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Sheikh-Bahaei N, Chen M, Pappas I. Magnetic Resonance Spectroscopy (MRS) in Alzheimer's Disease. Methods Mol Biol 2024; 2785:115-142. [PMID: 38427192 DOI: 10.1007/978-1-0716-3774-6_9] [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: 03/02/2024]
Abstract
MRS is a noninvasive technique to measure different metabolites in the brain. Changes in the levels of certain metabolites can be used as surrogate markers for Alzheimer's disease. They can potentially be used for diagnosis, prediction of prognosis, or even assessing response to treatment.There are different techniques for MRS acquisitions including STimulated Echo Acquisition Mode (STEAM) and Point Resolved Spectroscopy (PRESS). In terms of localization, single or multi-voxel methods can be used. Based on current data: 1. NAA, marker of neuronal integrity and viability, reduces in AD with longitudinal changes over the time as the disease progresses. There are data claiming that reduction of NAA is associated with tau accumulation, early neurodegenerative processes, and cognitive decline. Therefore, it can be used as a stage biomarker for AD to assess the severity of the disease. With advancement of disease modifying therapies, there is a potential role for NAA in the future to be used as a marker of response to treatment. 2. mI, marker of glial cell proliferation and activation, is associated with AB pathology and has early changes in the course of the disease. The NAA/mI ratio can be predictive of AD development with high specificity and can be utilized in the clinical setting to stratify cases for further evaluation with PET for potential treatments. 3. The changes in the level of other metabolites such as Chol, Glu, Gln, and GABA are controversial because of the lack of standardization of MRS techniques, current technical limitations, and possible region specific changes. 4. Ultrahigh field MRS and more advanced techniques can overcome many of these limitations and enable us to measure more metabolites with higher accuracy. 5. Standardization of MRS techniques, validation of metabolites' changes against PET using PET-guided technique, and longitudinal follow-ups to investigate the temporal changes of the metabolites in relation to other biomarkers and cognition will be crucial to confirm the utility of MRS as a potential noninvasive biomarker for AD.
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Affiliation(s)
- Nasim Sheikh-Bahaei
- Department of Radiology, Keck School of Medicine of USC, Los Angeles, CA, USA.
| | - Michelle Chen
- Keck School of Medicine of USC, USC, Los Angeles, CA, USA
| | - Ioannis Pappas
- USC Mark and Mary Stevens Neuroimaging and Informatics Institute, USC, Los Angeles, CA, USA
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2
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Chronic lead exposure disrupts neurometabolic activity in mouse brain: An ex vivo 1H-[ 13C]-NMR study. Neurotoxicology 2023; 94:117-125. [PMID: 36368548 DOI: 10.1016/j.neuro.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 10/21/2022] [Accepted: 11/06/2022] [Indexed: 11/09/2022]
Abstract
Lead poisoning has been identified as a problem in adults as well as in children. Chronic exposure to lead has been implicated in neurological disorders such as amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. In the present study, we evaluated the impact of chronic lead exposure on cerebral glutamatergic and GABAergic metabolic activity in mice. C57BL6 mice were provided lead acetate in drinking water for two months. The regional cerebral metabolic activity was measured using 1H-[13C]-NMR spectroscopy in conjunction with infusion of [1,6-13C2]glucose. The blood Pb2+ increased significantly in lead acetate treated mice. Concomitantly, there was a significant reduction in the forelimb strength. The level of myo-inositol was elevated in the cerebral cortex of mice chronically exposed to lead. The glutamatergic neurometabolic activity was found to be reduced following chronic lead exposure in the cerebral cortex, hippocampus, and striatum. In contrast, the GABAergic fluxes were impaired in the hippocampus and thalamus only. The metabolic fluxes in the cerebellum were unperturbed to Pb2+ toxicity. In conclusion, we report that chronic lead exposure in mice leads to an impairment in forelimb strength, and a perturbation in neurometabolism in brain regions involving cognition and movement.
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3
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Bakhshi S, Tehrani-Doost M, Batouli SAH. Evaluation of fronto-cerebellar neurometabolites in youth with ADHD compared to the healthy group and their associations with cognitive and behavioral characteristics: A proton magnetic spectroscopy study. Int J Psychophysiol 2022; 182:190-199. [DOI: 10.1016/j.ijpsycho.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022]
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4
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Probert F, Yeo T, Zhou Y, Sealey M, Arora S, Palace J, Claridge TDW, Hillenbrand R, Oechtering J, Leppert D, Kuhle J, Anthony DC. Integrative biochemical, proteomics and metabolomics cerebrospinal fluid biomarkers predict clinical conversion to multiple sclerosis. Brain Commun 2021; 3:fcab084. [PMID: 33997784 PMCID: PMC8111065 DOI: 10.1093/braincomms/fcab084] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 12/23/2022] Open
Abstract
Eighty-five percent of multiple sclerosis cases begin with a discrete attack termed clinically isolated syndrome, but 37% of clinically isolated syndrome patients do not experience a relapse within 20 years of onset. Thus, the identification of biomarkers able to differentiate between individuals who are most likely to have a second clinical attack from those who remain in the clinically isolated syndrome stage is essential to apply a personalized medicine approach. We sought to identify biomarkers from biochemical, metabolic and proteomic screens that predict clinically defined conversion from clinically isolated syndrome to multiple sclerosis and generate a multi-omics-based algorithm with higher prognostic accuracy than any currently available test. An integrative multi-variate approach was applied to the analysis of cerebrospinal fluid samples taken from 54 individuals at the point of clinically isolated syndrome with 2-10 years of subsequent follow-up enabling stratification into clinical converters and non-converters. Leukocyte counts were significantly elevated at onset in the clinical converters and predict the occurrence of a second attack with 70% accuracy. Myo-inositol levels were significantly increased in clinical converters while glucose levels were decreased, predicting transition to multiple sclerosis with accuracies of 72% and 63%, respectively. Proteomics analysis identified 89 novel gene products related to conversion. The identified biochemical and protein biomarkers were combined to produce an algorithm with predictive accuracy of 83% for the transition to clinically defined multiple sclerosis, outperforming any individual biomarker in isolation including oligoclonal bands. The identified protein biomarkers are consistent with an exaggerated immune response, perturbed energy metabolism and multiple sclerosis pathology in the clinical converter group. The new biomarkers presented provide novel insight into the molecular pathways promoting disease while the multi-omics algorithm provides a means to more accurately predict whether an individual is likely to convert to clinically defined multiple sclerosis.
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Affiliation(s)
- Fay Probert
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.,Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK
| | - Tianrong Yeo
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.,Department of Neurology, National Neuroscience Institute, Singapore 308437, Singapore
| | - Yifan Zhou
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Megan Sealey
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Siddharth Arora
- Mathematical Institute, University of Oxford, Oxford OX2 6GG, UK
| | - Jacqueline Palace
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | | | | | - Johanna Oechtering
- Neurology, Departments of Medicine, Clinical Research and Biomedicine, University Hospital Basel, University of Basel, Basel CH-4031, Switzerland
| | - David Leppert
- Neurology, Departments of Medicine, Clinical Research and Biomedicine, University Hospital Basel, University of Basel, Basel CH-4031, Switzerland
| | - Jens Kuhle
- Neurology, Departments of Medicine, Clinical Research and Biomedicine, University Hospital Basel, University of Basel, Basel CH-4031, Switzerland
| | - Daniel C Anthony
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
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5
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Haley AP, Oleson S, Pasha E, Birdsill A, Kaur S, Thompson J, Tanaka H. Phenotypic heterogeneity of obesity-related brain vulnerability: one-size interventions will not fit all. Ann N Y Acad Sci 2018; 1428:89-102. [PMID: 29741211 DOI: 10.1111/nyas.13673] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 02/10/2018] [Accepted: 02/17/2018] [Indexed: 01/07/2023]
Abstract
Intact memory and problem solving are key to functional independence and quality of life in older age. Considering the unprecedented demographic shift toward a greater number of older adults than children in the United States in the next few decades, it is critically important for older adults to maintain work productivity and functional independence for as long as possible. Implementing early interventions focused on modifiable risk factors for cognitive decline at midlife is a strategy with the highest chance of success at present, bearing in mind the current lack of dementia cures. We present a selective, narrative review of evidence linking nutrition, body composition, vascular health, and brain function in midlife to highlight the phenotypic heterogeneity of obesity-related brain vulnerability and to endorse the development of individually tailored lifestyle modification plans for primary prevention of cognitive decline.
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Affiliation(s)
- Andreana P Haley
- Department of Psychology, The University of Texas at Austin, Austin, Texas.,Imaging Research Center, The University of Texas at Austin, Austin, Texas
| | - Stephanie Oleson
- Department of Psychology, The University of Texas at Austin, Austin, Texas
| | - Evan Pasha
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas
| | - Alex Birdsill
- Department of Psychology, The University of Texas at Austin, Austin, Texas
| | - Sonya Kaur
- Department of Psychology, The University of Texas at Austin, Austin, Texas
| | - Janelle Thompson
- Department of Psychology, The University of Texas at Austin, Austin, Texas
| | - Hirofumi Tanaka
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas
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6
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Janova H, Arinrad S, Balmuth E, Mitjans M, Hertel J, Habes M, Bittner RA, Pan H, Goebbels S, Begemann M, Gerwig UC, Langner S, Werner HB, Kittel-Schneider S, Homuth G, Davatzikos C, Völzke H, West BL, Reif A, Grabe HJ, Boretius S, Ehrenreich H, Nave KA. Microglia ablation alleviates myelin-associated catatonic signs in mice. J Clin Invest 2018; 128:734-745. [PMID: 29252214 PMCID: PMC5785265 DOI: 10.1172/jci97032] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/07/2017] [Indexed: 12/21/2022] Open
Abstract
The underlying cellular mechanisms of catatonia, an executive "psychomotor" syndrome that is observed across neuropsychiatric diseases, have remained obscure. In humans and mice, reduced expression of the structural myelin protein CNP is associated with catatonic signs in an age-dependent manner, pointing to the involvement of myelin-producing oligodendrocytes. Here, we showed that the underlying cause of catatonic signs is the low-grade inflammation of white matter tracts, which marks a final common pathway in Cnp-deficient and other mutant mice with minor myelin abnormalities. The inhibitor of CSF1 receptor kinase signaling PLX5622 depleted microglia and alleviated the catatonic symptoms of Cnp mutants. Thus, microglia and low-grade inflammation of myelinated tracts emerged as the trigger of a previously unexplained mental condition. We observed a very high (25%) prevalence of individuals with catatonic signs in a deeply phenotyped schizophrenia sample (n = 1095). Additionally, we found the loss-of-function allele of a myelin-specific gene (CNP rs2070106-AA) associated with catatonia in 2 independent schizophrenia cohorts and also associated with white matter hyperintensities in a general population sample. Since the catatonic syndrome is likely a surrogate marker for other executive function defects, we suggest that microglia-directed therapies may be considered in psychiatric disorders associated with myelin abnormalities.
