1
|
Baranovicova E, Kalenska D, Grendar M, Lehotsky J. Metabolomic Recovery as a Result of Ischemic Preconditioning Was More Pronounced in Hippocampus than in Cortex That Appeared More Sensitive to Metabolomic Blood Components. Metabolites 2021; 11:metabo11080516. [PMID: 34436457 PMCID: PMC8398863 DOI: 10.3390/metabo11080516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/23/2021] [Accepted: 08/03/2021] [Indexed: 01/16/2023] Open
Abstract
The study of an organism's response to ischemia at different levels is essential to understand the mechanism of the injury as well as protection. We used the occlusion of four vessels as an animal model of global cerebral ischemia to investigate metabolic alterations in cerebral cortex, hippocampus, blood plasma, as well as in a remote organ, the heart, in rats undergoing 24 h postischemic reperfusion. By inducing sublethal ischemic stimuli, we focused on endogenous phenomena known as ischemic tolerance that is currently the best known and most effective way of protecting against ischemic injury. NMR spectroscopy was used to analyze relative metabolite levels in homogenates from rats' cerebral cortex, hippocampus, and heart together with deproteinized blood plasma. In individual animals subjected to global cerebral ischemia, relative concentrations of the essential amino acids isoleucine, valine, phenylalanine, and tyrosine in cerebral cortex correlated with those in blood plasma (p < 0.05, or boundary significant p < 0.09). This did not apply for the hippocampus, suggesting a closer relation between ischemic cortex and metabolomic blood components. Hippocampal non-participation on correlation with blood components may emphasize the observed partial or full normalization the post-ischemically altered levels of a number of metabolites in the preconditioned animals. Remarkably, that was observed for cortex to a lesser extent. As a response to the global cerebral ischemia in heart tissue, we observed decreased glutamate and increased 3-hydroxybutyrate. Ischemically induced semi-ketotic state and other changes found in blood plasma partially normalized when ischemic preconditioning was introduced. Some metabolomic changes were so strong that even individual metabolites were able to differentiate between ischemic, ischemically preconditioned, and control brain tissues.
Collapse
Affiliation(s)
- Eva Baranovicova
- Biomedical Center BioMed, Jessenius Faculty of Medicine, Comenius University in Bratislava, Mala Hora 4, 036 01 Martin, Slovakia;
| | - Dagmar Kalenska
- Department of Anatomy, Jessenius Faculty of Medicine, Comenius University in Bratislava, Mala Hora 4, 036 01 Martin, Slovakia;
| | - Marian Grendar
- Biomedical Center BioMed, Bioinformatical Unit, Jessenius Faculty of Medicine, Comenius University in Bratislava, Mala Hora 4, 036 01 Martin, Slovakia;
| | - Jan Lehotsky
- Department of Medical Biochemistry, Jessenius Faculty of Medicine, Comenius University in Bratislava, Mala Hora 4, 036 01 Martin, Slovakia
- Correspondence: ; Tel.: +421-43-2633-442
| |
Collapse
|
2
|
Age differences in brain structural and metabolic responses to binge ethanol exposure in fisher 344 rats. Neuropsychopharmacology 2021; 46:368-379. [PMID: 32580206 PMCID: PMC7852871 DOI: 10.1038/s41386-020-0744-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 02/08/2023]
Abstract
An overarching goal of our research has been to develop a valid animal model of alcoholism with similar imaging phenotypes as those observed in humans with the ultimate objective of assessing the effectiveness of pharmacological agents. In contrast to our findings in humans with alcohol use disorders (AUD), our animal model experiments have not demonstrated enduring brain pathology despite chronic, high ethanol (EtOH) exposure protocols. Relative to healthy controls, older individuals with AUD demonstrate accelerating brain tissue loss with advanced age. Thus, this longitudinally controlled study was conducted in 4-month old (equivalent to ~16-year-old humans) and 17-month old (equivalent to ~45-year-old humans) male and female Fisher 344 rats to test the hypothesis that following equivalent alcohol exposure protocols, older relative to younger animals would exhibit more brain changes as evaluated using in vivo structural magnetic resonance imaging (MRI) and MR spectroscopy (MRS). At baseline, total brain volume as well as the volumes of each of the three constituent tissue types (i.e., cerebral spinal fluid (CSF), gray matter, white matter) were greater in old relative to young rats. Baseline metabolite levels (except for glutathione) were higher in older than younger animals. Effects of binge EtOH exposure on brain volumes and neurometabolites replicated our previous findings in Wistar rats and included ventricular enlargement and reduced MRS-derived creatine levels. Brain changes in response to binge EtOH treatment were more pronounced in young relative to older animals, negating our hypothesis. Higher baseline glutathione levels in female than male rats suggest that female rats are perhaps protected against the more pronounced changes in CSF and gray matter volumes observed in male rats due to superior metabolic homeostasis mechanisms. Additional metabolite changes including low inositol levels in response to high blood alcohol levels support a mechanism of reversible osmolarity disturbances due to temporarily altered brain energy metabolism.
