, or who were positive for both APOE4 and parental family history of AD.
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Affiliation(s)
- Nagesh Adluru
- Waisman Laboratory for Brain Imaging and Behavior, Madison, WI, USA
| | | | | | - Samuel T Doran
- Waisman Laboratory for Brain Imaging and Behavior, Madison, WI, USA
| | - Alex C Birdsill
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
| | - Kelsey E Melah
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
| | - Ozioma C Okonkwo
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
| | - Andrew L Alexander
- Waisman Laboratory for Brain Imaging and Behavior, Madison, WI, USA ; Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Madison, WI 53705, USA ; University of Wisconsin School of Medicine and Public Health, Department of Psychiatry, 6001 Research Park Blvd, Madison, WI 53719, USA
| | - N Maritza Dowling
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA ; Department of Biostatistics and Medical Informatics, 600 Highland Avenue, Madison, WI 53792, USA
| | - Sterling C Johnson
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA ; Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veteran's Hospital, 2500 Overlook Terrace, Madison, WI 53705, USA ; Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, 7818 Big Sky Drive, Madison, WI 53719, USA
| | - Mark A Sager
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA ; Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veteran's Hospital, 2500 Overlook Terrace, Madison, WI 53705, USA ; Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, 7818 Big Sky Drive, Madison, WI 53719, USA
| | - Barbara B Bendlin
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
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Kljajevic V, Meyer P, Holzmann C, Dyrba M, Kasper E, Bokde ALW, Fellgiebel A, Meindl T, Hampel H, Teipel S. The ε4 genotype of apolipoprotein E and white matter integrity in Alzheimer's disease. Alzheimers Dement 2013; 10:401-4. [PMID: 23706516 DOI: 10.1016/j.jalz.2013.02.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 02/01/2013] [Accepted: 02/07/2013] [Indexed: 11/19/2022]
Abstract
BACKGROUND In this multicenter study, we investigated a possible association between the APOE ε4 allele and white matter (WM) integrity in Alzheimer's disease (AD) using diffusion tensor imaging (DTI). METHODS We analyzed fractional anisotropy (FA) and mean diffusivity (MD) as indices of WM integrity in 70 AD patients (35 APOE ε4 carriers, 35 noncarriers) and 56 healthy control (HC) subjects (28 APOE ε4 carriers, 28 noncarriers). APOE ε4 carriers and noncarriers were matched for age and gender within each diagnostic group. RESULTS We found significant effects of diagnosis (Pcorrected < .05 [FWE]; i.e., smaller FA values and larger MD values in AD patients compared with HCs) and significant effects (P < .001) of APOE ε4 carrier status on MD in HCs but not in AD subjects. CONCLUSIONS The results indicate that APOE ε4 has a moderate effect on WM integrity in HCs, but no effect on WM integrity in manifest AD.
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Affiliation(s)
- Vanja Kljajevic
- DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany.
| | - Peter Meyer
- Institute of Medical Genetics, University Medicine, Rostock, Germany
| | - Carsten Holzmann
- Institute of Medical Genetics, University Medicine, Rostock, Germany
| | - Martin Dyrba
- DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany; Mobile Multimedia Information Systems Group, University of Rostock, Rostock, Germany
| | - Elisabeth Kasper
- DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany
| | - Arun L W Bokde
- Cognitive Systems Group, Discipline of Psychiatry, School of Medicine, Trinity College Dublin, Dublin, Ireland; Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Andreas Fellgiebel
- Department of Psychiatry, University Medical Center of Mainz, Mainz, Germany
| | - Thomas Meindl
- Department of Magnetic Resonance Imaging, Institute for Clinical Radiology, Ludwig Maximilian University Munich, Munich, Germany
| | - Harald Hampel
- Department of Psychiatry, University of Frankfurt, Frankfurt, Germany
| | - Stefan Teipel
- DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany; Department of Psychiatry, University of Rostock, Rostock, Germany
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Abstract
PURPOSE OF REVIEW Alzheimer's disease has long been primarily considered a disease of gray matter. However, convergent evidence has suggested that white matter abnormalities are also important components of Alzheimer's disease. We undertook a review of the recent findings of Alzheimer's disease related white matter aberrations identified in patients with Alzheimer's disease and using in-vitro and in-vivo models, and discuss the potential causes of white matter damage in Alzheimer's disease. In doing so, we aim to provide a renewed insight into white matter changes in Alzheimer's disease and related dementias. RECENT FINDINGS Neuroimaging studies have found that patients with preclinical Alzheimer's disease have widespread white matter abnormalities at a stage similar to those reported in Alzheimer's disease, whereas gray matter structures were relatively intact. In addition, demyelination of the white matter is reported to occur prior to the presence of amyloid-β plaques and neurofibrillary tangles in the presymptomatic stages of Alzheimer's disease. Furthermore, in a mouse model of Alzheimer's disease, axonal disease due to impaired axonal transport was shown to precede and drive downstream production and aggregation of amyloid β peptides. SUMMARY White matter abnormalities not only represent an early neuropathological event in Alzheimer's disease but may also play an important role in the pathogenesis and diagnosis of Alzheimer's disease.