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Affiliation(s)
- Hana Janova
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Sahab Arinrad
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Evan Balmuth
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Marina Mitjans
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Johannes Hertel
- Department of Psychiatry and Psychotherapy, University Medicine, and German Center for Neurodegenerative Diseases (DZNE), Greifswald, Germany
| | - Mohamad Habes
- Department of Psychiatry and Psychotherapy, University Medicine, and German Center for Neurodegenerative Diseases (DZNE), Greifswald, Germany
- Center for Biomedical Image Computing and Analytics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Robert A. Bittner
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe University, Frankfurt, Germany
| | - Hong Pan
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Sandra Goebbels
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Martin Begemann
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
| | - Ulrike C. Gerwig
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Sönke Langner
- Institute of Diagnostic Radiology and Neuroradiology
| | - Hauke B. Werner
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Sarah Kittel-Schneider
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe University, Frankfurt, Germany
| | - Georg Homuth
- Interfaculty Institute for Genetics and Functional Genomics, and
| | - Christos Davatzikos
- Center for Biomedical Image Computing and Analytics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Henry Völzke
- Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Brian L. West
- Translational Pharmacology, Plexxikon Inc., Berkeley, California, USA
| | - Andreas Reif
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe University, Frankfurt, Germany
| | - Hans Jörgen Grabe
- Department of Psychiatry and Psychotherapy, University Medicine, and German Center for Neurodegenerative Diseases (DZNE), Greifswald, Germany
| | - Susann Boretius
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
- Functional Imaging Laboratory, Leibniz Institute for Primate Research, Göttingen, Germany
| | - Hannelore Ehrenreich
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Klaus-Armin Nave
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
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7
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Mortilla M, Federico A, De Stefano N. Uso della risonanza magnetica spettroscopica del protone nello studio delle malattie della sostanza bianca cerebrale. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/197140090001300113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
La risonanza magnetica spettroscopica (MRS) è una tecnica non invasiva per la misura della concentrazione relativa di alcuni composti cerebrali. L'uso di questa tecnica nello studio delle malattie della materia bianca cerebrale ha apportato miglioramenti nella classificazione diagnostica e nelle misure relative all'andamento delle malattie. Un uso più estensivo delle tecniche di risonanza multimodale, comprendenti tomografia RM, spettroscopia ed altre modalità non convenzionali, dovrebbe quindi essere incoraggiato. Ciò permetterà una miglior comprensione della complessa dinamica dei cambiamenti patologici nelle malattie della sostanza bianca ed una più accurata valutazione della progressione e della risposta alla terapia della malattia stessa.
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Affiliation(s)
- M. Mortilla
- Istituto di Scienze Neurologiche e Centro NMR, Università degli Studi; Siena
| | - A. Federico
- Istituto di Scienze Neurologiche e Centro NMR, Università degli Studi; Siena
| | - N. De Stefano
- Istituto di Scienze Neurologiche e Centro NMR, Università degli Studi; Siena
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8
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Poggi G, Boretius S, Möbius W, Moschny N, Baudewig J, Ruhwedel T, Hassouna I, Wieser GL, Werner HB, Goebbels S, Nave KA, Ehrenreich H. Cortical network dysfunction caused by a subtle defect of myelination. Glia 2016; 64:2025-40. [PMID: 27470661 PMCID: PMC5129527 DOI: 10.1002/glia.23039] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 07/08/2016] [Indexed: 12/11/2022]
Abstract
Subtle white matter abnormalities have emerged as a hallmark of brain alterations in magnetic resonance imaging or upon autopsy of mentally ill subjects. However, it is unknown whether such reduction of white matter and myelin contributes to any disease‐relevant phenotype or simply constitutes an epiphenomenon, possibly even treatment‐related. Here, we have re‐analyzed Mbp heterozygous mice, the unaffected parental strain of shiverer, a classical neurological mutant. Between 2 and 20 months of age, Mbp+/‐ versus Mbp+/+ littermates were deeply phenotyped by combining extensive behavioral/cognitive testing with MRI, 1H‐MR spectroscopy, electron microscopy, and molecular techniques. Surprisingly, Mbp‐dependent myelination was significantly reduced in the prefrontal cortex. We also noticed a mild but progressive hypomyelination of the prefrontal corpus callosum and low‐grade inflammation. While most behavioral functions were preserved, Mbp+/‐ mice exhibited defects of sensorimotor gating, as evidenced by reduced prepulse‐inhibition, and a late‐onset catatonia phenotype. Thus, subtle but primary abnormalities of CNS myelin can be the cause of a persistent cortical network dysfunction including catatonia, features typical of neuropsychiatric conditions. GLIA 2016;64:2025–2040
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Affiliation(s)
- Giulia Poggi
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen
| | - Susann Boretius
- Department of Radiology and Neuroradiology, Christian-Albrechts-University, Kiel.,Department of Functional Imaging, German Primate Center, Leibniz Institute of Primate Research, Göttingen
| | - Wiebke Möbius
- Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen
| | - Nicole Moschny
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen
| | - Jürgen Baudewig
- Department of Radiology and Neuroradiology, Christian-Albrechts-University, Kiel.,Department of Functional Imaging, German Primate Center, Leibniz Institute of Primate Research, Göttingen
| | - Torben Ruhwedel
- Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen
| | - Imam Hassouna
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen
| | - Georg L Wieser
- Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen
| | - Hauke B Werner
- Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen
| | - Sandra Goebbels
- Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen
| | - Klaus-Armin Nave
- Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen. .,DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.
| | - Hannelore Ehrenreich
- Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen. .,DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.
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9
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Gasparova Z, Pronayova N, Stara V, Liptaj T. In Vitro Metabolomic Approach to Hippocampal Neurodegeneration Induced by Trimethyltin. Neurochem Res 2015; 41:715-21. [PMID: 26482153 DOI: 10.1007/s11064-015-1740-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 09/29/2015] [Accepted: 10/13/2015] [Indexed: 11/24/2022]
Abstract
Search for indicators of neurodegenerative disorders is a hot topic where much research remains to be done. Our aim was to determine proton nuclear magnetic resonance ((1)H-NMR) spectra of brain metabolites in the trimethyltin (TMT) model of neurodegeneration. Male Wistar rats were subjected to TMT or saline and were sacrificed on day 3 or 24 after administration. (1)H-NMR spectrum was measured on the 600 MHz Varian VNMRS spectrometer in nano-probe in the volume of 40 μl of hippocampal extracts. TMT administration resulted in reduction of the hippocampal weight on day 24. Of the sixteen identified metabolite spectra, decreased aspartate and increased glutamine contents were observed in the initial asymptomatic stage of neurodegeneration on day 3 in hippocampal extracts of TMT exposed rats compared to sham animals. Increased myo-inositol content was observed on day 24. The presented data provide further knowledge about this experimental model and putative indicators of neuronal damage.
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Affiliation(s)
- Zdenka Gasparova
- Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Bratislava, Slovakia.
| | - Nada Pronayova
- Department of NMR and Mass Spectroscopy, Faculty of Food and Chemical Technology, Slovak University of Technology, Bratislava, Slovakia
| | - Veronika Stara
- Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Bratislava, Slovakia.,Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia
| | - Tibor Liptaj
- Department of NMR and Mass Spectroscopy, Faculty of Food and Chemical Technology, Slovak University of Technology, Bratislava, Slovakia
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10
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Ublinskii MV, Semenova NA, Akhadov TA, Mel´nikov IA, Varfolomeev SD. Relaxation kinetics in the study of neurobiological processes using functional magnetic resonance imaging and spectroscopy. Russ Chem Bull 2015. [DOI: 10.1007/s11172-015-0885-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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11
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Tiwari V, Solanki V, Tiwari M. In-vivoandin-vitrotechniques used to investigate Alzheimer's disease. FRONTIERS IN LIFE SCIENCE 2015. [DOI: 10.1080/21553769.2015.1044129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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12
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Bender B, Klose U, Lindig T, Biskup S, Nägele T, Schöls L, Karle KN. Imaging features in conventional MRI, spectroscopy and diffusion weighted images of hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS). J Neurol 2014; 261:2351-9. [DOI: 10.1007/s00415-014-7509-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/12/2014] [Accepted: 09/13/2014] [Indexed: 11/29/2022]
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13
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Harrington MG, Chiang J, Pogoda JM, Gomez M, Thomas K, Marion SD, Miller KJ, Siddarth P, Yi X, Zhou F, Lee S, Arakaki X, Cowan RP, Tran T, Charleswell C, Ross BD, Fonteh AN. Executive function changes before memory in preclinical Alzheimer's pathology: a prospective, cross-sectional, case control study. PLoS One 2013; 8:e79378. [PMID: 24260210 PMCID: PMC3832547 DOI: 10.1371/journal.pone.0079378] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 09/24/2013] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Early treatment of Alzheimer's disease may reduce its devastating effects. By focusing research on asymptomatic individuals with Alzheimer's disease pathology (the preclinical stage), earlier indicators of disease may be discovered. Decreasing cerebrospinal fluid beta-amyloid42 is the first indicator of preclinical disorder, but it is not known which pathology causes the first clinical effects. Our hypothesis is that neuropsychological changes within the normal range will help to predict preclinical disease and locate early pathology. METHODS AND FINDINGS We recruited adults with probable Alzheimer's disease or asymptomatic cognitively healthy adults, classified after medical and neuropsychological examination. By logistic regression, we derived a cutoff for the cerebrospinal fluid beta amyloid42/tau ratios that correctly classified 85% of those with Alzheimer's disease. We separated the asymptomatic group into those with (n = 34; preclinical Alzheimer's disease) and without (n = 36; controls) abnormal beta amyloid42/tau ratios; these subgroups had similar distributions of age, gender, education, medications, apolipoprotein-ε genotype, vascular risk factors, and magnetic resonance imaging features of small vessel disease. Multivariable analysis of neuropsychological data revealed that only Stroop Interference (response inhibition) independently predicted preclinical pathology (OR = 0.13, 95% CI = 0.04-0.42). Lack of longitudinal and post-mortem data, older age, and small population size are limitations of this study. CONCLUSIONS Our data suggest that clinical effects from early amyloid pathophysiology precede those from hippocampal intraneuronal neurofibrillary pathology. Altered cerebrospinal fluid beta amyloid42 with decreased executive performance before memory impairment matches the deposits of extracellular amyloid that appear in the basal isocortex first, and only later involve the hippocampus. We propose that Stroop Interference may be an additional important screen for early pathology and useful to monitor treatment of preclinical Alzheimer's disease; measures of executive and memory functions in a longitudinal design will be necessary to more fully evaluate this approach.