Collapse
|
3
|
Ratai EM, Gilberto González R. Clinical magnetic resonance spectroscopy of the central nervous system. HANDBOOK OF CLINICAL NEUROLOGY 2016; 135:93-116. [PMID: 27432661 DOI: 10.1016/b978-0-444-53485-9.00005-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Proton magnetic resonance spectroscopy (1H MRS) is a noninvasive imaging technique that can easily be added to the conventional magnetic resonance (MR) imaging sequences. Using MRS one can directly compare spectra from pathologic or abnormal tissue and normal tissue. Metabolic changes arising from pathology that can be visualized by MRS may not be apparent from anatomy that can be visualized by conventional MR imaging. In addition, metabolic changes may precede anatomic changes. Thus, MRS is used for diagnostics, to observe disease progression, monitor therapeutic treatments, and to understand the pathogenesis of diseases. MRS may have an important impact on patient management. The purpose of this chapter is to provide practical guidance in the clinical application of MRS of the brain. This chapter provides an overview of MRS-detectable metabolites and their significance. In addition some specific current clinical applications of MRS will be discussed, including brain tumors, inborn errors of metabolism, leukodystrophies, ischemia, epilepsy, and neurodegenerative diseases. The chapter concludes with technical considerations and challenges of clinical MRS.
Collapse
Affiliation(s)
- Eva-Maria Ratai
- Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, and Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, USA.
| | - R Gilberto González
- Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, and Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, USA
| |
Collapse
|
4
|
Lee CS, Chen CY. Reduction ofN-acetyl Aspartate in Bilateral Cerebral Tissue in Relation to Compromised Cerebrovascular Reserve Capacity as Investigated by Proton MR Spectroscopy and Acetazolamide Test. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.201000117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
5
|
The neurochemical profile quantified by in vivo 1H NMR spectroscopy. Neuroimage 2012; 61:342-62. [DOI: 10.1016/j.neuroimage.2011.12.038] [Citation(s) in RCA: 168] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 12/15/2011] [Indexed: 12/13/2022] Open
|
6
|
Kawaguchi H, Hirakawa K, Miyauchi K, Koike K, Ohno Y, Sakamoto A. Pattern recognition analysis of proton nuclear magnetic resonance spectra of brain tissue extracts from rats anesthetized with propofol or isoflurane. PLoS One 2010; 5:e11172. [PMID: 20567596 PMCID: PMC2887427 DOI: 10.1371/journal.pone.0011172] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Accepted: 05/27/2010] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND General anesthesia is routinely used as a surgical procedure and its safety has been endorsed by clinical outcomes; however, its effects at the molecular level have not been elucidated. General anesthetics influence glucose metabolism in the brain. However, the effects of anesthetics on brain metabolites other than those related to glucose have not been well characterized. We used a pattern recognition analysis of proton nuclear magnetic resonance spectra to visualize the changes in holistic brain metabolic phenotypes in response to the widely used intravenous anesthetic propofol and the volatile anesthetic isoflurane. METHODOLOGY/PRINCIPAL FINDINGS Rats were randomized into five groups (n = 7 each group). Propofol and isoflurane were administered to two groups each, for 2 or 6 h. The control group received no anesthesia. Brains were removed directly after anesthesia. Hydrophilic compounds were extracted from excised whole brains and measured by proton nuclear magnetic resonance spectroscopy. All spectral data were processed and analyzed by principal component analysis for comparison of the metabolite profiles. Data were visualized by plotting principal component (PC) scores. In the plots, each point represents an individual sample. The propofol and isoflurane groups were clustered separately on the plots, and this separation was especially pronounced when comparing the 6-h groups. The PC scores of the propofol group were clearly distinct from those of the control group, particularly in the 6-h group, whereas the difference in PC scores was more subtle in the isoflurane group and control groups. CONCLUSIONS/SIGNIFICANCE The results of the present study showed that propofol and isoflurane exerted differential effects on holistic brain metabolism under anesthesia.
Collapse
Affiliation(s)
- Hiroshi Kawaguchi
- Department of Anesthesiology, Nippon Medical School, Bunkyo-ku, Tokyo, Japan.
| | | | | | | | | | | |
Collapse
|
7
|
Crosson B, Ford A, McGregor KM, Meinzer M, Cheshkov S, Li X, Walker-Batson D, Briggs RW. Functional imaging and related techniques: an introduction for rehabilitation researchers. JOURNAL OF REHABILITATION RESEARCH AND DEVELOPMENT 2010; 47:vii-xxxiv. [PMID: 20593321 PMCID: PMC3225087 DOI: 10.1682/jrrd.2010.02.0017] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Functional neuroimaging and related neuroimaging techniques are becoming important tools for rehabilitation research. Functional neuroimaging techniques can be used to determine the effects of brain injury or disease on brain systems related to cognition and behavior and to determine how rehabilitation changes brain systems. These techniques include: functional magnetic resonance imaging (fMRI), positron emission tomography (PET), electroencephalography (EEG), magnetoencephalography (MEG), near infrared spectroscopy (NIRS), and transcranial magnetic stimulation (TMS). Related diffusion weighted magnetic resonance imaging techniques (DWI), including diffusion tensor imaging (DTI) and high angular resolution diffusion imaging (HARDI), can quantify white matter integrity. With the proliferation of these imaging techniques in rehabilitation research, it is critical that rehabilitation researchers, as well as consumers of rehabilitation research, become familiar with neuroimaging techniques, what they can offer, and their strengths and weaknesses The purpose to this review is to provide such an introduction to these neuroimaging techniques.