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Kurczek J, Duff MC. Intact discourse cohesion and coherence following bilateral ventromedial prefrontal cortex. BRAIN AND LANGUAGE 2012; 123:222-227. [PMID: 23102898 PMCID: PMC3541036 DOI: 10.1016/j.bandl.2012.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 08/17/2012] [Accepted: 09/08/2012] [Indexed: 06/01/2023]
Abstract
Discourse cohesion and coherence give communication its continuity providing the grammatical and lexical links that hold an utterance or text together and give it meaning. Researchers often link cohesion and coherence deficits to the frontal lobes by drawing attention to frontal lobe dysfunction in populations where discourse cohesion and coherence deficits are reported and through attribution of these deficits to underlying cognitive impairments putatively associated with the frontal lobes. We examined the distinct contribution of a region of the frontal lobes, the ventromedial prefrontal cortex (vmPFC), to discourse cohesion and coherence across a range of discourse tasks. We found that bilateral vmPFC damage does not impair cohesion and coherence in spoken discourse. This study provides insights into the contribution of the major anatomical subdivisions of the frontal lobes to language use and furthers our understanding of the neural and cognitive underpinnings of discourse cohesion and coherence.
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Affiliation(s)
- Jake Kurczek
- Department of Neurology, Division of Cognitive Neuroscience, University of Iowa
- Neuroscience Graduate Program, University of Iowa
| | - Melissa C. Duff
- Department of Neurology, Division of Cognitive Neuroscience, University of Iowa
- Neuroscience Graduate Program, University of Iowa
- Department of Communication Sciences and Disorders, University of Iowa
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28
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Multiple DTI index analysis in normal aging, amnestic MCI and AD. Relationship with neuropsychological performance. Neurobiol Aging 2012; 33:61-74. [PMID: 20371138 DOI: 10.1016/j.neurobiolaging.2010.02.004] [Citation(s) in RCA: 200] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 02/03/2010] [Accepted: 02/11/2010] [Indexed: 11/23/2022]
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29
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Polvikoski TM, van Straaten ECW, Barkhof F, Sulkava R, Aronen HJ, Niinistö L, Oinas M, Scheltens P, Erkinjuntti T, Kalaria RN. Frontal lobe white matter hyperintensities and neurofibrillary pathology in the oldest old. Neurology 2010; 75:2071-8. [PMID: 21048201 DOI: 10.1212/wnl.0b013e318200d6f9] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Current studies suggest an interaction between vascular mechanisms and neurodegenerative processes that leads to late-onset Alzheimer disease (AD). We tested whether AD pathology was associated with white matter hyperintensities (WMH) or cerebral infarcts in the oldest old individuals. METHODS Brains from 132 subjects over 85 years old, who came to autopsy from the Vantaa 85+ population-based cohort, were scanned by postmortem MRI and examined for neuropathologic changes. Coronal images were analyzed to determine the degree of frontal and parietal periventricular WMH (PVWMH) and deep WMH (DWMH) and cerebral infarcts. Neuropathologic variables included Consortium to Establish a Registry for Alzheimer's Disease scores for neuritic plaques and Braak staging among subjects in 5 groups: normal aging (NA), borderline with insufficient AD pathology, AD, AD plus other pathology, and other primary degenerative diseases. RESULTS Frontal DWMH were detected in >50% of the sample. Both frontal PVWMH and DWMH were significantly more extensive in the AD group compared to the NA group or the NA and borderline groups combined. Frontal PVWMH and DWMH were also associated with increased Braak staging (p = 0.03) and the neuritic plaque load (p = 0.01). Further analysis revealed there were a greater number of cerebral infarcts associated with frontal DWMH (p = 0.03) but not with frontal PVWMH. CONCLUSIONS Our study showed an association between neurofibrillary pathology and frontal PVWMH and DWMH (rather than parietal), as a surrogate of small vessel disease, particularly in very old community-dwelling individuals.