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Affiliation(s)
- Michael G. Harrington
- Molecular Neurology Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
- * E-mail:
| | - Jiarong Chiang
- Molecular Neurology Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
| | - Janice M. Pogoda
- Keck School of Medicine at the University of Southern California, Los Angeles, California, United States of America
| | - Megan Gomez
- Fuller Graduate School of Psychology, Pasadena, California, United States of America
| | - Kris Thomas
- Fuller Graduate School of Psychology, Pasadena, California, United States of America
| | - Sarah DeBoard Marion
- Fuller Graduate School of Psychology, Pasadena, California, United States of America
| | - Karen J. Miller
- David Geffen School of Medicine, UCLA, Los Angeles, California, United States of America
| | - Prabha Siddarth
- David Geffen School of Medicine, UCLA, Los Angeles, California, United States of America
| | - Xinyao Yi
- Department of Chemistry and Biochemistry, California State University, Los Angeles, California, United States of America
| | - Feimeng Zhou
- Department of Chemistry and Biochemistry, California State University, Los Angeles, California, United States of America
| | - Sherri Lee
- Molecular Neurology Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
| | - Xianghong Arakaki
- Molecular Neurology Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
| | - Robert P. Cowan
- Dept of Neurology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Thao Tran
- Magnetic Resonance Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
| | - Cherise Charleswell
- Magnetic Resonance Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
| | - Brian D. Ross
- Magnetic Resonance Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
| | - Alfred N. Fonteh
- Molecular Neurology Program, Huntington Medical Research Institutes, Pasadena, California, United States of America
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R-flurbiprofen improves tau, but not Aß pathology in a triple transgenic model of Alzheimer's disease. Brain Res 2013; 1541:115-27. [PMID: 24161403 DOI: 10.1016/j.brainres.2013.10.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 10/10/2013] [Accepted: 10/15/2013] [Indexed: 11/24/2022]
Abstract
We have previously reported that chronic ibuprofen treatment improves cognition and decreases intracellular Aß and phosphorylated-tau levels in 3xTg-AD mice. Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) that independently of its anti-inflammatory effects has anti-amyloidogenic activity as a gamma-secretase modulator (GSM) and both activities have the potential to decrease Aß pathology. To further understand the effects of NSAIDs in 3xTg-AD mice, we treated 3xTg-AD mice with R-flurbiprofen, an enantiomer of the NSAID flurbiprofen that maintains the GSM activity but has greatly reduced anti-inflammatory activity, and analyzed its effect on cognition, Aß, tau, and the neurochemical profile of the hippocampus. Treatment with R-flurbiprofen from 5 to 7 months of age resulted in improved cognition on the radial arm water maze (RAWM) test and decreased the level of hyperphosphorylated tau immunostained with AT8 and PHF-1 antibodies. No significant changes in the level of Aß (using 6E10 and NU-1 antibodies) were detected. Using magnetic resonance spectroscopy (MRS) we found that R-flurbiprofen treatment decreased the elevated level of glutamine in 3xTg-AD mice down to the level detected in non-transgenic mice. Glutamine levels correlated with PHF-1 immunostained hyperphosphorylated tau. We also found an inverse correlation between the concentration of glutamate and learning across all the mice in the study. Glutamine and glutamate, neurochemicals that shuttles between neurons and astrocytes to maintain glutamate homeostasis in the synapses, deserve further attention as MR markers of cognitive function.
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Jian H, Yi-Fang W, Qi L, Xiao-Song H, Gui-Yun Z. Cerebral blood flow and metabolic changes in hippocampal regions of a modified rat model with chronic cerebral hypoperfusion. Acta Neurol Belg 2013; 113:313-7. [PMID: 23111782 DOI: 10.1007/s13760-012-0154-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 10/16/2012] [Indexed: 10/27/2022]
Abstract
Chronic cerebral hypoperfusion (CCH) causes neurodegeneration which contributes to the cognitive impairment. This study utilized a modified rat model with CCH to investigate cerebral blood flow (CBF) and hippocampal metabolic changes. CBF was measured by laser Doppler flowmetry. Various metabolic ratios were evaluated from selective volumes of interest (VOI) in left hippocampal regions using in vivo proton magnetic resonance spectroscopy ((1)H-MRS). The ultrastructural changes with special respect to ribosomes in rat hippocampal CA1 neurons were studied by electron microscopy. CBF decreased immediately after CCH and remained reduced significantly at 1 day and 3 months postoperatively. (1)H-MRS revealed that CCH led to a significant decrease of N-acetyl aspartate/creatine (NAA/Cr) ratio in the hippocampal VOI in the model rats compared with the sham-operated control rats. However, no changes of myo-inositol/Cr, choline/Cr and glutamate and glutamine/Cr ratios between the model and control groups were observed. Under electron microscopy, most rosette-shaped polyribosomes were relatively evenly distributed in the hippocampal CA1 neuronal cytoplasms of the control rats. After CCH, most ribosomes were clumped into large abnormal aggregates in the model rats. Our data suggests that both permanent decrease of CBF and reduction of NAA/Cr ratio in the hippocampal regions may be related to the cognitive deficits in rats with CCH.
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Karczewska-Kupczewska M, Tarasów E, Nikolajuk A, Stefanowicz M, Matulewicz N, Otziomek E, Górska M, Straczkowski M, Kowalska I. The effect of insulin infusion on the metabolites in cerebral tissues assessed with proton magnetic resonance spectroscopy in young healthy subjects with high and low insulin sensitivity. Diabetes Care 2013; 36:2787-93. [PMID: 23596182 PMCID: PMC3747869 DOI: 10.2337/dc12-1437] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Insulin may play important roles in brain metabolism. Proton magnetic resonance spectroscopy ((1)H-MRS) of the central nervous system gives information on neuronal viability, cellular energy, and membrane status. To elucidate the specific role of insulin action in the brain, we estimated neurometabolites with (1)H-MRS and assessed their regulation by insulin infusion and their relationship with insulin sensitivity. RESEARCH DESIGN AND METHODS We studied 16 healthy young men. (1)H-MRS was performed at baseline and after 240 min of euglycemic-hyperinsulinemic clamp. Voxels were positioned in the left frontal lobe, left temporal lobe, and left thalamus. The ratios of N-acetylaspartate (NAA), choline-containing compounds (Cho), myo-inositol, and glutamate/glutamine/γ-aminobutyric acid complex (Glx) to creatine (Cr) and nonsuppressed water signal were determined. The participants were divided into subgroups of high (high IS) and low (low IS) insulin sensitivity. RESULTS Baseline neurometabolic substrates were not different between the groups. Insulin infusion resulted in an increase in frontal NAA/Cr and NAA/H2O and frontal and temporal Glx/Cr and Glx/H2O and a decrease in frontal Cho/Cr and temporal Cho/H2O and myo-inositol/H2O (all P < 0.05, except temporal Glx/H2O, P = 0.054, NS) in the high-IS, but not in the low-IS, group. Insulin sensitivity correlated positively with frontal NAA/Cr and NAA/H2O and temporal Glx/H2O and negatively with temporal myo-inositol/Cr and myo-inositol/H2O assessed during the second (1)H-MRS (all P < 0.05). CONCLUSIONS Insulin might influence cerebral metabolites, and this action is impaired in subjects with low whole-body insulin sensitivity. Thus, our results provide a potential link between insulin resistance and altered metabolism of the central nervous system.
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Affiliation(s)
- Monika Karczewska-Kupczewska
- Department of Endocrinology, Diabetology, and Internal Medicine, Medical University of Białystok, Białystok, Poland.
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Lee H, Caparelli E, Li H, Mandal A, Smith SD, Zhang S, Bilfinger TV, Benveniste H. Computerized MRS voxel registration and partial volume effects in single voxel 1H-MRS. Magn Reson Imaging 2013; 31:1197-205. [PMID: 23659770 DOI: 10.1016/j.mri.2013.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 02/23/2013] [Accepted: 04/02/2013] [Indexed: 01/01/2023]
Abstract
Partial volume effects in proton magnetic resonance spectroscopy in the brain have been studied previously in terms of proper water concentration calculations, but there is a lack of disclosure in terms of voxel placement techniques that would affect the calculations. The purpose of this study is to facilitate a fully automated MRS voxel registration method which is time efficient, accurate, and can be extended to all imaging modalities. A total of thirteen healthy adults underwent single voxel 1H-MRS scans in 3.0T MRI scanners. Transposition of a MRS voxel onto an anatomical scan is derived along with a full calculation of water concentration with a correction term to account for the partial volume effects. Five metabolites (tNAA, Glx, tCr, mI, and tCho) known to yield high reliability are studied. Pearson's correlation analyses between tissue volume fractions and metabolite concentrations were statistically significant in parietal (tCr, Glx, and tNAA) lobe and occipital lobe (tNAA). MRS voxel overlaps quantified by dice metric over repeated visits yielded 60%~70% and coefficients of variance in metabolites concentration were 4%~10%. These findings reiterate an importance of considering the partial volume effects when tissue water is used as an internal concentration reference so as to avoid misinterpreting a morphometric difference as a metabolic difference.
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Affiliation(s)
- Hedok Lee
- Department of Anesthesiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA.
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Silveira de Souza A, de Oliveira-Souza R, Moll J, Tovar-Moll F, Andreiuolo PA, Bottino CMC. Contribution of 1H spectroscopy to a brief cognitive-functional test battery for the diagnosis of mild Alzheimer's disease. Dement Geriatr Cogn Disord 2012; 32:351-61. [PMID: 22311276 DOI: 10.1159/000334656] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/21/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS The diagnosis of mild or questionable Alzheimer's disease (AD) depends on clinical criteria that often leave a margin for doubt. We aim to verify the diagnostic accuracy of amnestic mild cognitive impairment (aMCI) and AD with proton spectroscopy (1H-MRS) combined with brief cognitive-functional scales. METHODS The relationship between 1H-MRS of the posterior cingulate cortex and the cognitive performance in Mini Mental State Examination, Blessed-Roth Dementia Rating and Functional Assessment Staging of Alzheimer Disease scales were investigated in 25 AD, 10 aMCI and 33 normal control (NC) individuals. RESULTS The N-acetylaspartate (NAA)/creatine and myoinositol/NAA ratios distinguished AD patients from NC (p<0.005), and added value in diagnostic accuracy and specificity by discriminant function analysis when combined to clinical diagnosis and simple neuropsychiatric scales; an increase of 3.7% (for aMCI patients) and of 5% (for AD individuals) was observed in diagnostic accuracy, and one of 5.5% (aMCI) and of 11.1% (AD) in specificity. CONCLUSION 1H-MRS combined with brief cognitive-functional scales provided maximum diagnostic accuracy of AD patients, and can be useful when subtle cognitive and memory dysfunction is present.