Collapse
Affiliation(s)
- Bruce Crosson
- VA RR&D Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, Florida
- Department of Clinical & Health Psychology, University of Florida, Gainesville, Florida
| | - Anastasia Ford
- Department of Psychology, University of Florida, Gainesville, Florida
| | - Keith M. McGregor
- VA RR&D Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, Florida
- Department of Psychology, University of Florida, Gainesville, Florida
| | - Marcus Meinzer
- Department of Clinical & Health Psychology, University of Florida, Gainesville, Florida
| | - Sergey Cheshkov
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Xiufeng Li
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas
| | | | - Richard W. Briggs
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
8
|
Lei H, Berthet C, Hirt L, Gruetter R. Evolution of the neurochemical profile after transient focal cerebral ischemia in the mouse brain. J Cereb Blood Flow Metab 2009; 29:811-9. [PMID: 19223915 DOI: 10.1038/jcbfm.2009.8] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Evolution of the neurochemical profile consisting of 19 metabolites after 30 mins of middle cerebral artery occlusion was longitudinally assessed at 3, 8 and 24 h in 6 to 8 microL volumes in the striatum using localized 1H-magnetic resonance spectroscopy at 14.1 T. Profound changes were detected as early as 3 h after ischemia, which include elevated lactate levels in the presence of significant glucose concentrations, decreases in glutamate and a transient twofold glutamine increase, likely to be linked to the excitotoxic release of glutamate and conversion into glial glutamine. Interestingly, decreases in N-acetyl-aspartate (NAA), as well as in taurine, exceeded those in neuronal glutamate, suggesting that the putative neuronal marker NAA is rather a sensitive marker of neuronal viability. With further ischemia evolution, additional, more profound concentration decreases were detected, reflecting a disruption of cellular functions. We conclude that early changes in markers of energy metabolism, glutamate excitotoxicity and neuronal viability can be detected with high precision non-invasively in mice after stroke. Such investigations should lead to a better understanding and insight into the sequential early changes in the brain parenchyma after ischemia, which could be used for identifying new targets for neuroprotection.
Collapse
Affiliation(s)
- Hongxia Lei
- Laboratory of Functional and Metabolic Imaging, Institute of the Physics of Biological System, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | | | | | | |
Collapse
|
9
|
Ashwal S, Obenaus A, Snyder EY. Neuroimaging as a basis for rational stem cell therapy. Pediatr Neurol 2009; 40:227-36. [PMID: 19218036 DOI: 10.1016/j.pediatrneurol.2008.09.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Revised: 09/04/2008] [Accepted: 09/25/2008] [Indexed: 02/02/2023]
Abstract
Neonatal global or focal hypoxic-ischemic brain injury remains a frequent and devastating condition, with serious long-term sequelae. An important issue in any neonatal clinical trial of neuroprotective agents relates to developing accurate measures of injury severity and also suitable measures of the response to treatment. Advanced magnetic resonance imaging techniques can acquire serial and noninvasive data about brain structure, metabolic activity, and the response to injury or treatment. These imaging methods need validation in appropriate animal models for translational research studies in human newborns. This review describes several approaches that use imaging as well as proton magnetic resonance spectroscopy to assess the severity of ischemic injury (e.g., for possible candidate selection) and for monitoring the progression and evolution of injury over time and as an indicator of recovery or response to treatment. Preliminary data are presented on how imaging can be used after neural stem cell implantation to characterize the migration rate, the magnitude of stem cell proliferation, and their final location. Imaging has the potential to allow monitoring of many dimensions of neuroprotective treatments and can be expected to contribute to efficacy and safety when clinical trials using neural stem cells or other neuroprotective agents become available.
Collapse
Affiliation(s)
- Stephen Ashwal
- Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, California 92354, USA.
| | | | | |
Collapse
|
10
|
Douglas RM, Miyasaka N, Takahashi K, Latuszek-Barrantes A, Haddad GG, Hetherington HP. Chronic intermittent but not constant hypoxia decreases NAA/Cr ratios in neonatal mouse hippocampus and thalamus. Am J Physiol Regul Integr Comp Physiol 2006; 292:R1254-9. [PMID: 17082353 DOI: 10.1152/ajpregu.00404.2006] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Chronic constant hypoxia (CCH) and chronic intermittent hypoxia (CIH) are known to have deleterious effects on the central nervous system. Because of the difference in the pattern of hypoxic exposure, it is possible that the pathological outcome would vary. The N-acetyl aspartate/creatine (NAA/Cr) ratio is a reliable marker of neuronal integrity, and this can be noninvasively measured by proton nuclear magnetic resonance spectroscopy. P2 CD1 mouse pups with their dams were exposed to either CCH, where the Fi(O(2)) was maintained at 11% continuously or to CIH, where the Fi(O(2)) was varied between 21 and 11% every 4 min. P30 mice exposed to intermittent hypoxia for 4 wk demonstrated a significant decrease in the NAA/Cr ratio in the hippocampus and thalamus, which was reversed by a subsequent exposure to 4 wk of normoxia. Meanwhile, mice exposed to 4 wk of constant hypoxia did not demonstrate any differences in their NAA/Cr ratios from controls in these brain regions. These results indicate that an intermittent pattern of hypoxic exposure may have a more adverse effect on neuronal function and integrity than a continuous one. The reversal of NAA/Cr levels to baseline during the return to normoxia indicates that therapeutic strategies targeted at alleviating the intermittent hypoxic stress in diseases, such as obstructive sleep apnea, have the potential for inducing significant neurocognitive recovery in these patients.