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Affiliation(s)
- T M Polvikoski
- Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, UK
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30
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Wang Z, Guo X, Qi Z, Yao L, Li K. Whole-brain voxel-based morphometry of white matter in mild cognitive impairment. Eur J Radiol 2010; 75:129-33. [DOI: 10.1016/j.ejrad.2009.04.041] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Accepted: 04/15/2009] [Indexed: 11/25/2022]
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31
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Leskovjan AC, Kretlow A, Miller LM. Fourier transform infrared imaging showing reduced unsaturated lipid content in the hippocampus of a mouse model of Alzheimer's disease. Anal Chem 2010; 82:2711-6. [PMID: 20187625 PMCID: PMC2848295 DOI: 10.1021/ac1002728] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Polyunsaturated fatty acids are essential to brain functions such as membrane fluidity, signal transduction, and cell survival. It is also thought that low levels of unsaturated lipid in the brain may contribute to Alzheimer's disease (AD) risk or severity. However, it is not known how accumulation of unsaturated lipids is affected in different regions of the hippocampus, which is a central target of AD plaque pathology, during aging. In this study, we used Fourier transform infrared imaging (FTIRI) to visualize the unsaturated lipid content in specific regions of the hippocampus in the PSAPP mouse model of AD as a function of plaque formation. Specifically, the unsaturated lipid content was imaged using the olefinic =CH stretching mode at 3012 cm(-1). The axonal, dendritic, and somatic layers of the hippocampus were examined in the mice at 13, 24, 40, and 56 weeks old. Results showed that lipid unsaturation in the axonal layer was significantly increased with normal aging in control (CNT) mice (p < 0.01) but remained low and relatively constant in PSAPP mice. Thus, these findings indicate that unsaturated lipid content is reduced in hippocampal white matter during amyloid pathogenesis and that maintaining unsaturated lipid content early in the disease may be critical in avoiding progression of the disease.
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Affiliation(s)
- Andreana C. Leskovjan
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973
| | - Ariane Kretlow
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973
| | - Lisa M. Miller
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973
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Bartzokis G, Lu PH, Mintz J. Human brain myelination and amyloid beta deposition in Alzheimer's disease. Alzheimers Dement 2009; 3:122-5. [PMID: 18596894 DOI: 10.1016/j.jalz.2007.01.019] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We hypothesized that myelin breakdown in vulnerable late-myelinating regions releases oligodendrocyte- and myelin-associated iron that promotes amyloid beta (A beta) oligomerization, its associated toxicity, and the deposition of oligomerized A beta and iron in neuritic plaques observed in Alzheimer's disease (AD). The model was tested by using published maps of cortical myelination from 1901 and recent in vivo imaging maps of A beta deposits in humans. The data show that in AD, radiolabeled ligands detect A beta deposition in a distribution that matches the map of late-myelinating regions. Furthermore, the strikingly lower ability of this imaging ligand to bind A beta in animal models is consistent with the much lower levels of myelin and associated iron levels in rodents when compared with humans. The hypotheses derived from the "myelin model" are testable with current imaging methods and have important implications for therapeutic interventions that should be expanded to include novel targets such as oligodendrocytes, myelin, and brain iron.