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Guilarte TR, Opler M, Pletnikov M. Is lead exposure in early life an environmental risk factor for Schizophrenia? Neurobiological connections and testable hypotheses. Neurotoxicology 2012; 33:560-74. [PMID: 22178136 PMCID: PMC3647679 DOI: 10.1016/j.neuro.2011.11.008] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 11/30/2011] [Accepted: 11/30/2011] [Indexed: 02/06/2023]
Abstract
Schizophrenia is a devastating neuropsychiatric disorder of unknown etiology. There is general agreement in the scientific community that schizophrenia is a disorder of neurodevelopmental origin in which both genes and environmental factors come together to produce a schizophrenia phenotype later in life. The challenging questions have been which genes and what environmental factors? Although there is evidence that different chromosome loci and several genes impart susceptibility for schizophrenia; and epidemiological studies point to broad aspects of the environment, only recently there has been an interest in studying gene × environment interactions. Recent evidence of a potential association between prenatal lead (Pb(2+)) exposure and schizophrenia precipitated the search for plausible neurobiological connections. The most promising connection is that in schizophrenia and in developmental Pb(2+) exposure there is strong evidence for hypoactivity of the N-methyl-d-aspartate (NMDA) subtype of excitatory amino acid receptors as an underlying neurobiological mechanism in both conditions. A hypofunction of the NMDA receptor (NMDAR) complex during critical periods of development may alter neurobiological processes that are essential for brain growth and wiring, synaptic plasticity and cognitive and behavioral outcomes associated with schizophrenia. We also describe on-going proof of concept gene-environment interaction studies of early life Pb(2+) exposure in mice expressing the human mutant form of the disrupted in schizophrenia 1 (DISC-1) gene, a gene that is strongly associated with schizophrenia and allied mental disorders.
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Affiliation(s)
- Tomás R Guilarte
- Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, NY 10032, United States.
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20
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Semenova NA, Akhadov TA, Petryaykin AV, Sidorin SS, Lukovenkov AV, Varfolomeev SD. Metabolic dysfunction and relationship in human frontoparietal cortex in severe traumatic brain injury: Single-voxel 1H magnetic resonance spectroscopy study. BIOCHEMISTRY (MOSCOW) 2012; 77:388-94. [DOI: 10.1134/s0006297912040104] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Gender-dependent behavioural impairment and brain metabolites in young adult rats after short term exposure to lead acetate. Toxicol Lett 2012; 210:15-23. [PMID: 22285975 DOI: 10.1016/j.toxlet.2012.01.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 01/12/2012] [Accepted: 01/13/2012] [Indexed: 01/13/2023]
Abstract
We investigated the behavioural effects of short-term lead (Pb) exposure in adult rats producing blood Pb concentration (<10 μg/dL) below those associated with neurological impairment in occupationally exposed individuals. In order to assess gender differences, we performed parallel behavioural experiments in male and female rats. Exposure to Pb acetate (50 mg/L in drinking water) for 30-45 days induced behavioural alterations consisting in hyperactivity in a novel environment and impairment of spatial memory. These effects were observed only in male rats. Object recognition, motor coordination were unaffected by Pb exposure. Magnetic resonance spectroscopy allows in vivo assessment of main brain metabolites (glutamate/glutamine, creatine, myoinositol, N-acetylaspartate and choline) whose changes have been demonstrated in several central nervous system pathologies. Exposure to Pb did not affect metabolite profile in the striatum and increase myoinositol signal in the hippocampus of male rats. The increase in myoinositol in hippocampus suggests early Pb-induced alteration in glial metabolism in this brain region and may represent a potential marker of early brain dysfunction during Pb exposure.
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Sailasuta N, Harris K, Tran T, Ross B. Minimally invasive biomarker confirms glial activation present in Alzheimer's disease: a preliminary study. Neuropsychiatr Dis Treat 2011; 7:495-9. [PMID: 21931491 PMCID: PMC3173032 DOI: 10.2147/ndt.s23721] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We applied (13)C magnetic resonance spectroscopy (MRS), a nonradioactive, noninvasive brain imaging technique, to quantify the oxidation of [1-(13)C] acetate in a conventional clinical magnetic resonance imaging (MRI) scanner in five consecutive elderly subjects at various clinical stages of Alzheimer's disease (AD) progression. [1-(13)C] acetate entered the brain and was metabolized to [5-(13)C] glutamate and glutamine, as well as [1-(13)C] glutamate and glutamine, and the final glial oxidation product, (13)C bicarbonate, at a linear rate. Calculation of the initial slope was similar in a single subject, examined twice, 1 month apart (test-re-test 8%). Mean rate of cerebral bicarbonate production in this elderly group was 0.040 ± 0.01 (n = 5). Assuming that the rate of conversion of acetate to bicarbonate is a reflection of glial metabolic rate and that glial metabolic rate is a surrogate marker for 'neuroinflammation', our preliminary results suggest that [1-(13)C] MRS may provide biomarkers for diseases, believed to involve microglia and other cells of the astrocyte series. Among these is AD, for which novel drugs which ameliorate the damaging effects of neuroinflammation before symptoms of dementia appear, are in advanced development. The value of (13)C MRS as an early, noninvasive biomarker may lie in the conduct of cost-effective clinical trials.
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Affiliation(s)
- Napapon Sailasuta
- Clinical MR Unit, Huntington Medical Research Institutes, Pasadena, CA, USA
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Haley AP, Gonzales MM, Tarumi T, Miles SC, Goudarzi K, Tanaka H. Elevated cerebral glutamate and myo-inositol levels in cognitively normal middle-aged adults with metabolic syndrome. Metab Brain Dis 2010; 25:397-405. [PMID: 21063759 DOI: 10.1007/s11011-010-9221-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 09/15/2010] [Indexed: 11/25/2022]
Abstract
Metabolic syndrome (MetS) is a cluster of risk factors associated with significant cardiovascular morbidity and mortality and diminished cognitive function. Given that the cerebral mechanisms mediating the relationship between peripheral metabolic dysfunction and cognitive impairment are unknown, we set out to examine the relationship between diagnosis of metabolic syndrome and cerebral metabolism. Thirteen participants with MetS (aged 48 ± 6 years) and 25 healthy adults (aged 51 ± 6 years) underwent neuropsychological assessment, health screen and proton magnetic resonance spectroscopy ((1)H MRS) examining N-acetyl-aspartate (NAA), myo-inositol (mI), creatine (Cr), choline (Cho), and glutamate (Glu) concentrations in occipitoparietal grey matter. Cerebral metabolite ratios (NAA/Cr, Cho/Cr, mI/Cr, and Glu/Cr) of participants with MetS, defined by the International Diabetes Federation criteria, were compared with controls matched for age, education, cognition, and emotional function. There were no significant differences in global cognitive function, memory, language, and psychomotor performance between the groups. Diagnosis of MetS was associated with significantly higher mI/Cr (F(1,36) = 5.02, p = 0.031) and Glu/Cr ratio (F(1,36) = 4.81, p = 0.035). Even in cognitively normal adults, MetS is related to cerebral metabolic disturbances, a possible indication of early brain vulnerability. Longitudinal studies that begin in mid-life can help validate the use of (1)H MRS markers as indicators of long-term cognitive outcomes.
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Affiliation(s)
- Andreana P Haley
- Department of Psychology, The University of Texas at Austin, 1 University Station, A8000, Austin, TX 78712, USA.
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Mountford CE, Stanwell P, Lin A, Ramadan S, Ross B. Neurospectroscopy: the past, present and future. Chem Rev 2010; 110:3060-86. [PMID: 20387805 DOI: 10.1021/cr900250y] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Carolyn E Mountford
- Centre for Clinical Spectroscopy, Department of Radiology, Brigham & Women's Hospital, Harvard Medical School, 4 Blackfan Street, HIM-817, Boston, Massachusetts 02115, USA.
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Carmody S, Brennan L. Effects of pentylenetetrazole-induced seizures on metabolomic profiles of rat brain. Neurochem Int 2009; 56:340-4. [PMID: 19913064 DOI: 10.1016/j.neuint.2009.11.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2009] [Revised: 11/02/2009] [Accepted: 11/06/2009] [Indexed: 11/18/2022]
Abstract
Epilepsy is one of the most common neurological disorders and approximately one-third of patients with epilepsy are resistant to treatment. In order to develop our understanding of the metabolic changes occurring during seizure a metabolomic approach was employed. Using a pentylenetetrazole (PTZ) kindling model of epilepsy metabolomic analysis of brain extracts from the cerebellum, brain stem, prefrontal cortex and hippocampus was performed. Principal component analysis (PCA) of the (1)H NMR derived data revealed a distinct metabolic profile for each brain region. In order to assess the changes occurring following seizure partial least square discriminant analysis (PLS-DA) models for each brain region for PTZ-kindled and control animals were constructed. For all the brain regions good predictive models were built and the discriminating metabolites were identified. Results following one injection of PTZ indicated that the changes observed in the cerebellum and hippocampus were mainly due to seizure. In the hippocampus of PTZ-kindled animals the metabolites changing included lactate, succinate, GABA, NAA, choline and taurine. Analysis of the cerebellum of PTZ-kindled animals revealed changes in lactate, myo-inositol, choline, GABA, creatine, succinate, phosphocholine and GPC. Overall, the results indicate that seizure may be associated with an increase in energy demand, altered neurotransmitter balance and an increase in neuronal loss and gliosis.
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Affiliation(s)
- Stacey Carmody
- UCD School of Agriculture, Food Science and Veterinary Medicine, UCD Conway Institute, University College Dublin (UCD), Dublin 4, Ireland
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26
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Chang Y, Woo ST, Lee JJ, Song HJ, Lee HJ, Yoo DS, Kim SH, Lee H, Kwon YJ, Ahn HJ, Ahn JH, Park SJ, Weon YC, Chung IS, Jeong KS, Kim Y. Neurochemical changes in welders revealed by proton magnetic resonance spectroscopy. Neurotoxicology 2009; 30:950-7. [PMID: 19631686 DOI: 10.1016/j.neuro.2009.07.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 07/13/2009] [Accepted: 07/14/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Occupational and environmental exposure to manganese (Mn) is associated with various neurobehavioral and movement dysfunctions. However, few studies have systemically examined the neurochemical effects of Mn exposure. OBJECTIVES We examined typical changes in cerebral metabolite ratios in welders chronically exposed to Mn, compared with control individuals, using proton magnetic resonance spectroscopy (MRS), investigated whether an abnormality in brain metabolism is associated with neurobehavioral changes, and assessed possible implications of chronic Mn exposure. METHODS Thirty-five welders chronically exposed to Mn and 20 age-matched healthy subjects underwent single-voxel MRS at short echo time to assess the N-acetylaspartate (NAA), myoinositol (mI), total choline (tCho), and glutamine plus glutamate (Glx) levels, each of which was expressed as a ratio to total creatine (tCr). Neurobehavioral tests were also performed to define cognitive status. RESULTS NAA/tCr, Glx/tCr, and tCho/tCr ratios in the frontal gray matter (anterior cingulate cortex; ACC) and parietal white matter did not differ significantly between welders and control subjects. These metabolite ratios did not correlate significantly with blood Mn concentration or neurobehavioral parameters. However, mI levels in the ACC, but not in the parietal white matter, were significantly reduced in welders compared with control individuals (P<0.01). Furthermore, in the frontal lobe of the brain, the mI/tCr ratio was significantly correlated with verbal memory scores as well as blood Mn concentration (P<0.05). CONCLUSIONS The cognitive decline observed in welders exposed to Mn was associated with a decreased mI/tCr ratio in the ACC. The depletion of mI in welders may reflect possible glial cell swelling and/or detoxification processes associated with long-term exposure to Mn.