Collapse
Affiliation(s)
- Robert M Douglas
- Department of Pediatrics, School of Medicine, University of California-San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA.
| | | | | | | | | | | |
Collapse
|
11
|
Weber R, Ramos-Cabrer P, Hoehn M. Present status of magnetic resonance imaging and spectroscopy in animal stroke models. J Cereb Blood Flow Metab 2006; 26:591-604. [PMID: 16292254 DOI: 10.1038/sj.jcbfm.9600241] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Magnetic resonance imaging (MRI) is based on a wide variety of physical parameters, which, in principle, can all influence the image contrast conditions. As these diverse variables are validated by independent physiological, metabolic, hemodynamic, and histological techniques, a physiological MRI evolves. This imaging modality has been successfully applied to experimental stroke studies, covering a broad range of raised questions. In the present review, we present an overview of possible physiological criteria to be studied by in vivo MRI and magnetic resonance spectroscopy, and critically analyze the present limits and future potential of the imaging technique for experimental stroke investigations. The documented applications cover the spectrum from morphological-structural details of the lesion to hemodynamic and metabolic alterations, inflammatory reaction, evaluation of thrombolytic treatment, studies on recovery of functional brain activation by functional MRI, and, finally, the most recent applications of exploring stem cells for regenerative therapy.
Collapse
Affiliation(s)
- Ralph Weber
- In-vivo-NMR-Laboratory, Max-Planck-Institute for Neurological Research, Cologne, Germany
| | | | | |
Collapse
|
12
|
Dixon JC, Cady EB, Priest AN, Thornton JS, Peebles DM. Growth restriction and the cerebral metabolic response to acute hypoxia of chick embryos in-ovo: a proton magnetic resonance spectroscopy study. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2005; 160:203-10. [PMID: 16223529 DOI: 10.1016/j.devbrainres.2005.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2005] [Revised: 09/06/2005] [Accepted: 09/09/2005] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Perinatal brain injury is more common in growth-restricted (GR) than normally grown (NG) fetuses. This study addresses the hypothesis that chronic oxygen and substrate deprivation during pregnancy will engender an abnormal fetal cerebral metabolic response to acute hypoxia. METHOD Cerebral metabolite resonance amplitudes relative to that of creatine were measured by proton magnetic resonance spectroscopy in chick embryos on day 19 of incubation. Measurements were obtained before, during and after acute hypoxia (8% ambient oxygen concentration for 44 min) in NG and GR embryos (10% albumen extracted day 0 and 14% oxygen exposure from day 10 of incubation). RESULTS In both NG and GR embryos, the cerebral lactate/creatine increased during acute hypoxia and slowly recovered after restoration of normoxia. However, the mean (+/-SD) increase in lactate/creatine was significantly less in GR compared to NG embryos (0.51 +/- 0.36 vs. 0.94 +/- 0.36; P = 0.02, t test). Alanine increased during acute hypoxia in NG but not GR embryos. Mean beta-hydroxybutyrate was increased only in GR embryos (0.63 +/- 0.01 vs. 0.22 +/- 0.01; P < 0.001, ANOVA). CONCLUSIONS Acute hypoxia increases cerebral lactate and alanine in NG chick embryos; these increases are reduced by pre-exposure to substrate deprivation and chronic hypoxia.
Collapse
Affiliation(s)
- James C Dixon
- Department of Obstetrics and Gynaecology, University College London, 86-96 Chenies Mews, London WC1E 6HX, UK
| | | | | | | | | |
Collapse
|
13
|
Chang SL, Cloak CC, Malellari L, Chang L. The effects of repeated endotoxin exposure on rat brain metabolites as measured by ex vivo 1HMRS. J Neuroimmunol 2005; 166:39-46. [PMID: 15996758 PMCID: PMC4899044 DOI: 10.1016/j.jneuroim.2005.04.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 04/15/2005] [Accepted: 04/29/2005] [Indexed: 10/25/2022]
Abstract
Abnormalities in brain chemistry induced by acute or chronic treatment with LPS were studied in the rat model. Ex vivo brain metabolites were measured using proton magnetic resonance spectroscopy, whereas serum corticosterone levels were determined using radioimmunoassay. We observed increased lactate levels in all measured brain regions and decreased choline in the hypothalamus after chronic LPS treatment. Acute LPS treatment led to an elevation of corticosterone, whereas chronic LPS treatment led to attenuation of the HPA response. These findings suggest that chronic inflammation induced by LPS could lead to cell loss/dysfunction, and hence, desensitization of the HPA axis, particularly in the hypothalamus.
