1
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Avelar-Pereira B, Phillips CM, Hosseini SMH. Convergence of Accelerated Brain Volume Decline in Normal Aging and Alzheimer's Disease Pathology. J Alzheimers Dis 2024; 101:249-258. [PMID: 39177595 DOI: 10.3233/jad-231458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2024]
Abstract
Background Age represents the largest risk factor for Alzheimer's disease (AD) but is typically treated as a covariate. Still, there are similarities between brain regions affected in AD and those showing accelerated decline in normal aging, suggesting that the distinction between the two might fall on a spectrum. Objective Our goal was to identify regions showing accelerated atrophy across the brain and investigate whether these overlapped with regions involved in AD or where related to amyloid. Methods We used a longitudinal sample of 137 healthy older adults from the Alzheimer's Disease Neuroimaging Initiative (ADNI), who underwent magnetic resonance imaging (MRI). In addition, a total of 79 participants also had longitudinal positron emission tomography (PET) data. We computed linear-mixed effects models for brain regions declining faster than the average to investigate variability in the rate of change. Results 23 regions displayed a 0.5 standard deviation (SD) above average decline over 2 years. Of these, 52% overlapped with regions showing similar decline in a matched AD sample. Beyond this, the left precuneus, right superior frontal, transverse temporal, and superior temporal sulcus showed accelerated decline. Lastly, atrophy in the precuneus was associated with increased amyloid load. Conclusions Accelerated decline in normal aging might contribute to the detection of early signs of AD among healthy individuals.
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Affiliation(s)
- Bárbara Avelar-Pereira
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA, USA
- Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden
| | - Curran Michael Phillips
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA, USA
| | - S M Hadi Hosseini
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA, USA
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2
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Exploring the brain metabolic correlates of process-specific CSF biomarkers in patients with MCI due to Alzheimer's disease: preliminary data. Neurobiol Aging 2022; 117:212-221. [DOI: 10.1016/j.neurobiolaging.2022.03.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 03/08/2022] [Accepted: 03/15/2022] [Indexed: 12/30/2022]
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3
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Tremblay C, Serrano GE, Intorcia AJ, Curry J, Sue LI, Nelson CM, Walker JE, Glass MJ, Arce RA, Fleisher AS, Pontecorvo MJ, Atri A, Montine TJ, Chen K, Beach TG. Hemispheric Asymmetry and Atypical Lobar Progression of Alzheimer-Type Tauopathy. J Neuropathol Exp Neurol 2022; 81:158-171. [PMID: 35191506 DOI: 10.1093/jnen/nlac008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The spread of neurofibrillary tau pathology in Alzheimer disease (AD) mostly follows a stereotypical pattern of topographical progression but atypical patterns associated with interhemispheric asymmetry have been described. Because histopathological studies that used bilateral sampling are limited, this study aimed to assess interhemispheric tau pathology differences and the presence of topographically atypical cortical spreading patterns. Immunohistochemical staining for detection of tau pathology was performed in 23 regions of interest in 57 autopsy cases comparing bilateral cortical regions and hemispheres. Frequent mild (82% of cases) and occasional moderate (32%) interhemispheric density discrepancies were observed, whereas marked discrepancies were uncommon (7%) and restricted to occipital regions. Left and right hemispheric tau pathology dominance was observed with similar frequencies, except in Braak Stage VI that favored a left dominance. Interhemispheric Braak stage differences were observed in 16% of cases and were more frequent in advanced (IV-VI) versus early (I-III) stages. One atypical lobar topographical pattern in which occipital tau pathology density exceeded frontal lobe scores was identified in 4 cases favoring a left dominant asymmetry. We speculate that asymmetry and atypical topographical progression patterns may be associated with atypical AD clinical presentations and progression characteristics, which should be tested by comprehensive clinicopathological correlations.
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Affiliation(s)
- Cécilia Tremblay
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Geidy E Serrano
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Jasmine Curry
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Lucia I Sue
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Courtney M Nelson
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Jessica E Walker
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Michael J Glass
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Richard A Arce
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | - Alireza Atri
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA.,Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Thomas J Montine
- Department of Pathology, Stanford University, Stanford, California, USA
| | - Kewei Chen
- Banner Alzheimer's Institute, Phoenix, Arizona, USA.,School of Mathematics and Statistics, Arizona State University, Tempe, Arizona, USA.,Department of Neurology, College of Medicine Phoenix, University of Arizona, Tucson, Arizona, USA
| | - Thomas G Beach
- From the Banner Sun Health Research Institute, Sun City, Arizona, USA
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4
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Savarraj JPJ, Kitagawa R, Kim DH, Choi HA. White matter connectivity for early prediction of Alzheimer's disease. Technol Health Care 2021; 30:17-28. [PMID: 33998562 DOI: 10.3233/thc-192012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Early diagnosis of Alzheimer's disease (AD) remains challenging. It is speculated that structural atrophy in white matter tracts commences prior to the onset of AD symptoms. OBJECTIVE We hypothesize that disruptions in white matter tract connectivity precedes the onset of AD symptoms and these disruptions could be leveraged for early prediction of AD. METHODS Diffusion tensor images (DTI) from 52 subjects with mild cognitive impairment (MCI) were selected. Subjects were dichotomized into two age and gender matched groups; the MCI-AD group (22 subjects who progressed to develop AD) and the MCI-control group (who did not develop AD). DTI images were anatomically parcellated into 90 distinct regions ROIs followed by tractography methods to obtain different biophysical networks. Features extracted from these networks were used to train predictive algorithms with the objective of discriminating the MCI-AD and MCI-control groups. Model performance and best features are reported. RESULTS Up to 80% prediction accuracy was achieved using a combination of features from the 'right anterior cingulum' and 'right frontal superior medial'. Additionally, local network features were more useful than global in improving the model's performance. CONCLUSION Connectivity-based characterization of white matter tracts offers potential for early detection of MCI-AD and in the discovery of novel imaging biomarkers.