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Affiliation(s)
- George Bartzokis
- Department of Neurology, The David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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Bartzokis G. Alzheimer's disease as homeostatic responses to age-related myelin breakdown. Neurobiol Aging 2009; 32:1341-71. [PMID: 19775776 DOI: 10.1016/j.neurobiolaging.2009.08.007] [Citation(s) in RCA: 386] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2008] [Revised: 08/13/2009] [Accepted: 08/17/2009] [Indexed: 12/11/2022]
Abstract
The amyloid hypothesis (AH) of Alzheimer's disease (AD) posits that the fundamental cause of AD is the accumulation of the peptide amyloid beta (Aβ) in the brain. This hypothesis has been supported by observations that genetic defects in amyloid precursor protein (APP) and presenilin increase Aβ production and cause familial AD (FAD). The AH is widely accepted but does not account for important phenomena including recent failures of clinical trials to impact dementia in humans even after successfully reducing Aβ deposits. Herein, the AH is viewed from the broader overarching perspective of the myelin model of the human brain that focuses on functioning brain circuits and encompasses white matter and myelin in addition to neurons and synapses. The model proposes that the recently evolved and extensive myelination of the human brain underlies both our unique abilities and susceptibility to highly prevalent age-related neuropsychiatric disorders such as late onset AD (LOAD). It regards oligodendrocytes and the myelin they produce as being both critical for circuit function and uniquely vulnerable to damage. This perspective reframes key observations such as axonal transport disruptions, formation of axonal swellings/sphenoids and neuritic plaques, and proteinaceous deposits such as Aβ and tau as by-products of homeostatic myelin repair processes. It delineates empirically testable mechanisms of action for genes underlying FAD and LOAD and provides "upstream" treatment targets. Such interventions could potentially treat multiple degenerative brain disorders by mitigating the effects of aging and associated changes in iron, cholesterol, and free radicals on oligodendrocytes and their myelin.
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Affiliation(s)
- George Bartzokis
- Department of Psychiatry and Biobehavioral Sciences, The David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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Weller RO, Boche D, Nicoll JAR. Microvasculature changes and cerebral amyloid angiopathy in Alzheimer's disease and their potential impact on therapy. Acta Neuropathol 2009; 118:87-102. [PMID: 19234858 DOI: 10.1007/s00401-009-0498-z] [Citation(s) in RCA: 204] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 02/08/2009] [Accepted: 02/09/2009] [Indexed: 12/25/2022]
Abstract
The introduction of immunotherapy and its ultimate success will require re-evaluation of the pathogenesis of Alzheimer's disease particularly with regard to the role of the ageing microvasculature and the effects of APOE genotype. Arteries in the brain have two major functions (a) delivery of blood and (b) elimination of interstitial fluid and solutes, including amyloid-beta (Abeta), along perivascular pathways (lymphatic drainage). Both these functions fail with age and particularly severely in Alzheimer's disease and vascular dementia. Accumulation of Abeta as plaques in brain parenchyma and artery walls as cerebral amyloid angiopathy (CAA) is associated with failure of perivascular elimination of Abeta from the brain in the elderly and in Alzheimer's disease. High levels of soluble Abeta in the brain correlate with cognitive decline in Alzheimer's disease and reflect the failure of perivascular drainage of solutes from the brain and loss of homeostasis of the neuronal environment. Clinically and pathologically, there is a spectrum of disease related to functional failure of the ageing microvasculature with "pure" Alzheimer's disease at one end of the spectrum and vascular dementia at the other end. Changes in the cerebral microvasculature with age have a potential impact on therapy with cholinesterase inhibitors and especially on immunotherapy that removes Abeta from plaques in the brain, but results in an increase in severity of CAA and no clear improvement in cognition. Drainage of Abeta along perivascular pathways in ageing artery walls may need to be improved to maximise the potential for improvement of cognitive function with immunotherapy.
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Affiliation(s)
- Roy O Weller
- Clinical Neurosciences, University of Southampton School of Medicine, LD74, South Laboratory & Pathology Block, Southampton General Hospital, Southampton SO166YD, UK.