Collapse
Affiliation(s)
- Sulie L Chang
- Department of Biology, Seton Hall University, 400 South Orange Avenue, South Orange, NJ 07079, USA.
| | | | | | | |
Collapse
|
14
|
Macrì MA, D'Alessandro N, Di Giulio C, Di Iorio P, Di Luzio S, Giuliani P, Bianchi G, Esposito E. Regional changes in the metabolite profile after long-term hypoxia-ischemia in brains of young and aged rats: a quantitative proton MRS study. Neurobiol Aging 2005; 27:98-104. [PMID: 16298245 DOI: 10.1016/j.neurobiolaging.2005.01.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2004] [Revised: 12/21/2004] [Accepted: 01/04/2005] [Indexed: 11/19/2022]
Abstract
Quantitative proton magnetic resonance spectroscopy (MRS) was used to determine region-specific metabolic changes in young and aged animals subjected to a long-term hypoxic-ischemic injury. Focal ischemia, which was studied as an experimental stroke model, was induced in 3- and 24-month-old rats by unilateral common carotid artery occlusion associated with 24 h of hypoxia. Eight metabolites were quantified from extracts in three different brain regions (hippocampus, frontoparietal and occipital cortices) from both the ipsilateral and contralateral sides. Our findings showed significant differences in lactate and myo-inositol concentration values in the hippocampus of the aged rats as compared to the same area of the young adult group under normoxic conditions. After hypoxia-ischemia (HI), the most relevant changes in metabolite concentrations were found in the hippocampal region of both young and aged groups as compared to their age-matched controls. Of the three brain areas under investigation, the hippocampus proved to be particularly susceptible to the prolonged hypoxia-ischemia perturbation. The effects were more evident in the aged animals.
Collapse
Affiliation(s)
- M A Macrì
- Dipartimento di Medicina Sperimentale e Patologia, Università La Sapienza di Roma, Roma, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Jensen JE, Frederick BD, Wang L, Brown J, Renshaw PF. Two-dimensional, J-resolved spectroscopic imaging of GABA at 4 Tesla in the human brain. Magn Reson Med 2005; 54:783-8. [DOI: 10.1002/mrm.20644] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
16
|
Méric P, Autret G, Doan BT, Gillet B, Sébrié C, Beloeil JC. In vivo 2D magnetic resonance spectroscopy of small animals. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2004; 17:317-38. [PMID: 15625585 DOI: 10.1007/s10334-004-0084-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Revised: 11/02/2004] [Accepted: 11/02/2004] [Indexed: 01/05/2023]
Abstract
Localized in vivo NMR spectroscopy, chemical shift imaging or multi-voxel spectroscopy are potentially useful tools in small animals that are complementary to MRI, adding biochemical information to the mainly anatomical data provided by imaging of water protons. However the contribution of such methods remains hampered by the low spectral resolution of the in vivo 1D spectra. Two-dimensional methods widely developed for in vitro studies have been proposed as suitable approaches to overcome these limitations in resolution. The different homonuclear and heteronuclear sequences adapted to in vivo studies are reviewed. Their specific contributions to the spectral resolution of spectroscopic data and their limitations for in vivo investigations are discussed. The applications to experimental models of pathological processes or pharmacological treatment in mainly brain and muscle are presented. According to their combined sensitivity, acquisition duration and spatial resolution, the heteronuclear 2D experiments, which are mainly used for 1H detected-13C spectroscopy after administration of 13C-labeled compounds, appear to be less efficient than 1H detected-13C 1D methods at high field. However, the applications of 2D proton homonuclear methods show that they remain the best tools for in vivo studies when an improved resolution is required.
Collapse
Affiliation(s)
- P Méric
- Laboratoire de RMN Biologique, ICSN-CNRS, Avenue de la Terrasse, 91198, Gif sur Yvette, France.
| | | | | | | | | | | |
Collapse
|
17
|
Schwarcz A, Natt O, Watanabe T, Boretius S, Frahm J, Michaelis T. Localized proton MRS of cerebral metabolite profiles in different mouse strains. Magn Reson Med 2003; 49:822-7. [PMID: 12704764 DOI: 10.1002/mrm.10445] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Localized proton MR spectroscopy (MRS) was used to quantify cerebral metabolite concentrations in NMRI (n = 8), BALB/c (n = 7), and C57BL/6 (n = 8) mice in vivo and 1 hr after global irreversible ischemia (2.35 T, STEAM, TR/TE/TM = 6000/20/10 ms, 4 x 3 x 4 mm(3) volume, corrections for cerebrospinal fluid). Anatomical MRI and proton MRS revealed significant differences of the C57BL/6 strain in comparison with both BALB/c and NMRI mice. While MRI volumetry yielded larger ventricular spaces of the C57BL/6 strain, proton MRS resulted in elevated concentrations of N-acetylaspartate (tNAA), creatine and phosphocreatine (tCr), choline-containing compounds (Cho), glucose (Glc), and lactate (Lac) relative to BALB/c mice and elevated Glc relative to NMRI mice. Apart from the expected decrease of Glc and increase of Lac 1 hr post mortem, C57BL/6 mice presented with significant reductions of tNAA, tCr, and Cho, whereas these metabolites remained unchanged in BALB/c and NMRI mice. The results support the hypothesis that the more pronounced vulnerability of C57BL/6 mice to brain ischemia is linked to strain-dependent differences of the cerebral energy metabolism.