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5
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Edler MK, Munger EL, Meindl RS, Hopkins WD, Ely JJ, Erwin JM, Mufson EJ, Hof PR, Sherwood CC, Raghanti MA. Neuron loss associated with age but not Alzheimer's disease pathology in the chimpanzee brain. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190619. [PMID: 32951541 PMCID: PMC7540958 DOI: 10.1098/rstb.2019.0619] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2020] [Indexed: 12/25/2022] Open
Abstract
In the absence of disease, ageing in the human brain is accompanied by mild cognitive dysfunction, gradual volumetric atrophy, a lack of significant cell loss, moderate neuroinflammation, and an increase in the amyloid beta (Aβ) and tau proteins. Conversely, pathologic age-related conditions, particularly Alzheimer's disease (AD), result in extensive neocortical and hippocampal atrophy, neuron death, substantial Aβ plaque and tau-associated neurofibrillary tangle pathologies, glial activation and severe cognitive decline. Humans are considered uniquely susceptible to neurodegenerative disorders, although recent studies have revealed Aβ and tau pathology in non-human primate brains. Here, we investigate the effect of age and AD-like pathology on cell density in a large sample of postmortem chimpanzee brains (n = 28, ages 12-62 years). Using a stereologic, unbiased design, we quantified neuron density, glia density and glia:neuron ratio in the dorsolateral prefrontal cortex, middle temporal gyrus, and CA1 and CA3 hippocampal subfields. Ageing was associated with decreased CA1 and CA3 neuron densities, while AD pathologies were not correlated with changes in neuron or glia densities. Differing from cerebral ageing and AD in humans, these data indicate that chimpanzees exhibit regional neuron loss with ageing but appear protected from the severe cell death found in AD. This article is part of the theme issue 'Evolution of the primate ageing process'.
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Affiliation(s)
- Melissa K. Edler
- School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA
- Department of Anthropology, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
| | - Emily L. Munger
- School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA
- Department of Anthropology, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
| | - Richard S. Meindl
- School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA
- Department of Anthropology, Kent State University, Kent, OH 44242, USA
| | - William D. Hopkins
- Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Joseph M. Erwin
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USA
| | - Elliott J. Mufson
- Departments of Neurobiology and Neurology, Barrow Neurological Institute, Phoenix, AZ 85013, USA
| | - Patrick R. Hof
- Nash Family Department of Neuroscience, Ronald M. Loeb Center for Alzheimer's Disease, and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- New York Consortium for Evolutionary Primatology, New York, NY 10468, USA
| | - Chet C. Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USA
| | - Mary Ann Raghanti
- School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA
- Department of Anthropology, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
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6
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Lella E, Estrada E. Communicability distance reveals hidden patterns of Alzheimer's disease. Netw Neurosci 2020; 4:1007-1029. [PMID: 33195946 PMCID: PMC7655045 DOI: 10.1162/netn_a_00143] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/29/2020] [Indexed: 01/18/2023] Open
Abstract
The communicability distance between pairs of regions in human brain is used as a quantitative proxy for studying Alzheimer's disease. Using this distance, we obtain the shortest communicability path lengths between different regions of brain networks from patients with Alzheimer's disease (AD) and healthy cohorts (HC). We show that the shortest communicability path length is significantly better than the shortest topological path length in distinguishing AD patients from HC. Based on this approach, we identify 399 pairs of brain regions for which there are very significant changes in the shortest communicability path length after AD appears. We find that 42% of these regions interconnect both brain hemispheres, 28% connect regions inside the left hemisphere only, and 20% affect vermis connection with brain hemispheres. These findings clearly agree with the disconnection syndrome hypothesis of AD. Finally, we show that in 76.9% of damaged brain regions the shortest communicability path length drops in AD in relation to HC. This counterintuitive finding indicates that AD transforms the brain network into a more efficient system from the perspective of the transmission of the disease, because it drops the circulability of the disease factor around the brain regions in relation to its transmissibility to other regions.