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Affiliation(s)
- Yongmin Chang
- Department of Molecular Medicine, Kyungpook National University College of Medicine, Kyungpook National University Hospital, Daegu, South Korea
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27
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Shi C, Wang X, Wu S, Zhu Y, Chung LWK, Mao H. HRMAS 1H-NMR measured changes of the metabolite profile as mesenchymal stem cells differentiate to targeted fat cells in vitro: implications for non-invasive monitoring of stem cell differentiation in vivo. J Tissue Eng Regen Med 2009; 2:482-90. [PMID: 18932127 DOI: 10.1002/term.120] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Mesenchymal stem cells (MSCs) have shown a great potential for clinical applications in regenerative medicine. However, it remains challenging to follow the transplanted cell grafts in vivo. Nuclear magnetic resonance spectroscopy (NMR or MRS) is capable of determining and quantifying the cellular metabolites in tissue and organs non-invasively, therefore it is an attractive method for monitoring and evaluating the differentiation and functions of transplanted stem cells in vivo. In this study, metabolic changes of MSCs undergoing adipogenic differentiation to targeted fat cells were investigated in vitro, using solid-state high-resolution magic angle spinning (1)H nuclear magnetic resonance spectroscopy. Quantification of metabolite concentrations before and after differentiation of MSCs showed decreased levels of intracellular metabolites, including choline, creatine, glutamate and myo-inositol, and a substantially increased level of fatty acids, when mesenchymal stem cells were differentiated preferentially to fat cells. Intracellular creatine, myo-inositol and choline reduced from 10.4 +/- 0.72, 16.2 +/- 1.2 and 8.22 +/- 0.51 mM to 3.27 +/- 0.34, 6.1 +/- 0.46 and 3.11 +/- 0.32 mM, respectively, while fatty acids increased from 32.6 +/- 1.5 to 91.2 +/- 3.2 mM after undergoing 3 weeks of differentiation. The increase of the fatty acid concentration measured by NMR is confirmed by the observation of 80% fat cells in differentiated cells by cell counting assay, suggesting resonances from fatty acids may be used as metabolite markers for monitoring MSC differentiation to fat cells in vivo, using the magnetic resonance spectroscopic technique readily available on MRI scanners.
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Affiliation(s)
- Chunmeng Shi
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Third Military Medical University, Chongqing 400038, People's Republic of China
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Westman E, Spenger C, Oberg J, Reyer H, Pahnke J, Wahlund LO. In vivo 1H-magnetic resonance spectroscopy can detect metabolic changes in APP/PS1 mice after donepezil treatment. BMC Neurosci 2009; 10:33. [PMID: 19351388 PMCID: PMC2674598 DOI: 10.1186/1471-2202-10-33] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Accepted: 04/07/2009] [Indexed: 12/27/2022] Open
Abstract
Background Donepezil improves cognitive functions in AD patients. Effects on the brain metabolites N-acetyl-L-aspartate, choline and myo-inositol levels have been reported in clinical studies using this drug. The APP/PS1 mouse coexpresses the mutated forms of human β-amyloid precursor protein (APP) and mutated human presenilin 1 (PS1). Consequently, the APP/PS1 mouse model reflects important features of the neurochemical profile in humans. In vivo magnetic resonance spectroscopy (1H-MRS) was performed in fronto-parietal cortex and hippocampus (ctx/hipp) and in striatum (str). Metabolites were quantified using the LCModel and the final analysis was done using multivariate data analysis. The aim of this study was to investigate if multivariate data analysis could detect changes in the pattern of the metabolic profile after donepezil treatment. Results Significant differences were observed in the metabolic pattern of APP/PS1 mice in both str and ctx/hipp before and after donepezil treatment using multivariate data analysis, evidencing a significant treatment effect. A treatment effect was also seen in wild type (wt) mice in str. A significant decrease in the metabolic ratio taurine/creatine (Tau/tCr) was related to donepezil treatment (p < 0.05) in APP/PS1 mice in both brain regions. Furthermore, a significant influence on the choline/creatine (tCho/tCr) level was observed in treated APP/PS1 mice compared to untreated in str (p = 0.011). Finally, there was an increase in glutamate/creatine (Glu/tCr) in str in wt mice treated with donepezil. Conclusion Multivariate data analysis can detect changes in the metabolic profile in APP/PS1 mice after donepezil treatment. Effects on several metabolites that are measurable in vivo using MR spectroscopy were observed. Changes in Tau/tCr and tCho/tCr could possibly be related to changed cholinergic activity caused by donepezil treatment.
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Affiliation(s)
- Eric Westman
- Department of Neurobiology, Health Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
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de Win MML, Jager G, Booij J, Reneman L, Schilt T, Lavini C, Olabarriaga SD, den Heeten GJ, van den Brink W. Sustained effects of ecstasy on the human brain: a prospective neuroimaging study in novel users. Brain 2008; 131:2936-45. [PMID: 18842607 DOI: 10.1093/brain/awn255] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Previous studies have suggested toxic effects of recreational ecstasy use on the serotonin system of the brain. However, it cannot be excluded that observed differences between users and non-users are the cause rather than the consequence of ecstasy use. As part of the Netherlands XTC Toxicity (NeXT) study, we prospectively assessed sustained effects of ecstasy use on the brain in novel ecstasy users using repeated measurements with a combination of different neuroimaging parameters of neurotoxicity. At baseline, 188 ecstasy-naive volunteers with high probability of first ecstasy use were examined. After a mean period of 17 months follow-up, neuroimaging was repeated in 59 incident ecstasy users and 56 matched persistent ecstasy-naives and their outcomes were compared. Neuroimaging included [(123)I]beta-carbomethoxy-3beta-(4-iodophenyl)tropane (CIT) SPECT to measure serotonin transporter densities as indicators of serotonergic function; (1)H-MR spectroscopy ((1)H-MRS) to measure brain metabolites as indicators of neuronal damage; diffusion tensor imaging (DTI) to measure the apparent diffusion coefficient and fractional anisotropy (FA) of the diffusional motion of water molecules in the brain as indicators of axonal integrity; and perfusion weighted imaging (PWI) to measure regional relative cerebral blood volume (rrCBV) which indicates brain perfusion. With this approach, both structural ((1)H-MRS and DTI) and functional ([(123)I]beta-CIT SPECT and PWI) aspects of neurotoxicity were combined. Compared to persistent ecstasy-naives, novel low-dose ecstasy users (mean 6.0, median 2.0 tablets) showed decreased rrCBV in the globus pallidus and putamen; decreased FA in thalamus and frontoparietal white matter; increased FA in globus pallidus; and increased apparent diffusion coefficient in the thalamus. No changes in serotonin transporter densities and brain metabolites were observed. These findings suggest sustained effects of ecstasy on brain microvasculature, white matter maturation and possibly axonal damage due to low dosages of ecstasy. Although we do not know yet whether these effects are reversible or not, we cannot exclude that ecstasy even in low doses is neurotoxic to the brain.
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Affiliation(s)
- Maartje M L de Win
- Department of Radiology, University of Amsterdam, Academic Medical Center, Amsterdam, The Netherlands.
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Craig MC, Daly EM, O'Gorman R, Rymer J, Lythgoe D, Ng G, Simmons A, Maki PM, Murphy DGM. Effects of acute ovarian hormone suppression on the human brain: an in vivo 1H MRS study. Psychoneuroendocrinology 2007; 32:1128-32. [PMID: 17658694 DOI: 10.1016/j.psyneuen.2007.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 06/01/2007] [Accepted: 06/02/2007] [Indexed: 11/16/2022]
Abstract
A previous proton magnetic resonance spectroscopy ((1)H MRS) study carried out by our group indicated that post-menopausal women who started taking oestrogen therapy (ET) at or around the menopause had a significantly lower choline (Cho) concentration in the hippocampus and parietal lobe than those who were ET naïve, suggesting that long-term ET positively modulates neuronal/glial membrane turnover in older females. The objective of the current study was to determine whether neuronal membrane turnover is modulated by sex hormones in younger women following a pharmacologic challenge that induced acute ovarian hormone suppression. We carried out an in vivo(1)H MRS study in a group of 10 premenopausal women pre- and post-8 weeks of acute ovarian suppression with a Gonadotrophin Releasing Hormone analogue (GnRHa) (two Zoladex 3.6 mg implants). We report that young women, post-ovarian suppression, had a significant increase in Cho concentration (and Cho/Cr ratio) in the dorsolateral prefrontal cortex (DLPFC). They also showed a trend to a significant increase in Cho concentration in the hippocampus. This supports our previous findings and adds to the evidence that neuronal/glial membrane metabolism is affected by sex hormones in women.
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Affiliation(s)
- Michael C Craig
- Department of Psychological Medicine, Institute of Psychiatry, Section of Brain Maturation, London, UK.
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Mao H, Toufexis D, Wang X, Lacreuse A, Wu S. Changes of metabolite profile in kainic acid induced hippocampal injury in rats measured by HRMAS NMR. Exp Brain Res 2007; 183:477-85. [PMID: 17668196 DOI: 10.1007/s00221-007-1061-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Accepted: 07/04/2007] [Indexed: 11/28/2022]
Abstract
The solid-state high resolution magic angle spinning nuclear magnetic resonance (HRMAS NMR) technique was applied in this work to characterize and quantify the neurochemical changes in the rat hippocampus (CA1 or CA3) after local administration of kainic acid (KA). Intact tissue samples obtained from the KA treated and control brain samples were analyzed using HRMAS NMR. Metabolite profiles from NMR spectra of KA treated and control samples revealed the statistical significant decrease of N-acetylaspartate (NAA) and an increase of choline derivatives in the CA1 and CA3 directly receiving KA injection. Less extensive KA-induced metabolic changes were found in the hippocampi sample from the area contralateral to the site receiving KA administration. These results provided quantitative metabolic information on KA-induced neuronal loss and cell breakdown. In addition, the present study also revealed increased level of gamma-aminobutyric acid (GABA) and glutamate after KA treatment, suggesting that the cellular release of inhibitory and excitatory amino acids can be quantified using this method. KA induced microglia activation was evidenced by increased level of myo-insitol (myo-I). This study demonstrates that ex vivo HRMAS NMR is a useful tool for analyzing and quantifying changes of neurochemistry and cerebral metabolism in the intact brain.