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Henry-Feugeas MC, Roy C, Baron G, Schouman-Claeys E. Leukoaraiosis and pulse-wave encephalopathy: observations with phase-contrast MRI in mild cognitive impairment. J Neuroradiol 2009; 36:212-8. [PMID: 19250677 DOI: 10.1016/j.neurad.2009.01.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE To test the pathogenic hypothesis of a breakdown in the vital buffering of the arterial pulsations behind leukoaraiosis (LA) in mild cognitive impairment (MCI). METHODS Seventy-one elderly patients with MCI underwent a combined structural and dynamic MR examination (3D T1-weighted and fast-FLAIR T2-weighted sequences, phase contrast sequences). Arterial indices of pulsatility (IP) and composite indicators of the amplitude transfer function between cerebrospinal fluid and cerebral venous flow (Icsf/veins) were used to assess the large artery stiffness and the intracranial compliance respectively. Cerebral total arterial blood flow (tCBF), superficial and deep venous flow rates were also measured. Intracranial dynamic parameters and potential confounders including age, gender and vascular risk factors were compared between two groups respectively with and without significant LA. RESULTS The only dynamic changes on multivariate analyse were an IP increase, a lowering of deep venous outflow and Icsf/veins in patients with LA. There was a significant interaction between IP and Icsf/veins in the logistic regression: as compared with patients with low IP (suggestive of high large artery compliance) and high Icsf/veins (suggestive of high intracranial compliance), the adjusted odds ratios for the presence of LA were 9 (95% CI 1-64, P=0.02) in cases of both high IP and Icsf/veins, 10 (95% CI 1-64, P=0.02) in cases of both high IP and low Icsf/veins and 19 (95% CI 3-127, P=0.002) in cases of both low IP and Icsf/veins. CONCLUSION LA may reflect an arteriosclerotic and/or resistive pulse wave encephalopathy in MCI.
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Affiliation(s)
- M-C Henry-Feugeas
- Department of Radiology, Bichat-Claude-Bernard University Hospital, AP-HP, 46, rue Henri-Huchard, 75877 Paris cedex 18, France.
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Fodero-Tavoletti MT, Rowe CC, McLean CA, Leone L, Li QX, Masters CL, Cappai R, Villemagne VL. Characterization of PiB binding to white matter in Alzheimer disease and other dementias. J Nucl Med 2009; 50:198-204. [PMID: 19164220 DOI: 10.2967/jnumed.108.057984] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
UNLABELLED 11C-Pittsburgh Compound B (11C-PiB) PET has demonstrated significantly higher PiB retention in the gray matter of Alzheimer disease (AD) patients than in healthy controls (HCs). PiB is similarly retained within the white matter of HC and AD brains. Although the specificity of PiB for Abeta plaques in gray matter has been well described, the nature of PiB binding to white matter remains unclear. In this study, we characterized the binding of PiB to human white matter homogenates. METHODS In vitro binding studies were conducted using 3H-PiB (0.1-500 nM) and white matter brain homogenates (100 microg) from 3 AD patients and 3 HCs. Nonspecific binding was determined using PiB (1 microM). White matter from the same patients was also analyzed by immunofluorescence/immunohistochemistry (IF/IHC) microscopy and Western blotting for Abeta expression. White matter kinetics were also characterized in vivo through 11C-PiB PET studies in 27 HCs and 34 patients with dementia. IF/IHC experiments were conducted on 1 postmortem patient with dementia, to compare with the 11C-PiB distribution volume ratio data acquired 23 mo earlier. RESULTS In vitro saturation studies indicated that 3H-PiB binds nonspecifically to white matter brain homogenates. PiB fluorescence staining of AD and HC brain sections was consistent with absence of Abeta in IHC staining. Higher gray matter-to-white matter ratios were observed in IHC images than in 11C-PiB PET images. CONCLUSION These studies suggest that PiB binding to white matter is mainly nonsaturable and nonspecific and that PiB retention in the 11C-PiB PET studies is largely attributable to slower PiB white matter kinetics.