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Affiliation(s)
- Eufemia Lella
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari, Italy
- Innovation Lab, Exprivia S.p.A., Molfetta, Italy
| | - Ernesto Estrada
- Institute of Applied Mathematics (IUMA), Universidad de Zaragoza, Zaragoza, Spain
- ARAID Foundation, Government of Aragón, Zaragoza, Spain
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7
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Stadterman J, Belthoff K, Han Y, Kadesh AD, Yoncheva Y, Roy AK. A Preliminary Investigation of the Effects of a Western Diet on Hippocampal Volume in Children. Front Pediatr 2020; 8:58. [PMID: 32195211 PMCID: PMC7062798 DOI: 10.3389/fped.2020.00058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 02/06/2020] [Indexed: 11/26/2022] Open
Abstract
Introduction: Over the course of the 20th century, there has been a sharp increase in the consumption of saturated fat and refined sugars. This so-called "western diet" (WD) has been extensively linked to biological alterations and associated functional deficits in the hippocampus of animals. However, the effects of a WD on the human hippocampus are less well-characterized. This preliminary study aimed to extend prior animal work by investigating the effects of a WD on hippocampal volume in children. Methods: Twenty-one healthy children (ages 5-9) completed a structural T1-weighted magnetic resonance imaging scan. Bilateral hippocampal volumes (as regions-of-interest) and bilateral amygdala volumes (as medial temporal lobe control regions-of-interest) were calculated. WD variables were derived from the parent-completed Youth/Adolescent Food Frequency Questionnaire. Specifically, variables were calculated as percent of daily calories consumed from sugars, fats, or a combination of these (WD). Results: While the relationships between overall WD consumption and bilateral hippocampal volumes were not significant, increased fat consumption was significantly related to decreased left hippocampal volume. Sugar consumption was not related to hippocampal size. Control region volumes were not related to any diet variables. Discussion: This study is the first to directly link diet-specifically fat consumption-to decreased left hippocampal volume in children. This extends previous work showing smaller left hippocampal volume related to obesity in pediatric samples. Though preliminary, findings represent an important step toward understanding the impact of diet on child brain development.
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Affiliation(s)
- Jill Stadterman
- Pediatric Emotion Regulation Lab, Department of Psychology, Fordham University, The Bronx, NY, United States
| | - Kyrstin Belthoff
- Pediatric Emotion Regulation Lab, Department of Psychology, Fordham University, The Bronx, NY, United States
| | - Ying Han
- Pediatric Emotion Regulation Lab, Department of Psychology, Fordham University, The Bronx, NY, United States
| | - Amanda D Kadesh
- Pediatric Emotion Regulation Lab, Department of Psychology, Fordham University, The Bronx, NY, United States
| | - Yuliya Yoncheva
- Department of Child and Adolescent Psychiatry, Hassenfeld Children's Hospital at New York University Langone Health, New York, NY, United States
| | - Amy Krain Roy
- Pediatric Emotion Regulation Lab, Department of Psychology, Fordham University, The Bronx, NY, United States.,Department of Child and Adolescent Psychiatry, Hassenfeld Children's Hospital at New York University Langone Health, New York, NY, United States
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8
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Munger EL, Edler MK, Hopkins WD, Ely JJ, Erwin JM, Perl DP, Mufson EJ, Hof PR, Sherwood CC, Raghanti MA. Astrocytic changes with aging and Alzheimer's disease-type pathology in chimpanzees. J Comp Neurol 2019; 527:1179-1195. [PMID: 30578640 PMCID: PMC6401278 DOI: 10.1002/cne.24610] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/20/2018] [Accepted: 12/01/2018] [Indexed: 01/01/2023]
Abstract
Astrocytes are the main homeostatic cell of the central nervous system. In addition, astrocytes mediate an inflammatory response when reactive to injury or disease known as astrogliosis. Astrogliosis is marked by an increased expression of glial fibrillary acidic protein (GFAP) and cellular hypertrophy. Some degree of astrogliosis is associated with normal aging and degenerative conditions such as Alzheimer's disease (AD) and other dementing illnesses in humans. The recent observation of pathological markers of AD (amyloid plaques and neurofibrillary tangles) in aged chimpanzee brains provided an opportunity to examine the relationships among aging, AD-type pathology, and astrocyte activation in our closest living relatives. Stereologic methods were used to quantify GFAP-immunoreactive astrocyte density and soma volume in layers I, III, and V of the prefrontal and middle temporal cortex, as well as in hippocampal fields CA1 and CA3. We found that the patterns of astrocyte activation in the aged chimpanzee brain are distinct from humans. GFAP expression does not increase with age in chimpanzees, possibly indicative of lower oxidative stress loads. Similar to humans, chimpanzee layer I astrocytes in the prefrontal cortex are susceptible to AD-like changes. Both prefrontal cortex layer I and hippocampal astrocytes exhibit a high degree of astrogliosis that is positively correlated with accumulation of amyloid beta and tau proteins. However, unlike humans, chimpanzees do not display astrogliosis in other cortical layers. These results demonstrate a unique pattern of cortical aging in chimpanzees and suggest that inflammatory processes may differ between humans and chimpanzees in response to pathology.