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Affiliation(s)
- Hui Mao
- Department of Radiology and Frederick Philips MR Research Center, Emory University School of Medicine, 1364 Clifton Road, Atlanta, Georgia 30322, USA,
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Shinno H, Inagaki T, Miyaoka T, Okazaki S, Kawamukai T, Utani E, Inami Y, Horiguchi J. A decrease in N-acetylaspartate and an increase in myoinositol in the anterior cingulate gyrus are associated with behavioral and psychological symptoms in Alzheimer's disease. J Neurol Sci 2007; 260:132-8. [PMID: 17540407 DOI: 10.1016/j.jns.2007.04.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 04/16/2007] [Accepted: 04/17/2007] [Indexed: 01/21/2023]
Abstract
BACKGROUND AND PURPOSE The cognitive decline in Alzheimer's disease (AD) patients has been reported to involve alterations in the medial temporal lobe and the posterior cingulate gyrus. On the other hand, the neurochemical pathologies of the behavioral and psychological symptoms of dementia (BPSD) have not been sufficiently discussed. The aim of this study was to clarify the pathologies of BPSD in AD patients. METHODS Thirty patients with probable AD were included and underwent the following assessments: Mini Mental State Examination (MMSE), Clock Drawing Test (CDT), Story Recall Test (SRT), Behavioral pathology in Alzheimer's disease (BEHAVE-AD) and proton MRS ((1)H-MRS). None of them had been medicated for BPSD. RESULTS The MRS study revealed that MMSE, CDT, and SRT scores were positively related to N-acetyl-aspartate (NAA)/creatine(Cr) and negatively related to myoinositol (mI)/Cr in the posterior cingulate gyrus, but not in the anterior cingulate gyrus. On the other hand, the scores obtained in two categories of BEHAVE-AD (delusional thought/ activity disturbances) were negatively related with NAA/Cr and positively related with mI/Cr in the anterior cingulate gyrus, but not in the posterior cingulate gyrus. CONCLUSION We conclude that BPSD and the decline in cognitive function in AD might have separate pathologies.
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Affiliation(s)
- Hideto Shinno
- Department of Psychiatry, Shimane University Faculty of Medicine, Izumo, Japan.
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de Win MML, Reneman L, Jager G, Vlieger EJP, Olabarriaga SD, Lavini C, Bisschops I, Majoie CBLM, Booij J, den Heeten GJ, van den Brink W. A prospective cohort study on sustained effects of low-dose ecstasy use on the brain in new ecstasy users. Neuropsychopharmacology 2007; 32:458-70. [PMID: 17077812 DOI: 10.1038/sj.npp.1301225] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It is debated whether ecstasy use has neurotoxic effects on the human brain and what the effects are of a low dose of ecstasy use. We prospectively studied sustained effects (>2 weeks abstinence) of a low dose of ecstasy on the brain in ecstasy-naive volunteers using a combination of advanced MR techniques and self-report questionnaires on psychopathology as part of the NeXT (Netherlands XTC Toxicity) study. Outcomes of proton magnetic resonance spectroscopy (1H-MRS), diffusion tensor imaging (DTI), perfusion-weighted imaging (PWI), and questionnaires on depression, impulsivity, and sensation seeking were compared in 30 subjects (12M, 21.8+/-3.1 years) in two sessions before and after first ecstasy use (1.8+/-1.3 tablets). Interval between baseline and follow-up was on average 8.1+/-6.5 months and time between last ecstasy use and follow-up was 7.7+/-4.4 weeks. Using 1H-MRS, no significant changes were observed in metabolite concentrations of N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), and creatine (Cr), nor in ratios of NAA, Cho, and mI relative to Cr. However, ecstasy use was followed by a sustained 0.9% increase in fractional anisotropy (FA) in frontoparietal white matter, a 3.4% decrease in apparent diffusion (ADC) in the thalamus and a sustained decrease in relative regional cerebral blood volume (rrCBV) in the thalamus (-6.2%), dorsolateral frontal cortex (-4.0%), and superior parietal cortex (-3.0%) (all significant at p<0.05, paired t-tests). After correction for multiple comparisons, only the rrCBV decrease in the dorsolateral frontal cortex remained significant. We also observed increased impulsivity (+3.7% on the Barratt Impulsiveness Scale) and decreased depression (-28.0% on the Beck Depression Inventory) in novel ecstasy users, although effect sizes were limited and clinical relevance questionable. As no indications were found for structural neuronal damage with the currently used techniques, our data do not support the concern that incidental ecstasy use leads to extensive axonal damage. However, sustained decreases in rrCBV and ADC values may indicate that even low ecstasy doses can induce prolonged vasoconstriction in some brain areas, although it is not known whether this effect is permanent. Additional studies are needed to replicate these findings.
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Affiliation(s)
- Maartje M L de Win
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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Modrego PJ, Pina MA, Fayed N, Díaz M. Changes in metabolite ratios after treatment with rivastigmine in Alzheimer's disease: a nonrandomised controlled trial with magnetic resonance spectroscopy. CNS Drugs 2007; 20:867-77. [PMID: 16999455 DOI: 10.2165/00023210-200620100-00006] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
BACKGROUND Alzheimer's disease is associated with abnormalities in the levels of some brain metabolites, including decreases in N-acetyl-aspartate (NAA) and increases in myo-inositol and choline levels. Cholinesterase inhibitors have proven modest effects on cognition in patients with mild or moderate Alzheimer's disease; however, there is little information on the effects of these drugs on metabolic parameters in the brain. Magnetic resonance spectroscopy (MRS) provides a method of determining changes in such parameters. OBJECTIVE To assess the effect of rivastigmine on metabolite levels in different areas of the brain, and whether changes in metabolite levels correlate with clinical outcome, in patients with Alzheimer's disease compared with untreated patients with Alzheimer's disease. METHODS Twenty-four consecutive patients with mild or moderate Alzheimer's disease were enrolled in the study and were treated with rivastigmine at a target dosage of 12 mg/day for 4 months. A comparison group of ten consecutive untreated patients with Alzheimer's disease with similar cognitive impairment to the treatment group were also enrolled. Each patient underwent assessment using the Mini-Mental State Examination (Spanish version), the Blessed Dementia Rating Scale, the Clinical Dementia Rating scale, the Interview for Deterioration in Daily living activities in Dementia, the Alzheimer's Disease Assessment Scale cognitive and noncognitive subscales, and single-voxel MRS of the frontal, parietal and occipital cortices of the brain to assess levels of brain metabolites (NAA, creatine, choline and myo-inositol) and their ratios to creatine. All assessments were performed at baseline and after 4 months of treatment with rivastigmine, and at baseline and 1 month later in the comparison group. RESULTS Globally, although there was some mean improvement, no significant changes in the cognitive and noncognitive scale scores between baseline and post-treatment assessments were seen in patients who received rivastigmine. A significant increase in the NAA/creatine ratio in the frontal cortex (1.23 at baseline vs 1.3 after treatment; p = 0.026) and in the myo-inositol/creatine ratio in the occipital cortex (0.61 vs 0.65; p = 0.009) was seen in rivastigmine-treated patients. No other significant changes in the metabolite levels or their ratios to creatine were seen in these patients. After correction for multiple comparisons, the significant effects disappeared. Only in the frontal cortex did the changes in metabolite ratios correlate with changes on the clinical scales. In the comparison group, no significant differences between the metabolite levels or ratios to creatine seen with the two scans were detected. CONCLUSION Treatment with rivastigmine showed modest neuronal functional recovery in the frontal cortex only (being able to reverse disease-related decreases in NAA/creatine ratio in this area but unable to affect the disease-related increase in myo-inositol/creatine ratio in any cortex). Since the modest clinical changes correlated with the small changes in the metabolite rates, MRS could be useful in monitoring response to current or future treatments for Alzheimer's disease.
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Metastasio A, Rinaldi P, Tarducci R, Mariani E, Feliziani FT, Cherubini A, Pelliccioli GP, Gobbi G, Senin U, Mecocci P. Conversion of MCI to dementia: Role of proton magnetic resonance spectroscopy. Neurobiol Aging 2006; 27:926-32. [PMID: 15936850 DOI: 10.1016/j.neurobiolaging.2005.05.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2005] [Revised: 04/04/2005] [Accepted: 05/01/2005] [Indexed: 11/15/2022]
Abstract
Mild cognitive impairment (MCI) represents a heterogeneous group of cognitive disturbances at high risk of dementia. The amnestic subtype (aMCI) might be a prodromal state of Alzheimer's disease (AD). The aim of this study is the identification, by proton magnetic resonance spectroscopy (1H MRS), of modifications in brain metabolites able to detect subjects with aMCI at risk of conversion towards AD. Twenty-five subjects with aMCI and 29 normal elderly were enrolled; they underwent a comprehensive clinical and instrumental assessment, a cerebral 1H MRS scan to measure N-acetyl aspartate (NAA), choline (Cho), myo-inositol (mI) and creatine (Cr) in the paratrigonal white matter, bilaterally. After 1 year, 5 MCI subjects became demented (progressive MCI, pMCI). Their baseline levels of metabolites were compared with those evaluated in stable MCI (sMCI) and in controls. We observed a significant difference of the NAA/Cr ratio between pMCI (1.48+/-0.08) and sMCI (1.65+/-0.12) and between pMCI and controls (1.63+/-0.16) in the left hemisphere, suggesting that this metabolic alteration can be detected before the clinical appearance of dementia.
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Affiliation(s)
- Antonio Metastasio
- Institute of Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, University of Perugia, Via Brunamonti 51, 06122 Perugia, Italy
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Ross AJ, Sachdev PS, Wen W, Brodaty H. Longitudinal changes during aging using proton magnetic resonance spectroscopy. J Gerontol A Biol Sci Med Sci 2006; 61:291-8. [PMID: 16567380 DOI: 10.1093/gerona/61.3.291] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE We aimed to examine the longitudinal change in proton magnetic resonance spectroscopy ((1)H-MRS) visible metabolites (N-acetyl aspartate [NAA], creatine [Cr], choline [Cho], and myo-Inositol [mI]) in brains of elderly individuals over 3 years and relate them to cognitive function. METHODS Neurologically and psychiatrically normal volunteers (n = 40) were examined at baseline and 3 years later with (1)H-MRS in two voxels (frontal white matter n = 29, and occipitoparietal gray matter n = 36) and with detailed neuropsychological assessments. Longitudinal analyses were performed with age, educational level, sex, and white matter hyperintensities (WMH) in voxels as covariates. RESULTS Frontal mI was significantly increased over time in male participants, but all other metabolites were stable over time. Neuropsychological performance was not significantly changed over 3 years, and there was no relationship between change in metabolite levels and change in neuropsychological function. CONCLUSIONS MRS-visible metabolites are stable in elderly persons over 3 years, with the exception of mI which shows an increase. Increasing mI may be a marker of aging or a preclinical neurodegenerative process. MRS changes do not correlate with change in neurocognitive function during aging.