Collapse
Affiliation(s)
- Attila Schwarcz
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany
| | | | | | | | | | | |
Collapse
|
18
|
Ziegler A, Gillet B, Beloeil JC, Macher JP, Décorps M, Nédelec JF. Localized 2D correlation spectroscopy in human brain at 3 T. MAGMA (NEW YORK, N.Y.) 2002; 14:45-9. [PMID: 11796252 DOI: 10.1007/bf02668186] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The purpose of this study was to acquire a localized 2D (two-dimensional) 1H correlation spectrum, in a volume of interest reasonably small, and within an experiment time compatible with clinical applications. A modified PRESS technique has been used. The last 180 degrees pulse of the PRESS sequence has been converted into a 90 degrees pulse for both refocusing and coherence transfer. 2D correlation spectroscopy was performed on healthy volunteers in a clinical magnet, at 3 T, within 34 min, for a voxel size of 27 cm3. This result makes it possible to consider clinical applications.
Collapse
Affiliation(s)
- Anne Ziegler
- Unité mixte INSERM, Université J. Fourier U438 'RMN Bioclinique', LRC CEA, CHU pavillon B, BP 217, 38043 Cedex 9, Grenoble, France.
| | | | | | | | | | | |
Collapse
|
19
|
Hoehn M, Nicolay K, Franke C, van der Sanden B. Application of magnetic resonance to animal models of cerebral ischemia. J Magn Reson Imaging 2001; 14:491-509. [PMID: 11747001 DOI: 10.1002/jmri.1213] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The present review has been compiled to highlight the role of magnetic resonance imaging (MRI) and MR spectroscopy (MRS) for the investigation of cerebral ischemia in the animal experimental field of basic research. We have focused on stroke investigations analyzing the pathomechanisms of the disease evolution and on new advances in both nuclear MR (NMR) methodology or genetic engineering of transgenic animals for the study of complex molecular relationships and causes of the disease. Furthermore, we have tried to include metabolic and genetic aspects, as well as the application of functional imaging, for the investigation of the disturbance or restitution of functional brain activation under pathological conditions as relates to controlled animal experiments.
Collapse
Affiliation(s)
- M Hoehn
- Max-Planck-Institute for Neurological Research, Cologne, Germany. mathias.mpin-koeln.mpg.de
| | | | | | | |
Collapse
|
20
|
Delmas F, Beloeil JC, van der Sanden BP, Nicolay K, Gillet B. Two-voxel localization sequence for in vivo two-dimensional homonuclear correlation spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2001; 149:119-125. [PMID: 11273760 DOI: 10.1006/jmre.2000.2280] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The combination of localized 2D 1H MR correlation spectroscopy and Hadamard encoding allows the simultaneous acquisition of multiple volumes of interest without an increase in the experimental duration, compared to single-voxel acquisition. In the present study, 2D correlation spectra were acquired simultaneously within 20 to 40 min in two voxels located in each hemisphere of the rat brain. An intervoxel distance of 20% of the voxel size was sufficient to limit spatial contamination. The following cerebral metabolites gave detectable crosspeaks: N-acetylaspartate, the glutamate/glutamine pool, aspartate, phosphoethanolamine, glucose, glutathione, taurine, myo-inositols, lactate, threonine, gamma-aminobutyric acid, and alanine. Most of the metabolites were measured without contamination of other resonances.
Collapse
Affiliation(s)
- F Delmas
- Laboratoire de RMN Biologique, ICSN-CNRS, Gif sur Yvette, 91198, France
| | | | | | | | | |
Collapse
|
21
|
Ke Y, Cohen BM, Bang JY, Yang M, Renshaw PF. Assessment of GABA concentration in human brain using two-dimensional proton magnetic resonance spectroscopy. Psychiatry Res 2000; 100:169-78. [PMID: 11120443 DOI: 10.1016/s0925-4927(00)00075-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A quantitative method to assess in vivo brain gamma-aminobutyric acid (GABA) levels is proposed using a J-resolved, two-dimensional (2D) magnetic resonance spectroscopy (MRS) technique. Localized, J-resolved 2D MR spectra were obtained from a 12-cm(3) voxel in the occipital lobe of 36 healthy volunteers (18 male and 18 female, age: 25.1+/-4.8 years). Based on phantom measurements, a GABA resonance peak located at 2.94 ppm, 7.45 Hz, in J-resolved 2D MRS overlaps the least with other resonance peaks which arise from N-acetylaspartate, choline, creatine, glutamate and glutamine. Measurements of this resonance peak yield in vivo GABA concentrations of 1.01+/-0.36 micromol/cm(3) for male and 1.16+/-0.43 micromol/cm(3) for female volunteers, without correction for T1 and T2 relaxation effects. These results are in good agreement with previously reported data and suggest that, with further development, 2D MRS may provide a practical means to estimate the concentration of this important neurotransmitter.