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Affiliation(s)
- Emily L. Munger
- Department of Anthropology and School of Biomedical Sciences, Kent State University, Kent, Ohio
| | - Melissa K. Edler
- Department of Anthropology and School of Biomedical Sciences, Kent State University, Kent, Ohio,Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, Ohio
| | - William D. Hopkins
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center, Atlanta, Georgia
| | | | - Joseph M. Erwin
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, District of Columbia
| | - Daniel P. Perl
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Elliott J. Mufson
- Departments of Neurobiology and Neurology, Barrow Neurological Institute, Phoenix, Arizona
| | - Patrick R. Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York,New York Consortium in Evolutionary Primatology, New York, New York
| | - Chet C. Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, District of Columbia
| | - Mary Ann Raghanti
- Department of Anthropology and School of Biomedical Sciences, Kent State University, Kent, Ohio
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9
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Parahippocampal gyrus expression of endothelial and insulin receptor signaling pathway genes is modulated by Alzheimer's disease and normalized by treatment with anti-diabetic agents. PLoS One 2018; 13:e0206547. [PMID: 30383799 PMCID: PMC6211704 DOI: 10.1371/journal.pone.0206547] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/15/2018] [Indexed: 12/14/2022] Open
Abstract
A large body of literature links risk of cognitive decline, mild cognitive impairment (MCI) and dementia with Type 2 Diabetes (T2D) or pre-diabetes. Accumulating evidence implicates a close relationship between the brain insulin receptor signaling pathway (IRSP) and the accumulation of amyloid beta and hyperphosphorylated and conformationally abnormal tau. We showed previously that the neuropathological features of Alzheimer's disease (AD were reduced in patients with diabetes who were treated with insulin and oral antidiabetic medications. To understand better the neurobiological substrates of T2D and T2D medications in AD, we examined IRSP and endothelial cell markers in the parahippocampal gyrus of controls (N = 30), of persons with AD (N = 19), and of persons with AD and T2D, who, in turn, had been treated with anti-diabetic drugs (insulin and or oral agents; N = 34). We studied the gene expression of selected members of the IRSP and selective endothelial cell markers in bulk postmortem tissue from the parahippocampal gyrus and in endothelial cell enriched isolates from the same brain region. The results indicated that there are considerable abnormalities and reductions in gene expression (bulk tissue homogenates and endothelial cell isolates) in the parahippocampal gyri of persons with AD that map directly to genes associated with the microvasculature and the IRSP. Our results also showed that the numbers of abnormally expressed microvasculature and IRSP associated genes in diabetic AD donors who had been treated with anti-diabetic agents were reduced significantly. These findings suggest that anti-diabetic treatments may reduce or normalize compromised microvascular and IRSP functions in AD.
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10
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Sanchez-Rodriguez LM, Iturria-Medina Y, Baines EA, Mallo SC, Dousty M, Sotero RC. Design of optimal nonlinear network controllers for Alzheimer's disease. PLoS Comput Biol 2018; 14:e1006136. [PMID: 29795548 PMCID: PMC5967700 DOI: 10.1371/journal.pcbi.1006136] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 04/12/2018] [Indexed: 12/26/2022] Open
Abstract
Brain stimulation can modulate the activity of neural circuits impaired by Alzheimer’s disease (AD), having promising clinical benefit. However, all individuals with the same condition currently receive identical brain stimulation, with limited theoretical basis for this generic approach. In this study, we introduce a control theory framework for obtaining exogenous signals that revert pathological electroencephalographic activity in AD at a minimal energetic cost, while reflecting patients’ biological variability. We used anatomical networks obtained from diffusion magnetic resonance images acquired by the Alzheimer’s Disease Neuroimaging Initiative (ADNI) as mediators for the interaction between Duffing oscillators. The nonlinear nature of the brain dynamics is preserved, given that we extend the so-called state-dependent Riccati equation control to reflect the stimulation objective in the high-dimensional neural system. By considering nonlinearities in our model, we identified regions for which control inputs fail to correct abnormal activity. There are changes to the way stimulated regions are ranked in terms of the energetic cost of controlling the entire network, from a linear to a nonlinear approach. We also found that limbic system and basal ganglia structures constitute the top target locations for stimulation in AD. Patients with highly integrated anatomical networks–namely, networks having low average shortest path length, high global efficiency–are the most suitable candidates for the propagation of stimuli and consequent success on the control task. Other diseases associated with alterations in brain dynamics and the self-control mechanisms of the brain can be addressed through our framework. This work aims to close the knowledge gap between theory and experiment in brain stimulation. Previous modeling approaches for stimulation have overlooked the nonlinear dynamical nature of the brain and failed to shed light on efficient mechanisms for the exogenous control of the brain. Amid the current efforts for developing personalized medicine, we introduce a framework for producing tailored stimulation signals, based on individual neuroimaging data and innovative modeling. This is the first time, to our knowledge, that brain stimulation for the most common cause of dementia, Alzheimer’s disease, is theoretically addressed. Our approach leads to the identification of potential target regions and subjects to successfully respond to brain stimulation therapies and yields various disease-reverting signals. Although focused on Alzheimer’s in this study, our methodology could be applied to other clinical conditions characterized by abnormalities in brain dynamics, like epilepsy and Parkinson’s, the treatment of which can benefit from the use of optimal control strategies.