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Affiliation(s)
- Amy J Ross
- School of Psychiatry, University of New South Wales, Sydney, Australia
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Mihara M, Hattori N, Abe K, Sakoda S, Sawada T. Magnetic resonance spectroscopic study of Alzheimer's disease and frontotemporal dementia/Pick complex. Neuroreport 2006; 17:413-6. [PMID: 16514368 DOI: 10.1097/01.wnr.0000203353.52622.05] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Disease-specific metabolic changes in Alzheimer's disease and frontotemporal dementia/Pick complex were examined by proton magnetic resonance spectroscopy at 3.0 T. Spectra were acquired from posterior and anterior cingulate cortices and the parieto-occipital and frontal white matter. This study included eight Alzheimer's disease patients, 10 frontotemporal dementia/Pick complex patients and 14 healthy volunteers. N-acetylaspartate/creatine+phosphocreatine ratio was reduced in the posterior cingulate cortex in the Alzheimer's disease and frontotemporal dementia/Pick complex patients. The Alzheimer's disease patients, however, showed a posterior dominant decrease, whereas the frontotemporal dementia/Pick complex patients showed a frontal predominant decrease. These different distributions of metabolic changes may represent the underlying pathological processes in each disease. Our standardized protocol of proton magnetic resonance spectroscopy measurement may be helpful in differentiating these dementia subtypes.
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Fernández A, García-Segura JM, Ortiz T, Montoya J, Maestú F, Gil-Gregorio P, Campo P, Viaño J. Proton magnetic resonance spectroscopy and magnetoencephalographic estimation of delta dipole density: a combination of techniques that may contribute to the diagnosis of Alzheimer's disease. Dement Geriatr Cogn Disord 2005; 20:169-77. [PMID: 16020946 DOI: 10.1159/000087094] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/07/2005] [Indexed: 11/19/2022] Open
Abstract
Whole-head magnetoencephalographic recordings were obtained from 10 patients with Alzheimer's disease (AD) and 10 healthy controls in a resting position. Spectroscopic examinations were performed by means of a 1.5-tesla whole-body scanner in the temporoparietal regions of both hemispheres. The relationship between (1)H-MRS-based and magnetoencephalography (MEG)-based measures and their conjoined capability to improve the diagnosis of AD were investigated in this study. Logistic regression analyses were performed. Three separated logistic models were calculated for (1)H-MRS-based metabolites, low-frequency magnetic activity, and the combination of both measures. A combined myoinositol/N-acetyl aspartate (mI/NAA)-delta dipole density (DD) model predicted the diagnosis with 90% sensitivity and 100% specificity. Additionally, the combination of temporoparietal mI/NAA and delta DD values explained the variability of individuals' cognitive status. The results support the notion that a multidisciplinary approach may improve the understanding and diagnosis of AD.
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Affiliation(s)
- Alberto Fernández
- Centro de Magnetoencefalografía Dr. Pérez-Modrego, Universidad Complutense de Madrid, Madrid, Spain
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Ackl N, Ising M, Schreiber YA, Atiya M, Sonntag A, Auer DP. Hippocampal metabolic abnormalities in mild cognitive impairment and Alzheimer's disease. Neurosci Lett 2005; 384:23-8. [PMID: 15905028 DOI: 10.1016/j.neulet.2005.04.035] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2004] [Revised: 04/09/2005] [Accepted: 04/13/2005] [Indexed: 11/17/2022]
Abstract
Mild cognitive impairment (MCI) defines a group of otherwise healthy elderly subjects with a markedly elevated risk of developing Alzheimer's disease (AD). In the search for biomarkers of MCI, we assessed whether MCI shares neurochemical abnormalities with AD in areas affected early in the course of the disease. As a secondary study aim, we tested to what extent neurochemical findings reflect neuropsychological deficits. Proton spectroscopy was performed in 19 MCI patients, 18 AD patients and 22 age and gender matched controls (CON) within the parietal gray and white matter (PWM and PGM) and the hippocampus (HIP). The cognitive test battery used included measures compiled by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD). The N-acetyl-aspartate to creatine ratio (NAA/Cr) was significantly reduced in the HIP of MCI and AD compared with CON (p < 0.05). Only AD patients showed parietal abnormalities, namely significantly elevated myoinositol (mI/Cr and mI/NAA) in PGM, reduced NAA/Cr and elevated mI/NAA in PWM. MCI subjects were significantly impaired in categorical verbal fluency (VF) (p < 0.001) and delayed verbal recall (DVR) (p < 0.001). VF was positively correlated with hippocampal NAA/Cr (p < 0.05) and parietal mI/NAA (p < 0.05). In summary, this study demonstrates shared neurobiological hippocampal abnormalities in MCI and AD, whereas parietal lobe neurochemical profiles and functions were normal in MCI. Thus, biological evidence is provided that MCI represents a precursor stage of AD. Moreover, multivoxel 1H MRS may enable an objective staging of the neurodegenerative process underlying the age-dependent cognitive deficits eventually leading to dementia.
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Affiliation(s)
- Nibal Ackl
- Department of Psychiatry, Memory Clinic, Max-Planck-Institute of Psychiatry, Kraepelinstrasse 2-10, 80802 Munich, Germany.
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Kim H, Thompson RB, Hanstock CC, Allen PS. Variability of metabolite yield using STEAM or PRESS sequences in vivo at 3.0 T, illustrated with myo-inositol. Magn Reson Med 2005; 53:760-9. [PMID: 15799042 DOI: 10.1002/mrm.20434] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Using as an example the myo-inositol (mI) band at approximately 3.6 ppm in the proton spectrum from brain, an evaluation is presented that highlights the difficulties of quantifying metabolites with strongly coupled spins with either STEAM or PRESS and demonstrates some advantages of prospective sequence analysis when measuring their concentrations. The analysis emphasizes the variation in coupled-spin signal yield and lineshape, compared with that of uncoupled singlets such as N-acetylaspartate, a variation that differs from one metabolite spin system to another. This difference in variation between a target metabolite (e.g., mI) and its contaminating background metabolites (e.g., glutamate and taurine, etc.) is shown to provide in certain circumstances a substantial reduction in background contamination (both metabolite and macromolecule) while maintaining sufficient signal-to-noise ratio for precise quantification. For example, sequence times are demonstrated, both for STEAM and for PRESS, that, relative to the short echo-time sequences typical in the literature, enhance the signal to metabolite background of the 3.6-ppm band of mI by factors of 1.7 and 1.3, respectively, essentially eliminate the macromolecular baseline, and yet in vivo retain an S/N approximately 10 in both cases.
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Affiliation(s)
- Hyeonjin Kim
- Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta T6G 2G3, Canada
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De Win MML, Jager G, Vervaeke HKE, Schilt T, Reneman L, Booij J, Verhulst FC, Den Heeten GJ, Ramsey NF, Korf DJ, Van den Brink W. The Netherlands XTC Toxicity (NeXT) study: objectives and methods of a study investigating causality, course, and clinical relevance. Int J Methods Psychiatr Res 2005; 14:167-85. [PMID: 16395871 PMCID: PMC6878462 DOI: 10.1002/mpr.6] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
This paper describes the objectives and methods of The Netherlands XTC Toxicity (NeXT) study focussing on the causality, course, and clinical relevance of ecstasy neurotoxicity. Previous studies suggest that ecstasy (3,4 methylene-dioxymethamphetamine, MDMA, XTC) is toxic toward brain serotonin axons, but most of these studies have serious methodological limitations. The current study is a combination of different approaches with three substudies: (1) a crosssectional substudy among heavy ecstasy users and controls with variation in drug use, which will provide information about potential neurotoxic consequences of ecstasy in relation to other drugs; (2) a prospective cohort substudy in ecstasy-naive subjects with high risk for future ecstasy use, which will provide information on the causality and short-term course of ecstasy use and potential neurotoxicity, and (3) a retrospective cohort substudy in lifetime ecstasy users and matched controls of an existing epidemiological sample that will provide information on long-term course and outcome of ecstasy use in the general population. Neurotoxicity is studied using (a) different imaging techniques (beta-CIT SPECT, 1H-MR spectroscopy, diffusion tensor imaging, perfusion weighted imaging and functional magnetic resonance imaging), and (b) neuropsychological and psychiatric assessments of memory, depression, and personality. The combined results will lead to conclusions that can be used in prevention messages, clinical decision making, and the development of an (inter)national ecstasy policy.
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Affiliation(s)
- Maartje M L De Win
- Department of Radiology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
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Abstract
The neurophysiological basis of cognition is relatively unexplained, with most studies reporting weak relationships between cognition and measures of brain function, such as event-related potentials, brain size and cerebral blood flow. Magnetic resonance spectroscopy (MRS) is an in vivo method used to detect neurochemicals within the brain that are relevant to certain brain processes. The most widely used methods are 1H-MRS and 31P-MRS, which detect compounds that contain hydrogen and phosphorus, respectively. Recent studies have shown that the absolute concentrations or ratios of these neurochemicals, in particular N-acetyl aspartate (NAA), which is associated with neuronal viability, correlate with performance on neuropsychological tests or other measures of cognitive function in normal subjects. Many studies in adults and children have shown a relationship between neurometabolite values and cognitive status or extent of cognitive dysfunction in various neurological and neuropsychiatric disorders. We review these studies and conclude that MRS has potential applications for the study of cognitive processes in health and disease and may be used clinically for differential diagnosis, the early detection of pathology and the examination of longitudinal change.
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Affiliation(s)
- Amy J Ross
- School of Psychiatry, University of New South Wales, Kensington, New South Wales 2033, Australia.
