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Maková M, Kašparová S, Tvrdík T, Noguera M, Belovičová K, Csatlosová K, Dubovický M. Mirtazapine modulates Glutamate and GABA levels in the animal model of maternal depression. MRI and 1H MRS study in female rats. Behav Brain Res 2023; 442:114296. [PMID: 36641082 DOI: 10.1016/j.bbr.2023.114296] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 12/19/2022] [Accepted: 01/10/2023] [Indexed: 01/13/2023]
Abstract
We aimed to determine, using in vivo magnetic resonance, whether maternal depression induced by chronic unpredictable stress (CUS) in the pre-gestational period in female rats would be evidenced by structural or neurometabolic changes in the hippocampal region of the brain. At the same time, appropriate behavioral tests were also administered after a relatively long two-month period of a stress paradigm. The objective of the study was not only to study an animal model of CUS using magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRS) focused on the hippocampus, but also to use this technique to verify the effectiveness of mirtazapine antidepressant treatment. In the group with CUS, we found a significant decrease in the relative concentration of γ-aminobutyric acid (GABA/tCr) and glutamate+glutamine (Glx/tCr) compared to the control group, while we did not observe any statistically significant change in hippocampal volumes. Moreover, the forced swim test revealed an increase in depression-like behavior. The most important finding was the return of GABA/tCr and Glx/tCr levels to control levels during mirtazapine treatment; however, behavioral tests did not demonstrate any effects from mirtazapine treatment. In vivo1H MRS confirmed mirtazapine modulation of CUS in an animal model more robustly than behavioral tests.
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Affiliation(s)
- Marianna Maková
- Slovak University of Technology in Bratislava, Central Laboratory of Faculty of Food and Chemical Technology, Radlinského 9, Bratislava 81237, Slovak Republic.
| | - Svatava Kašparová
- Slovak University of Technology in Bratislava, Central Laboratory of Faculty of Food and Chemical Technology, Radlinského 9, Bratislava 81237, Slovak Republic.
| | - Tomáš Tvrdík
- Slovak University of Technology in Bratislava, Central Laboratory of Faculty of Food and Chemical Technology, Radlinského 9, Bratislava 81237, Slovak Republic; Department of Radiology, Faculty of Medicine of Comenius University in Bratislava, Slovak Medical University and University Hospital Bratislava, Limbová 12, Bratislava 83303, Slovak Republic.
| | - Mireia Noguera
- Centre of Experimental Medicine, Institute of Experimental Pharmacology and Toxicology, Slovak Academy Sciences, Dúbravská cesta 9, Bratislava 84104, Slovak Republic.
| | - Kristína Belovičová
- Centre of Experimental Medicine, Institute of Experimental Pharmacology and Toxicology, Slovak Academy Sciences, Dúbravská cesta 9, Bratislava 84104, Slovak Republic.
| | - Kristína Csatlosová
- Centre of Experimental Medicine, Institute of Experimental Pharmacology and Toxicology, Slovak Academy Sciences, Dúbravská cesta 9, Bratislava 84104, Slovak Republic.
| | - Michal Dubovický
- Centre of Experimental Medicine, Institute of Experimental Pharmacology and Toxicology, Slovak Academy Sciences, Dúbravská cesta 9, Bratislava 84104, Slovak Republic.
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Manzhurtsev AV, Yakovlev AN, Bulanov PA, Menshchikov PE, Ublinskiy MV, Melnikov IA, Akhadov TA, Semenova NA. Macromolecular-Suppressed GABA-Edited MR Spectroscopy in the Posterior Cingulate Cortex of Patients With Acute Mild Traumatic Brain Injury. J Magn Reson Imaging 2022; 57:1433-1442. [PMID: 36053885 DOI: 10.1002/jmri.28410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/12/2022] [Accepted: 08/12/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Mild traumatic brain injury (mTBI) causes a number of molecular and cellular alterations. There is evidence of an imbalance between the main excitatory (glutamate, Glu) and the main inhibitory (gamma-aminobutyric acid [GABA]) neurotransmitters following mTBI. In vivo human GABA-Glu balance studies following mTBI are sparse. PURPOSE To investigate the effect of acute mTBI on the GABA concentration measured in the posterior cingulate cortex (PCC) of pediatric patients by using the macromolecular (MM)-suppressed GABA J-editing technique. STUDY TYPE Prospective patient and phantom. PARTICIPANTS A total of 14 pediatric patients (mean age 16.0 ± 1.7) with acute mTBI (<3 days after trauma; Glasgow Coma Scale 15) and 16 healthy volunteers (mean age 16.9 ± 2.8). Phantom: 524 cm3 sphere containing 10 mM glycine, 10 mM GABA. FIELD STRENGTH/SEQUENCE A 3 T, MEGA-PRESS pulse sequence. ASSESSMENT GABA spectra were processed in Gannet software. MM-suppressed GABA editing efficiency was derived from the phantom study. Absolute GABA and glutamate + glutamine (Glx) concentrations were quantified using different types of correction and compared between groups. N-acetyl aspartate (NAA) and choline (Cho) levels relative to tCr were also compared. STATISTICAL TESTS Shapiro-Wilk test, Mann-Whitney U test, Student t-test, Pearson or Spearman correlations. P < 0.01 was considered statistically significant. RESULTS The MM-suppressed GABA editing efficiency was 0.63. GABA signal fit error was <16% for all participants. The GABA concentration in the PCC of the mTBI group was significantly different from that in healthy controls: GABA/tCr was higher by 27%, absolute GABA concentration with different types of correction was higher by ≈17%. No significant differences were observed in Glx concentrations (P ≥ 0.32) or in Glx/tCr (P ≥ 0.1), NAA/tCr (P = 0.55), and Cho/tCr levels (P = 0.85). DATA CONCLUSION We report an increase in the GABA concentration in the PCC region in acute mTBI pediatric patients. This may suggest activation of GABA synthesis and impairment of the GABAergic system after acute mTBI. EVIDENCE LEVEL 3 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Andrei V Manzhurtsev
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation.,Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences, Moscow, Russian Federation.,Moscow State University, Moscow, Russian Federation
| | - Alexey N Yakovlev
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation.,Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences, Moscow, Russian Federation.,N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, Moscow, Russian Federation
| | - Petr A Bulanov
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation.,Moscow State University, Moscow, Russian Federation.,Philips Healthcare, Moscow, Russian Federation
| | - Petr E Menshchikov
- Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences, Moscow, Russian Federation.,Philips Healthcare, Moscow, Russian Federation
| | - Maxim V Ublinskiy
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation.,Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences, Moscow, Russian Federation
| | - Ilya A Melnikov
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation
| | - Tolib A Akhadov
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation.,Moscow State University, Moscow, Russian Federation
| | - Natalia A Semenova
- Clinical and Research Institute of Emergency Pediatric Surgery and Trauma, Moscow, Russian Federation.,Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences, Moscow, Russian Federation.,Moscow State University, Moscow, Russian Federation.,N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, Moscow, Russian Federation
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3
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Rideaux R, Ehrhardt SE, Wards Y, Filmer HL, Jin J, Deelchand DK, Marjańska M, Mattingley JB, Dux PE. On the relationship between GABA+ and glutamate across the brain. Neuroimage 2022; 257:119273. [PMID: 35526748 PMCID: PMC9924060 DOI: 10.1016/j.neuroimage.2022.119273] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/13/2022] [Accepted: 04/29/2022] [Indexed: 01/27/2023] Open
Abstract
Equilibrium between excitation and inhibition (E/I balance) is key to healthy brain function. Conversely, disruption of normal E/I balance has been implicated in a range of central neurological pathologies. Magnetic resonance spectroscopy (MRS) provides a non-invasive means of quantifying in vivo concentrations of excitatory and inhibitory neurotransmitters, which could be used as diagnostic biomarkers. Using the ratio of excitatory and inhibitory neurotransmitters as an index of E/I balance is common practice in MRS work, but recent studies have shown inconsistent evidence for the validity of this proxy. This is underscored by the fact that different measures are often used in calculating E/I balance such as glutamate and Glx (glutamate and glutamine). Here we used a large MRS dataset obtained at ultra-high field (7 T) measured from 193 healthy young adults and focused on two brain regions - prefrontal and occipital cortex - to resolve this inconsistency. We find evidence that there is an inter-individual common ratio between GABA+ (γ-aminobutyric acid and macromolecules) and Glx in the occipital, but not prefrontal cortex. We further replicate the prefrontal result in a legacy dataset (n = 78) measured at high-field (3 T) strength. By contrast, with ultra-high field MRS data, we find extreme evidence that there is a common ratio between GABA+ and glutamate in both prefrontal and occipital cortices, which cannot be explained by participant demographics, signal quality, fractional tissue volume, or other metabolite concentrations. These results are consistent with previous electrophysiological and theoretical work supporting E/I balance. Our findings indicate that MRS-detected GABA+ and glutamate (but not Glx), are a reliable measure of E/I balance .