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Affiliation(s)
- Lazaro M. Sanchez-Rodriguez
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- * E-mail: (LMSR); (RCS)
| | - Yasser Iturria-Medina
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Quebec, Canada
| | - Erica A. Baines
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Sabela C. Mallo
- Departament of Developmental Psychology, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Mehdy Dousty
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Roberto C. Sotero
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- * E-mail: (LMSR); (RCS)
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11
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Cerebral changes and disrupted gray matter cortical networks in asymptomatic older adults at risk for Alzheimer's disease. Neurobiol Aging 2018; 64:58-67. [DOI: 10.1016/j.neurobiolaging.2017.12.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 11/26/2017] [Accepted: 12/12/2017] [Indexed: 12/18/2022]
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12
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Edler MK, Sherwood CC, Meindl RS, Hopkins WD, Ely JJ, Erwin JM, Mufson EJ, Hof PR, Raghanti MA. Aged chimpanzees exhibit pathologic hallmarks of Alzheimer's disease. Neurobiol Aging 2017; 59:107-120. [PMID: 28888720 PMCID: PMC6343147 DOI: 10.1016/j.neurobiolaging.2017.07.006] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 07/13/2017] [Accepted: 07/15/2017] [Indexed: 11/26/2022]
Abstract
Alzheimer's disease (AD) is a uniquely human brain disorder characterized by the accumulation of amyloid-beta protein (Aβ) into extracellular plaques, neurofibrillary tangles (NFT) made from intracellular, abnormally phosphorylated tau, and selective neuronal loss. We analyzed a large group of aged chimpanzees (n = 20, age 37-62 years) for evidence of Aβ and tau lesions in brain regions affected by AD in humans. Aβ was observed in plaques and blood vessels, and tau lesions were found in the form of pretangles, NFT, and tau-immunoreactive neuritic clusters. Aβ deposition was higher in vessels than in plaques and correlated with increases in tau lesions, suggesting that amyloid build-up in the brain's microvasculature precedes plaque formation in chimpanzees. Age was correlated to greater volumes of Aβ plaques and vessels. Tangle pathology was observed in individuals that exhibited plaques and moderate or severe cerebral amyloid angiopathy, a condition in which amyloid accumulates in the brain's vasculature. Amyloid and tau pathology in aged chimpanzees suggests these AD lesions are not specific to the human brain.
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Affiliation(s)
- Melissa K Edler
- School of Biomedical Sciences, Kent State University, Kent, OH, USA; Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA.
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC, USA
| | - Richard S Meindl
- Department of Anthropology, Kent State University, Kent, OH, USA
| | - William D Hopkins
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center, Atlanta, GA, USA; Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | | | - Joseph M Erwin
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC, USA
| | - Elliott J Mufson
- Departments of Neurobiology and Neurology, Barrow Neurological Institute, Phoenix, AZ, USA
| | - Patrick R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA; New York Consortium for Evolutionary Primatology, New York, NY, USA
| | - Mary Ann Raghanti
- School of Biomedical Sciences, Kent State University, Kent, OH, USA; Department of Anthropology, Kent State University, Kent, OH, USA
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13
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Brain metabolic correlates of CSF Tau protein in a large cohort of Alzheimer's disease patients: A CSF and FDG PET study. Brain Res 2017; 1678:116-122. [PMID: 29066367 DOI: 10.1016/j.brainres.2017.10.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 10/04/2017] [Accepted: 10/16/2017] [Indexed: 11/23/2022]
Abstract
AIMS Physiopathological mechanisms of Alzheimer's disease (AD) are still matter of debate. Especially the role of amyloid β and tau pathology in the development of the disease are still matter of debate. Changes in tau and amyloid β peptide concentration in cerebrospinal fluid (CSF) and hypometabolic patterns at fluorine-18 fluorodeoxyglucose (18F-FDG) PET scanning are considered as biomarkers of AD. The present study was aimed to evaluate the relationships between the concentrations of CSF total Tau (t-Tau), phosphorilated Tau (p-Tau) and Aβ1-42 amyloid peptide with 18F-FDG brain distribution in a group of patients with AD. MATERIALS AND METHODS We examined 131 newly diagnosed AD patients according to the NINCDS-ADRDA criteria and 20 healthy controls. The mean (±SD) age of the patients was 70 (±7) years; 57 were male and 74 were female. All patients and controls underwent a complete clinical investigation, including medical history, neurological examination, mini-mental state examination (MMSE), a complete blood screening (including routine exams, thyroid hormones and a complete neuropsychological evaluation). Structural MRI was performed not earlier than 1 month before the 18F-FDG PET/CT. The following patients were excluded: those with isolated deficits and/or unmodified MMSE (=25/30) on revisit (period of follow-up: 6, 12 and 18 months); patients who had had a clinically manifest acute stroke in the last 6 months with a Hachinsky score greater than 4; and patients with radiological evidence of subcortical lesions. All AD patients were taken off cholinesterase inhibitor treatment throughout the study. We performed lumbar puncture and CSF sampling for diagnostic purposes 2 weeks (±2 days) before the PET/CT scan. The relationship between brain F-FDG uptake and CSF biomarkers was analysed using statistical parametric mapping (SPM8; Wellcome Department of Cognitive Neurology, London, UK) implemented in Matlab R2012b using the MMSE score, sex and age, and other CSF biomarkers as covariates. RESULTS t-Tau, p-Tau and Aβ(1-42) in CSF resulted 774 ± 345 pg/ml, 98 ± 64 pg/ml and 348.8 ± 111 pg/ml respectively. SPM analysis showed a significant negative correlation between CSF t-Tau and 18F FDG uptake in right temporal, parietal and frontal lobe (Brodmann areas, BA, 20, 40 and 8; P fdr and few corr < 0.001, ke 19534). We did not find any significant relationships with other CSF biomarkers. CONCLUSIONS t-Tau deposition in brain is related to temporal, parietal and frontal hypometabolism in AD.