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Herminghaus S, Frölich L, Gorriz C, Pilatus U, Dierks T, Wittsack HJ, Lanfermann H, Maurer K, Zanella FE. Brain metabolism in Alzheimer disease and vascular dementia assessed by in vivo proton magnetic resonance spectroscopy. Psychiatry Res 2003; 123:183-90. [PMID: 12928106 DOI: 10.1016/s0925-4927(03)00071-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Proton magnetic resonance spectroscopy (MRS) allows the assessment of various cerebral metabolites non-invasively in vivo. Among 1H MRS-detectable metabolites, N-acetyl-aspartate and N-acetyl-aspartyl-glutamate (tNAA), trimethylamines (TMA), creatine and creatine phosphate (tCr), inositol (Ins) and glutamate (Gla) are of particular interest, since these moieties can be assigned to specific neuronal and glial metabolic pathways, membrane constituents, and energy metabolism. In this study on 94 subjects from a memory clinic population, 1H MRS results (single voxel STEAM: TE 20 ms, TR 1500 ms) on the above metabolites were assessed for five different brain regions in probable vascular dementia (VD), probable Alzheimer's disease (AD), and age-matched healthy controls. In both VD and AD, ratios of tNAA/tCr were decreased, which may be attributed to neuronal atrophy and loss, and Ins/tCr-ratios were increased indicating either enhanced gliosis or alteration of the cerebral inositol metabolism. However, the topographical distribution of the metabolic alterations in both diseases differed, revealing a temporoparietal pattern for AD and a global, subcortically pronounced pattern for VD. Furthermore, patients suffering from vascular dementia (VD) had remarkably enhanced TMA/tCr ratios, potentially due to ongoing degradation of myelin. Thus, the metabolic alterations obtained by 1H MRS in vivo allow insights into the pathophysiology of the different dementias and may be useful for diagnostic classification.
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Affiliation(s)
- Sebastian Herminghaus
- Institute of Neuroradiology, Johann W. Goethe University, Schleusenweg 2-16, Frankfurt/Main 60590, Germany.
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O'Neill J, Schuff N, Marks WJ, Feiwell R, Aminoff MJ, Weiner MW. Quantitative 1H magnetic resonance spectroscopy and MRI of Parkinson's disease. Mov Disord 2002; 17:917-27. [PMID: 12360540 DOI: 10.1002/mds.10214] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Magnetic resonance imaging (MRI) and (1)H magnetic resonance spectroscopy (MRS) of the substantia nigra, basal ganglia, and cerebral cortex were performed on 10 patients with Parkinson's disease (PD) and 13 age-matched, healthy control subjects. Compared to controls, PD patients had approximately 24% lower creatine in the region of the substantia nigra and smaller volumes of the putamen (11%), globus pallidus (16%), and prefrontal cortex (6%; all P < 0.05). No other significant between-group differences were found in nine regions examined. Thus, quantitative MRI may show regional neurodegenerative changes outside the substantia nigra in PD but PD-linked extranigral metabolic abnormalities, if they exist, may be difficult to detect with current (1)H MRS methods. In additional, exploratory tests, volumes of the caudate (r = -0.56), putamen (r = -0.66), and globus pallidus (r = -0.60; all P < 0.05) were negatively correlated with the volume of the substantia nigra pars compacta in controls. In PD these correlations did not hold. Instead, pallidal volume in PD was positively correlated with compacta volume (r = 0.64; P < 0.05). This relationship suggests that basal ganglia volumes may be influenced by dopaminergic innervation from the substantia nigra in normal and PD subjects.
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Affiliation(s)
- Joseph O'Neill
- Magnetic Resonance Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, California, USA.
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Parks MH, Dawant BM, Riddle WR, Hartmann SL, Dietrich MS, Nickel MK, Price RR, Martin PR. Longitudinal Brain Metabolic Characterization of Chronic Alcoholics With Proton Magnetic Resonance Spectroscopy. Alcohol Clin Exp Res 2002. [DOI: 10.1111/j.1530-0277.2002.tb02681.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Cheng LL, Newell K, Mallory AE, Hyman BT, Gonzalez RG. Quantification of neurons in Alzheimer and control brains with ex vivo high resolution magic angle spinning proton magnetic resonance spectroscopy and stereology. Magn Reson Imaging 2002; 20:527-33. [PMID: 12413598 DOI: 10.1016/s0730-725x(02)00512-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Samples from human brains were examined with both stereologic methods for neuronal counting and high resolution magic angle spinning (HRMAS) proton magnetic resonance spectroscopy (1HMRS) for quantification of cellular metabolites. A statistically significant linear correlation between neuronal density and the concentration of N-acetylaspartate (NAA) in the superior temporal sulcus (STS) area was observed. Although NAA has been widely utilized as a neuronal marker in in vivo MRS, an emerging sub-discipline of diagnostic neuroradiology, the experimental proof of the unilateral relationship between NAA and neurons has yet to be confirmed. The observed correlation provides experimental evidence that NAA concentration is proportional to the neuronal density. Metabolite ratios measured from the STS area were compared to those from frontal association cortex for their sensitivities in differentiating Alzheimer disease brains from control brains.
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Affiliation(s)
- Leo Ling Cheng
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
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Abstract
Glucose homeostasis is of paramount concern to the brain since glucose is its primary fuel. Thus, the brain has evolved mechanisms to sense and respond to changes in glucose levels. The efferent aspects of the central nervous system response to hypoglycemia are relatively well understood. In addition, it is accepted that the brain regulates food intake and energy balance. Obesity and diabetes both result from and cause alterations in the central nervous system function. Thus, it is reasonable to hypothesize that the brain also regulates daily glucose homeostasis and energy balance. However, little is known about how the brain actually senses and responds to changes in extracellular glucose. While there are neurons in the brain that change their action potential frequency in response to changes in extracellular glucose, most studies of these neurons have been performed using glucose levels that are outside the physiologic range of extracellular brain glucose. Thus, the physiologic relevance of these glucose-sensing neurons is uncertain. However, recent studies show that glucose-sensing neurons do respond to physiologic changes in extracellular glucose. This review will first investigate the data regarding physiologic glucose levels in the brain. The various subtypes of physiologically relevant glucose-sensing neurons will then be discussed. Based on the relative glucose sensitivity of these subtypes of glucose-sensing neurons, possible roles in the regulation of glucose homeostasis are hypothesized. Finally, the question of whether these neurons are only glucose sensors or whether they play a more integrated role in the regulation of energy balance will be considered.
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Affiliation(s)
- Vanessa H Routh
- Department of Pharmacology and Physiology and Neurosciences, New Jersey Medical School (UMDNJ), 185 South Orange Avenue, Newark, NJ 07103, USA.
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Abstract
OBJECTIVE This paper briefly describes neuroimaging using magnetic resonance spectroscopy (MRS) and provides a systematic review of its application to psychiatric disorders. METHOD A literature review (Index Medicus/Medline) was carried out, as well as a review of other relevant papers and data known to the authors. RESULTS Magnetic resonance spectroscopy is a complex and sophisticated neuroimaging technique that allows reliable and reproducible quantification of brain neurochemistry provided its limitations are respected. In some branches of medicine it is already used clinically, for instance, to diagnose tumours and in psychiatry its applications are gradually extending beyond research. Neurochemical changes have been found in a variety of brain regions in dementia, schizophrenia and affective disorders and promising discoveries have also been made in anxiety disorders. CONCLUSION Magnetic resonance spectroscopy is a non-invasive investigative technique that has provided useful insights into the biochemical basis of many neuropsychiatric disorders. It allows direct measurement, in vivo, of medication levels within the brain and has made it possible to track the neurochemical changes that occur as a consequence of disease and ageing or in response to treatment. It is an extremely useful advance in neuroimaging technology and one that will undoubtedly have many clinical uses in the near future.
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Affiliation(s)
- Gin S Malhi
- Mood Disorders Unit, The Villa, Prince of Wales Hospital, Randwick NSW 2031, Sydney, Australia.
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Wiedermann D, Schuff N, Matson GB, Soher BJ, Du AT, Maudsley AA, Weiner MW. Short echo time multislice proton magnetic resonance spectroscopic imaging in human brain: metabolite distributions and reliability. Magn Reson Imaging 2001; 19:1073-80. [PMID: 11711231 DOI: 10.1016/s0730-725x(01)00441-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Multislice proton magnetic resonance spectroscopic imaging (1H MRSI) at 25 ms echo time was used to measure concentrations of myo-inositol (mI), N-acetylaspartate (NAA), and creatine (Cr) and choline (Cho) in ten normal subjects between 22 and 84 years of age (mean age 44 +/- 18 years). By co-analysis with MRI based tissue segmentation results, metabolite distributions were analyzed for each tissue type and for different brain regions. Measurement reliability was evaluated using intraclass correlation coefficients (ICC). Significant differences in metabolite distributions were found for all metabolites. mI of frontal gray matter was 84% of parietal gray matter and 87% of white matter. NAA of frontal gray matter was 86% of parietal gray matter and 85% of white matter. Cho of frontal gray matter was 125% of parietal gray matter and 59% of white matter and Cho of parietal gray matter was 47% of white matter. Cr of parietal gray matter was 113% of white matter. Reliability was relatively high (ICC from.70 to.93) for all metabolites in white matter and for NAA and Cr in gray matter, though limited (ICC less than.63) for mI and Cho in gray matter. These findings indicate that voxel gray/white matter contributions, regional variations in metabolite concentrations, and reliability limitations must be considered when interpreting 1H MR spectra of the brain.
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Affiliation(s)
- D Wiedermann
- Magnetic Resonance Unit of DVA Medical Center and Department of Radiology, University of California, San Francisco, USA
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Schuff N, Ezekiel F, Gamst AC, Amend DL, Capizzano AA, Maudsley AA, Weiner MW. Region and tissue differences of metabolites in normally aged brain using multislice 1H magnetic resonance spectroscopic imaging. Magn Reson Med 2001; 45:899-907. [PMID: 11323817 PMCID: PMC1851682 DOI: 10.1002/mrm.1119] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Quantitative measurements of regional and tissue specific concentrations of brain metabolites were measured in elderly subjects using multislice proton magnetic resonance spectroscopic imaging ((1)H MRSI). Selective k-space extrapolation and an inversion-recovery sequence were used to minimize lipid contamination and linear regression was used to account for partial volume problems. The technique was applied to measure the concentrations of N-acetyl aspartate (NAA), and creatine (Cr)- and choline (Cho)-containing compounds in cortical gray and white matter, and white matter lesions of the frontal and the parietal lobe in 40 normal elderly subjects (22 females and 18 males, 56-89 years old, mean age 74 +/- 8). NAA was about 15% lower in cortical gray matter and 23% lower in white matter lesions when compared to normal white matter. Cr was 11% higher in cortical gray matter than in white matter, and also about 15% higher in the parietal cortex than in the frontal cortex. Cho was 28% lower in cortical gray matter than in white matter. Furthermore, NAA and Cr changes correlated with age. In conclusion, regional and tissue differences of brain metabolites must be considered in addition to age-related changes when interpreting (1)H MRSI data.
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Affiliation(s)
- N Schuff
- DVA Medical Center, San Francisco, California 94121, USA.
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