Collapse
Affiliation(s)
- Y Ke
- McLean Hospital, Brain Imaging Center, Department of Psychiatry, Harvard Medical School, 115 Mill Street, Belmont, MA , 02478-9106, USA
| | | | | | | | | |
Collapse
|
22
|
Abstract
Proton NMR chemical shift and J-coupling values are presented for 35 metabolites that can be detected by in vivo or in vitro NMR studies of mammalian brain. Measurements were obtained using high-field NMR spectra of metabolites in solution, under conditions typical for normal physiological temperature and pH. This information is presented with an accuracy that is suitable for computer simulation of metabolite spectra to be used as basis functions of a parametric spectral analysis procedure. This procedure is verified by the analysis of a rat brain extract spectrum, using the measured spectral parameters. In addition, the metabolite structures and example spectra are presented, and clinical applications and MR spectroscopic measurements of these metabolites are reviewed.
Collapse
Affiliation(s)
- V Govindaraju
- Department of Radiology, University of California San Francisco and DVA Medical Center, 4150 Clement St (114M), San Francisco, CA 94121, USA
| | | | | |
Collapse
|
23
|
Madl JE, Royer SM. Glutamate in synaptic terminals is reduced by lack of glucose but not hypoxia in rat hippocampal slices. Neuroscience 1999; 94:417-30. [PMID: 10579205 DOI: 10.1016/s0306-4522(99)00340-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Although excessive release of the neurotransmitter glutamate contributes to ischemic neuronal damage, immunocytochemical studies have not found a loss of glutamate from ischemic axon terminals. We examined the effects of two components of ischemia, hypoxia and hypoglycemia, on glutamate loss from rat hippocampal slices. In vitro hypoglycemia induced by incubation for 1 h without glucose depleted 50% of glutamate from slices when ATP levels were about 5 nmol/mg protein. Hypoxic slices aerated with N2 reached similar ATP levels without significant glutamate depletion. To induce 50% glutamate losses with chemical hypoxia, ATP had to be depleted to < 1 nmol/mg protein. Immunocytochemical staining indicated that glutamate-like immunoreactivity was reduced throughout slices by hypoglycemia. Hypoxia decreased glutamate-like immunoreactivity in neuronal perikarya and dendrites of pyramidal cells and granule cells. However, in contrast to hypoglycemia, hypoxia maintained or increased glutamate-like immunoreactivity in many terminals. Hypoxia and hypoglycemia induced similar, ATP-dependent releases of glutamate into supernatants, which could account for only part of the hypoglycemic losses. The additional hypoglycemic losses were consistent with increased catabolism of glutamate. Glutamate losses from hypoglycemic terminals were reduced by blockade of aspartate aminotransferase or the tricarboxylic acid cycle. Exogenous glutamate increased glutamate in hypoglycemic slices to hypoxic levels and returned glutamate-like immunoreactivity to terminals, suggesting that terminals maintained glutamate uptake during metabolic insults. Hypoglycemia induces a large loss of glutamate that does not occur during hypoxia. The greater loss of glutamate from terminals during hypoglycemia is consistent with increased metabolism of glutamate via aspartate aminotransferase and not increased release of glutamate. Continued uptake of glutamate by hypoxic terminals may help to maintain their levels of glutamate. Hypoglycemic metabolism of glutamate may decrease pathologic glutamate release and contribute to the prolonged neurologic abnormalities associated with recovery from hypoglycemia.
Collapse
Affiliation(s)
- J E Madl
- Department of Anatomy and Neurobiology, Colorado State University, Fort Collins 80523, USA.