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Cortical laminar tau deposits and activated astrocytes in Alzheimer's disease visualised by 3H-THK5117 and 3H-deprenyl autoradiography. Sci Rep 2017; 7:45496. [PMID: 28374768 PMCID: PMC5379625 DOI: 10.1038/srep45496] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 03/01/2017] [Indexed: 11/13/2022] Open
Abstract
Hyperphosphorylated tau protein deposits and, inflammatory processes are characteristic components of Alzheimer disease (AD) pathology. We here aimed to visualize in vitro the distribution of tau deposits and activated astrocytes across the cortical layers in autopsy AD brain tissue using the radiotracers 3H-THK5117 and 3H-deprenyl. 3H-THK5117 and 3H-deprenyl autoradiographies were carried out on frozen brain sections from three AD patients and one healthy control. 3H-THK5117 showed a distinct laminar cortical binding similar to 3H-deprenyl autoradiography, with an extensive binding in the superficial and deep layers of the temporal neocortices, whereas the middle frontal gyrus showed an even binding throughout the layers. Globally, eventhough some differences could be observed, AT8 (tau) and GFAP (astrocyte) immunostaining showed a laminar pattern comparable to their corresponding radiotracers within each AD case. Some variability was observed between the AD cases reflecting differences in disease phenotype. The similar laminar cortical brain distribution of tau deposits and activated astrocytes supports the hypothesis of a close pathological interconnection. The difference in regional binding patterns of 3H-THK5117 and AT8 antibody staining suggest additional tau binding sites detectable by 3H-THK5117.
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(1)H-MRS asymmetry changes in the anterior and posterior cingulate gyrus in patients with mild cognitive impairment and mild Alzheimer's disease. Compr Psychiatry 2016; 69:179-85. [PMID: 27423359 DOI: 10.1016/j.comppsych.2016.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/13/2016] [Accepted: 06/04/2016] [Indexed: 11/20/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia worldwide. Amnestic mild cognitive impairment (aMCI) is often the prodromal stage to AD. Most patients with aMCI harbor the pathologic changes of AD and demonstrate transition to AD at a rate of 10%-15% per year. Patients with AD and aMCI experience progressive brain metabolite changes. Accumulating evidence indicates that the asymmetry changes of left and right brain happen in the early stage of AD. However, the features of asymmetry changes in both anterior cingulate gyrus (ACG) and posterior cingulate gyrus (PCG) are still unclear. Here, we examine the left-right asymmetry changes of metabolites in ACG and PCG. Fifteen cases of mild AD patients meeting criteria for probable AD of NINDS-ADRDA, thirteen cases of aMCI according to the Mayo Clinic Alzheimer's Disease Research Center criteria, and sixteen cases of age-matched normal controls (NC) received Proton magnetic resonance spectroscopy ((1)H-MRS) for measurement of NAA/mI, NAA/Cr, Cho/Cr, and mI/Cr ratios in the PCG and ACG bilaterally. We analyzed (1)H-MRS data by paired t-test to validate the left-right asymmetry of (1)H-MRS data in the PCG and ACG. In AD, there was a significant difference in mI/Cr between the left and right ACG (P<0.001) and the left and right PCG (P=0.007). In aMCI, there was a significant difference in mI/Cr between the left and right ACG (P<0.001). In NC, there were no differences in the ratio value of metabolites NAA/mI, NAA/Cr, Cho/Cr, and mI/Cr between the left and right ACG and PCG. Thus, the left-right asymmetry of mI/Cr in the ACG and PCG may be an important biological indicator of mild AD.
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Jacka FN, Cherbuin N, Anstey KJ, Sachdev P, Butterworth P. Western diet is associated with a smaller hippocampus: a longitudinal investigation. BMC Med 2015; 13:215. [PMID: 26349802 PMCID: PMC4563885 DOI: 10.1186/s12916-015-0461-x] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/25/2015] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Recent meta-analyses confirm a relationship between diet quality and both depression and cognitive health in adults. While the biological pathways that underpin these relationships are likely multitudinous, extensive evidence from animal studies points to the involvement of the hippocampus. The aim of this study was to examine the association between dietary patterns and hippocampal volume in humans, and to assess whether diet was associated with differential rates of hippocampal atrophy over time. METHODS Data were drawn from the Personality and Total Health Through Life Study and focused on a subsample of the cohort (n = 255) who were aged 60-64 years at baseline in 2001, completed a food frequency questionnaire, and underwent two magnetic resonance imaging scans approximately 4 years apart. Longitudinal generalized estimating equation linear regression models were used to assess the association between dietary factors and left and right hippocampal volumes over time. RESULTS Every one standard deviation increase in healthy "prudent" dietary pattern was associated with a 45.7 mm(3) (standard error 22.9 mm(3)) larger left hippocampal volume, while higher consumption of an unhealthy "Western" dietary pattern was (independently) associated with a 52.6 mm(3) (SE 26.6 mm(3)) smaller left hippocampal volume. These relationships were independent of covariates including age, gender, education, labour-force status, depressive symptoms and medication, physical activity, smoking, hypertension and diabetes. While hippocampal volume declined over time, there was no evidence that dietary patterns influenced this decline. No relationships were observed between dietary patterns and right hippocampal volume. CONCLUSIONS Lower intakes of nutrient-dense foods and higher intakes of unhealthy foods are each independently associated with smaller left hippocampal volume. To our knowledge, this is the first human study to demonstrate associations between diet and hippocampal volume concordant with data previously observed in animal models.