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Affiliation(s)
- Michelle T Fodero-Tavoletti
- Department of Pathology, University of Melbourne, and Department of Nuclear Medicine, Centre for PET, Austin Hospital, Heidelberg, Victoria, Australia
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Keage HAD, Carare RO, Friedland RP, Ince PG, Love S, Nicoll JA, Wharton SB, Weller RO, Brayne C. Population studies of sporadic cerebral amyloid angiopathy and dementia: a systematic review. BMC Neurol 2009; 9:3. [PMID: 19144113 PMCID: PMC2647900 DOI: 10.1186/1471-2377-9-3] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Accepted: 01/13/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Deposition of amyloid-beta (Abeta) in vessel walls of the brain as cerebral amyloid angiopathy (CAA) could be a major factor in the pathogenesis of dementia. Here we investigate the relationship between dementia and the prevalence of CAA in older populations. We searched the literature for prospective population-based epidemiological clinicopathological studies, free of the biases of other sampling techniques, which were used as a comparison. METHODS To identify population-based studies assessing CAA and dementia, a previous systematic review of population-based clinicopathological studies of ageing and dementia was employed. To identify selected-sample studies, PsychInfo (1806-April Week 3 2008), OVID MEDLINE (1950-April Week 2 2008) and Pubmed (searched 21 April 2008) databases were searched using the term "amyloid angiopathy". These databases were also employed to search for any population-based studies not included in the previous systematic review. Studies were included if they reported the prevalence of CAA relative to a dementia classification (clinical or neuropathological). RESULTS Four population-based studies were identified. They showed that on average 55-59% of those with dementia displayed CAA (of any severity) compared to 28-38% of the non-demented. 37-43% of the demented displayed severe CAA in contrast to 7-24% of the non-demented. There was no overlap in the range of these averages and they were less variable and lower than those reported in 38 selected sample studies (demented v non-demented: 32-100 v 0-77% regardless of severity; 0-50 v 0-11% for severe only). CONCLUSION CAA prevalence in populations is consistently higher in the demented as compared to the non-demented. This supports a significant role for CAA in the pathogenesis of dementia.
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Affiliation(s)
- Hannah A D Keage
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
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Simpson JE, Hosny O, Wharton SB, Heath PR, Holden H, Fernando MS, Matthews F, Forster G, O'Brien JT, Barber R, Kalaria RN, Brayne C, Shaw PJ, Lewis CE, Ince PG. Microarray RNA expression analysis of cerebral white matter lesions reveals changes in multiple functional pathways. Stroke 2008; 40:369-75. [PMID: 19109541 DOI: 10.1161/strokeaha.108.529214] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE White matter lesions (WML) in brain aging are linked to dementia and depression. Ischemia contributes to their pathogenesis but other mechanisms may contribute. We used RNA microarray analysis with functional pathway grouping as an unbiased approach to investigate evidence for additional pathogenetic mechanisms. METHODS WML were identified by MRI and pathology in brains donated to the Medical Research Council Cognitive Function and Ageing Study Cognitive Function and Aging Study. RNA was extracted to compare WML with nonlesional white matter samples from cases with lesions (WM[L]), and from cases with no lesions (WM[C]) using RNA microarray and pathway analysis. Functional pathways were validated for selected genes by quantitative real-time polymerase chain reaction and immunocytochemistry. RESULTS We identified 8 major pathways in which multiple genes showed altered RNA transcription (immune regulation, cell cycle, apoptosis, proteolysis, ion transport, cell structure, electron transport, metabolism) among 502 genes that were differentially expressed in WML compared to WM[C]. In WM[L], 409 genes were altered involving the same pathways. Genes selected to validate this microarray data all showed the expected changes in RNA levels and immunohistochemical expression of protein. CONCLUSIONS WML represent areas with a complex molecular phenotype. From this and previous evidence, WML may arise through tissue ischemia but may also reflect the contribution of additional factors like blood-brain barrier dysfunction. Differential expression of genes in WM[L] compared to WM[C] indicate a "field effect" in the seemingly normal surrounding white matter.
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Affiliation(s)
- Julie E Simpson
- Academic Units of Pathology, University of Sheffield, Sheffield, UK
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Stenset V, Hofoss D, Johnsen L, Skinningsrud A, Berstad AE, Negaard A, Reinvang I, Gjerstad L, Fladby T. White matter lesion severity is associated with reduced cognitive performances in patients with normal CSF Abeta42 levels. Acta Neurol Scand 2008; 118:373-8. [PMID: 18510598 DOI: 10.1111/j.1600-0404.2008.01045.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To identify possible associations between white matter lesions (WML) and cognition in patients with memory complaints, stratified in groups with normal and low cerebrospinal fluid (CSF) Abeta42 values. MATERIAL AND METHODS 215 consecutive patients with subjective memory complaints were retrospectively included. Patients were stratified into two groups with normal (n = 127) or low (n = 88) CSF Abeta42 levels (cut-off is 450 ng/l). Cognitive scores from the Mini-Mental State Examination (MMSE) and the Neurobehavioral Cognitive Status Examination (Cognistat) were used as continuous dependent variables in linear regression. WML load was used as a continuous independent variable and was scored with a visual rating scale. The regression model was corrected for possible confounding factors. RESULTS WML were significantly associated with MMSE and all Cognistat subscores except language (repetition and naming) and attention in patients with normal CSF Abeta42 levels. No significant associations were observed in patients with low CSF Abeta42. CONCLUSIONS WML were associated with affection of multiple cognitive domains, including delayed recall and executive functions, in patients with normal CSF Abeta42 levels. The lack of such associations for patients with low CSF Abeta42 (i.e. with evidence for amyloid deposition), suggests that amyloid pathology may obscure cognitive effects of WML.