| | | |
Collapse
|
24
|
Braun KP, van Eijsden P, Vandertop WP, de Graaf RA, Gooskens RH, Tulleken KA, Nicolay K. Cerebral metabolism in experimental hydrocephalus: an in vivo 1H and 31P magnetic resonance spectroscopy study. J Neurosurg 1999; 91:660-8. [PMID: 10507389 DOI: 10.3171/jns.1999.91.4.0660] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Brain damage in patients with hydrocephalus is caused by mechanical forces and cerebral ischemia. The severity and localization of impaired cerebral blood flow and metabolism are still largely unknown. Magnetic resonance (MR) spectroscopy offers the opportunity to investigate cerebral energy metabolism and neuronal damage noninvasively and longitudinally. Previous 1H MR spectroscopy studies have shown an increased lactate resonance that is suggestive of anaerobic glycolysis. The aim of this study was to assess cerebral damage and energy metabolism in kaolin-induced hydrocephalus in adult rats by using in vivo 1H and 31P MR spectroscopy. The presence of lactate was correlated with high-energy phosphate metabolism and intracellular pH. The measurement of relative concentrations of N-acetyl aspartate (NAA), choline (Cho), and total creatine (tCr) served to assess neuronal damage. METHODS Hydrocephalus was induced in adult rats by surgical injection of kaolin into the cisterna magna. Magnetic resonance studies, using a 4.7-tesla magnet, were performed longitudinally in hydrocephalic animals at 1 (10 rats), 8 (six rats), and 16 weeks (six rats) thereafter, as well as in eight control animals. To evaluate ventricular size and white matter edema T2-weighted MR imaging was performed. The 1H MR spectra were acquired from a 240-microl voxel, positioned centrally in the brain, followed by localized 31P MR spectroscopy on a two-dimensional column that contained the entire brain but virtually no extracranial muscles. The 1H and 31P MR spectroscopy peak ratios were calculated after fitting the spectra in the time domain, intracellular pH was estimated from the inorganic phosphate (Pi) chemical shift, and T2 relaxation times of 1H metabolites were determined from the signal decay at increasing echo times. CONCLUSIONS In hydrocephalic rats, ventricular expansion stabilized after 8 weeks. White matter edema was most pronounced during acute hydrocephalus. Lactate peaks were increased at all time points, without a decrease in phosphocreatine (PCr)/Pi and PCr/adenosine triphosphate (ATP) peak ratios, or pH. Possibly lactate production is restricted to periventricular brain tissue, followed by its accumulation in cerebrospinal fluid, which is supported by the long lactate T2 relaxation time. Alternatively, lactate production may precede impairment of ATP homeostasis. The NAA/Cho and tCr/Cho ratios significantly decreased during the acute and chronic stages of hydrocephalus. These changes were not caused by alterations in metabolite T2 relaxation time. The decreases in the NAA/Cho and tCr/Cho ratios implicate neuronal loss/dysfunction or changes in membrane phospholipid metabolism, as in myelin damage or gliosis. It is suggested that 1H MR spectroscopy can be of additional value in the assessment of energy metabolism and cerebral damage in clinical hydrocephalus.
Collapse
Affiliation(s)
- K P Braun
- Department of Neurology, University Medical Center Utrecht, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
25
|
Abstract
Noninvasive detection of taurine, an important amino acid involved in numerous physiological processes, by in vivo (1)H magnetic resonance (MR) spectroscopy is complicated by severe overlap of the taurine resonances with those of a number of other metabolites. Unambiguous differentiation of the taurine resonances requires spectral editing. In this study, the development of a localized spectral editing technique based on double-quantum filtering optimized for in vivo detection of taurine is described. The sequence recovers the taurine signal while substantially eliminating overlapping resonances and provides excellent three-dimensional spatial localization. The performance of the sequence is demonstrated both in phantoms and in rat brain in vivo. Magn Reson Med 42:454-460, 1999.
Collapse
Affiliation(s)
- H Lei
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada
| | | |
Collapse
|
26
|
Gasparovic C, King D, Feeney DM. Metabolism in single rat brain slices measured by magnetic resonance spectroscopy. BRAIN RESEARCH. BRAIN RESEARCH PROTOCOLS 1999; 4:97-102. [PMID: 10234457 DOI: 10.1016/s1385-299x(99)00010-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Nuclear magnetic resonance spectroscopy (MRS) has been used to study brain biochemistry in superfused brain slice preparations for over a decade. However, unlike techniques that monitor electrical activity, ion fluxes, or the release of radio-labeled compounds in single brain slices, MRS studies have required samples composed of several slices and inherently poor anatomical specificity in order to achieve adequate signal-to-noise levels, spectral resolution, or, in the case of 1H MRS, a high degree of artifact-free water signal suppression. We report that gradient-enhanced 1H MRS techniques combined with a simple slice positioning and perfusion technique yield high-quality spectra from single 400 microns rat forebrain or neocortical-hippocampal slices within 15 min of data acquisition time. Spectra of comparable quality were obtained from samples with three neocortical or three hippocampal slices within the same time frame. The assessment of anaerobic energy metabolism in single slices by 1H MRS is also demonstrated. In addition to greater anatomical resolution in studies on brain slice biochemistry, single slice MRS also presents the possibility of correlating, within the same slice, 1H MRS-detectable metabolite levels with other physiological measurements commonly performed on single brain slices.
Collapse
Affiliation(s)
- C Gasparovic
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque 87131, USA.
| | | | | |
Collapse
|
27
|
Abstract
Short-echo gradient-enhanced nuclear magnetic resonance (NMR) spectroscopy was utilized to identify mobile lipids in perfused neonate and juvenile rat brain slices. Lipid signals were present at low levels within 1 hr of tissue preparation and increased with time under standard perfusion conditions and in the presence of high phosphocreatine and low lactate levels. Both one- and two-dimensional NMR spectra demonstrate peaks consistent with the generation of free fatty acids or neutral lipids following tissue trauma. The present work demonstrates that injury-induced mobile lipids may make appreciable contributions to regions of brain tissue spectra that have recently been assigned to lactate or polypeptides alone.
Collapse
Affiliation(s)
- C Gasparovic
- Department of Neurosciences and Center for Non-Invasive Diagnosis, University of New Mexico School of Medicine, Albuquerque, USA.
| | | |
Collapse
|