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Affiliation(s)
- Felice N Jacka
- Division of Nutritional Psychiatry Research, IMPACT Strategic Research Centre, Deakin University, Geelong, Australia. .,Department of Psychiatry, The University of Melbourne, Melbourne, Australia. .,Centre for Adolescent Health, Murdoch Children's Research Institute, Melbourne, Australia. .,Black Dog Institute, Sydney, Australia.
| | - Nicolas Cherbuin
- Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, The Australian National University, Canberra, Australia.
| | - Kaarin J Anstey
- Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, The Australian National University, Canberra, Australia.
| | - Perminder Sachdev
- Centre for Healthy Brain Ageing (CHeBA), School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, Australia.
| | - Peter Butterworth
- Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, The Australian National University, Canberra, Australia.
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Cherbuin N, Sargent-Cox K, Easteal S, Sachdev P, Anstey KJ. Hippocampal atrophy is associated with subjective memory decline: The PATH Through Life study. Am J Geriatr Psychiatry 2015; 23:446-55. [PMID: 25204687 DOI: 10.1016/j.jagp.2014.07.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 07/04/2014] [Accepted: 07/21/2014] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To investigate whether subjective memory decline (SMD) in cognitively healthy individuals is associated with hippocampal atrophy. METHODS Multiple regression analyses assessing the relationship between hippocampal atrophy over 4 years and SMD at baseline and follow-up in 305 cognitively healthy individuals aged 60-64 years free from dementia, mild cognitive impairment, and other neurological disorders. RESULTS SMD at baseline was not a significant predictor of hippocampal atrophy. However, SMD at follow-up was associated with greater hippocampal atrophy. Associations were reduced but remained significant after controlling for anxiety and depression symptomatology. CONCLUSION Hippocampal atrophy was associated with incident/persisting SMD and this association was not, or only partly, explained by anxiety and depression symptomatology. These results are consistent with a biological origin to subjective memory decline. SMD should be included in screening and neuropsychological batteries.
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Affiliation(s)
- Nicolas Cherbuin
- Centre for Research on Ageing, Health and Wellbeing, Australian National University, Canberra, Australia.
| | - Kerry Sargent-Cox
- Centre for Research on Ageing, Health and Wellbeing, Australian National University, Canberra, Australia
| | - Simon Easteal
- John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Perminder Sachdev
- School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Kaarin J Anstey
- Centre for Research on Ageing, Health and Wellbeing, Australian National University, Canberra, Australia
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Abstract
Whether mild cognitive impairment (MCI) has a distinct neuropathological profile that reflects an intermediate state between no cognitive impairment and dementia is not clear. Identifying which biological events occur at the earliest stage of progressive disease and which are secondary to the neuropathological process is important for understating pathological pathways and for targeted disease prevention. Many studies have now reported on the neurobiology of this intermediate stage. In this systematic review, we synthesize current evidence on the neuropathological profile of MCI. A total of 162 studies were identified with varied definition of MCI, settings ranging from population to specialist clinics and a wide range of objectives. From these studies, it is clear that MCI is neuropathologically complex and cannot be understood within a single framework. Pathological changes identified include plaque and tangle formation, vascular pathologies, neurochemical deficits, cellular injury, inflammation, oxidative stress, mitochondrial changes, changes in genomic activity, synaptic dysfunction, disturbed protein metabolism and disrupted metabolic homeostasis. Determining which factors primarily drive neurodegeneration and dementia and which are secondary features of disease progression still requires further research. Standardization of the definition of MCI and reporting of pathology would greatly assist in building an integrated picture of the clinical and neuropathological profile of MCI.