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Affiliation(s)
- V Stenset
- Department of Neurology, Akershus University Hospital, Lørenskog, Norway.
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Bartzokis G, Lu PH, Geschwind DH, Tingus K, Huang D, Mendez MF, Edwards N, Mintz J. Apolipoprotein E affects both myelin breakdown and cognition: implications for age-related trajectories of decline into dementia. Biol Psychiatry 2007; 62:1380-7. [PMID: 17659264 DOI: 10.1016/j.biopsych.2007.03.024] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Revised: 01/25/2007] [Accepted: 03/19/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND Age-related myelin breakdown is most evident in later-myelinating white matter (LMwm) brain regions. This process might degrade cognitive processing speed (CPS) underlying age-related cognitive decline and the predominance of age as a risk factor for Alzheimer's disease (AD). Apolipoprotein E (ApoE) 4 allele is the second most important AD risk factor. We tested the hypothesis that ApoE4 accelerates age-related slowing in CPS through the process of myelin breakdown. METHODS Calculated transverse relaxation rates (R(2)), an indirect magnetic resonance imaging measure of myelin breakdown in LMwm, and measures of CPS were obtained in 22 ApoE4+ and 80 ApoE4-, healthy "younger-old" individuals. To assess specificity, contrasting early-myelinating white matter region and memory task were also examined. RESULTS The CPS versus LMwm R(2) remained significant in the ApoE4+ group even after age was statistically adjusted (r = .65, p = .001) and differed from the correlation observed in the ApoE4- group (Fisher's z test = 3.22, p < .002). No significant associations were observed with the contrast region and memory task in either ApoE subgroup. CONCLUSIONS A specific association between CPS and myelin breakdown in LMwm exists in asymptomatic "younger-old" individuals at increased genetic risk for AD. Although inferences of change over time and causality are limited by the cross-sectional study design, this finding lends support to the hypotheses that myelin breakdown underlies age-related slowing in CPS and that by altering the trajectory of myelin breakdown, ApoE alleles shift the age at onset of cognitive decline. Combined use of biomarkers and CPS measures might be useful in developing and targeting primary prevention treatments for AD.
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Affiliation(s)
- George Bartzokis
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
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Bartzokis G. Acetylcholinesterase inhibitors may improve myelin integrity. Biol Psychiatry 2007; 62:294-301. [PMID: 17070782 DOI: 10.1016/j.biopsych.2006.08.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 07/28/2006] [Accepted: 08/21/2006] [Indexed: 12/27/2022]
Abstract
Recent clinical trials have revealed that cholinergic treatments are efficacious in a wide spectrum of neuropsychiatric disorders that span the entire human lifespan and include disorders without cholinergic deficits. Furthermore, some clinical and epidemiological data suggest that cholinergic treatments have disease modifying/preventive effects. It is proposed that these observations can be usefully understood in a myelin-centered model of the human brain. The model proposes that the human brain's extensive myelination is the central evolutionary change that defines our uniqueness as a species and our unique vulnerability to highly prevalent neuropsychiatric disorders. Within the framework of this model the clinical, biochemical, and epidemiologic data can be reinterpreted to suggest that nonsynaptic effects of cholinergic treatments on the process of myelination and myelin repair contributes to their mechanism of action and especially to their disease modifying/preventive effects. The ability to test the model in human populations with safe and noninvasive imaging technologies makes it possible to undertake novel clinical trial efforts directed at primary prevention of some of the most prevalent and devastating of human disorders.
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Affiliation(s)
- George Bartzokis
- Department of Neurology, The Laboratory of Neuroimaging in the Division of Brain Mapping, The David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095-1769, USA.
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