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Poza J, Gómez C, Bachiller A, Hornero R. Spectral and Non-Linear Analyses of Spontaneous Magnetoencephalographic Activity in Alzheimer's Disease. JOURNAL OF HEALTHCARE ENGINEERING 2012. [DOI: 10.1260/2040-2295.3.2.299] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Foster PP, Rosenblatt KP, Kuljiš RO. Exercise-induced cognitive plasticity, implications for mild cognitive impairment and Alzheimer's disease. Front Neurol 2011; 2:28. [PMID: 21602910 PMCID: PMC3092070 DOI: 10.3389/fneur.2011.00028] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 04/18/2011] [Indexed: 12/17/2022] Open
Abstract
Lifestyle factors such as intellectual stimulation, cognitive and social engagement, nutrition, and various types of exercise appear to reduce the risk for common age-associated disorders such as Alzheimer’s disease (AD) and vascular dementia. In fact, many studies have suggested that promoting physical activity can have a protective effect against cognitive deterioration later in life. Slowing or a deterioration of walking speed is associated with a poor performance in tests assessing psychomotor speed and verbal fluency in elderly individuals. Fitness training influences a wide range of cognitive processes, and the largest positive impact observed is for executive (a.k.a. frontal lobe) functions. Studies show that exercise improves additional cognitive functions such as tasks mediated by the hippocampus, and result in major changes in plasticity in the hippocampus. Interestingly, this exercise-induced plasticity is also pronounced in APOE ε4 carriers who express a risk factor for late-onset AD that may modulate the effect of treatments. Based on AD staging by Braak and Braak (1991) and Braak et al. (1993) we propose that the effects of exercise occur in two temporo-spatial continua of events. The “inward” continuum from isocortex (neocortex) to entorhinal cortex/hippocampus for amyloidosis and a reciprocal “outward” continuum for neurofibrillary alterations. The exercise-induced hypertrophy of the hippocampus at the core of these continua is evaluated in terms of potential for prevention to stave off neuronal degeneration. Exercise-induced production of growth factors such as the brain-derived neurotrophic factor (BDNF) has been shown to enhance neurogenesis and to play a key role in positive cognitive effects. Insulin-like growth factor (IGF-1) may mediate the exercise-induced response to exercise on BDNF, neurogenesis, and cognitive performance. It is also postulated to regulate brain amyloid β (Aβ) levels by increased clearance via the choroid plexus. Growth factors, specifically fibroblast growth factor and IGF-1 receptors and/or their downstream signaling pathways may interact with the Klotho gene which functions as an aging suppressor gene. Neurons may not be the only cells affected by exercise. Glia (astrocytes and microglia), neurovascular units and the Fourth Element may also be affected in a differential fashion by the AD process. Analyses of these factors, as suggested by the multi-dimensional matrix approach, are needed to improve our understanding of this complex multi-factorial process, which is increasingly relevant to conquering the escalating and intersecting world-wide epidemics of dementia, diabetes, and sarcopenia that threaten the global healthcare system. Physical activity and interventions aimed at enhancing and/or mimicking the effects of exercise are likely to play a significant role in mitigating these epidemics, together with the embryonic efforts to develop cognitive rehabilitation for neurodegenerative disorders.
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Affiliation(s)
- Philip P Foster
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Texas Medical Branch Galveston, TX, USA
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Latha R, Daisy P. Influence of Terminalia bellerica Roxb. Fruit Extracts on Biochemical
Parameters in Streptozotocin Diabetic Rats. INT J PHARMACOL 2010. [DOI: 10.3923/ijp.2010.89.96] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Cherbuin N, Réglade-Meslin C, Kumar R, Sachdev P, Anstey KJ. Mild Cognitive Disorders are Associated with Different Patterns of Brain asymmetry than Normal Aging: The PATH through Life Study. Front Psychiatry 2010; 1:11. [PMID: 21423423 PMCID: PMC3059654 DOI: 10.3389/fpsyt.2010.00011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 04/07/2010] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Defining how brain structures differ in pre-clinical dementia is important to better understand the pathological processes involved and to inform clinical practice. The aim of this study was to identify significant brain correlates (volume and asymmetry in volume) of mild cognitive disorders when compared to normal controls in a large community-based sample of young-old individuals who were assessed for cognitive impairment. METHODS Cortical and sub-cortical volumes were measured using a semi-automated method in 398 participants aged 64-70 years who were selected from a larger randomly sampled cohort and who agreed to undergo an MRI scan. Diagnoses were reached based on established protocols for MCI and a more inclusive category of any Mild Cognitive Disorder (any-MCD: which includes AAMI, AACD, OCD, MNC, CDR, MCI). Logistic regression analyses were used to assess the relationship between volume and asymmetry of theoretically relevant cerebral structures (predictors) and MCI or any-MCD while controlling for age, sex, and intra-cranial volume. RESULTS The main correlates of cognitive impairment assessed in multivariate analyses were hippocampal asymmetry (more to left, MCI: OR 0.83, 95%CI 0.71-0.96, p = 0.013; MCD: OR 0.86, 95%CI 0.77-0.97, p = 0.011), lateral ventricle asymmetry (more to left, MCI: OR 0.95, 95%CI 0.91-0.99, p = 0.009; MCD: OR 0.95, 95%CI 0.92-0.98, p = 0.004), and cerebellar cortex asymmetry (more to right, MCI: OR 1.51, 95%CI 1.13-2.01, p = 0.005). CONCLUSIONS In this population-based cohort stronger associations were found between asymmetry measures, rather than raw volumes in cerebral structures, and mild cognitive disorders.
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Affiliation(s)
- Nicolas Cherbuin
- Centre for Mental Health Research, Australian National University Canberra, ACT, Australia
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