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Affiliation(s)
- Reuben Rideaux
- Queensland Brain Institute, The University of Queensland, St Lucia, Australia.
| | - Shane E Ehrhardt
- School of Psychology, The University of Queensland, St Lucia, Australia
| | - Yohan Wards
- School of Psychology, The University of Queensland, St Lucia, Australia
| | - Hannah L Filmer
- School of Psychology, The University of Queensland, St Lucia, Australia
| | - Jin Jin
- Siemens Healthcare Pty Ltd, Brisbane, Australia; Center for Advanced Imaging, The University of Queensland, St Lucia, Australia
| | - Dinesh K Deelchand
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - Małgorzata Marjańska
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - Jason B Mattingley
- Queensland Brain Institute, The University of Queensland, St Lucia, Australia; School of Psychology, The University of Queensland, St Lucia, Australia
| | - Paul E Dux
- School of Psychology, The University of Queensland, St Lucia, Australia
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Rideaux R. No balance between glutamate+glutamine and GABA+ in visual or motor cortices of the human brain: A magnetic resonance spectroscopy study. Neuroimage 2021; 237:118191. [PMID: 34023450 DOI: 10.1016/j.neuroimage.2021.118191] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 04/27/2021] [Accepted: 05/19/2021] [Indexed: 12/28/2022] Open
Abstract
Theoretical work, supported by electrophysiological evidence, asserts that a balance between excitation and inhibition (E/I) is critical for healthy brain function. In magnetic resonance spectroscopy (MRS) studies, the ratio of excitatory (glutamate) and inhibitory (γ-aminobutyric acid, GABA) neurotransmitters is often used as a proxy for this E/I balance. Recent MRS work found a positive correlation between GABA+ and Glx (glutamate+glutamine) in medial parietal cortex, providing validation for this proxy and supporting the link between the E/I balance observed in electrophysiology and that detected with MRS. Here we assess the same relationship, between GABA+ and Glx, in visual and motor cortices of male and female human participants. We find moderate to strong evidence that there is no positive correlation between these neurotransmitters in either location. We show this holds true when controlling for a range of other factors (i.e., demographics, signal quality, tissue composition, other neurochemicals) and regardless of the state of neural activity (i.e., resting/active). These results show that there is no brain-wide balance between excitatory and inhibitory neurotransmitters and indicates a dissociation between the E/I balance observed in electrophysiological work and the ratio of MRS-detected neurotransmitters.
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Affiliation(s)
- Reuben Rideaux
- Department of Psychology, Downing Street, University of Cambridge, UK; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia.
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5
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Rideaux R, Mikkelsen M, Edden RAE. Comparison of methods for spectral alignment and signal modelling of GABA-edited MR spectroscopy data. Neuroimage 2021; 232:117900. [PMID: 33652146 PMCID: PMC8245134 DOI: 10.1016/j.neuroimage.2021.117900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/10/2021] [Accepted: 02/17/2021] [Indexed: 01/25/2023] Open
Abstract
Many methods exist for aligning and quantifying magnetic resonance spectroscopy (MRS) data to measure in vivo γ-aminobutyric acid (GABA). Research comparing the performance of these methods is scarce partly due to the lack of ground-truth measurements. The concentration of GABA is approximately two times higher in grey matter than in white matter. Here we use the proportion of grey matter within the MRS voxel as a proxy for ground-truth GABA concentration to compare the performance of four spectral alignment methods (i.e., retrospective frequency and phase drift correction) and six GABA signal modelling methods. We analyse a diverse dataset of 432 MEGA-PRESS scans targeting multiple brain regions and find that alignment to the creatine (Cr) signal produces GABA+ estimates that account for approximately twice as much of the variance in grey matter as the next best performing alignment method. Further, Cr alignment was the most robust, producing the fewest outliers. By contrast, all signal modelling methods, except for the single-Lorentzian model, performed similarly well. Our results suggest that variability in performance is primarily caused by differences in the zero-order phase estimated by each alignment method, rather than frequency, resulting from first-order phase offsets within subspectra. These results provide support for Cr alignment as the optimal method of processing MEGA-PRESS to quantify GABA. However, more broadly, they demonstrate a method of benchmarking quantification of in vivo metabolite concentration from other MRS sequences.
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Affiliation(s)
- Reuben Rideaux
- Department of Psychology, Downing Street, University of Cambridge, UK.
| | - Mark Mikkelsen
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States; F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States
| | - Richard A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States; F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States
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6
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Dienel GA. Stop the rot. Enzyme inactivation at brain harvest prevents artifacts: A guide for preservation of the in vivo concentrations of brain constituents. J Neurochem 2021; 158:1007-1031. [PMID: 33636013 DOI: 10.1111/jnc.15293] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/30/2020] [Accepted: 01/05/2021] [Indexed: 12/25/2022]
Abstract
Post-mortem metabolism is widely recognized to cause rapid and prolonged changes in the concentrations of multiple classes of compounds in brain, that is, they are labile. Post-mortem changes from levels in living brain include components of pathways of metabolism of glucose and energy compounds, amino acids, lipids, signaling molecules, neuropeptides, phosphoproteins, and proteins. Methods that stop enzyme activity at brain harvest were developed almost 50 years ago and have been extensively used in studies of brain functions and diseases. Unfortunately, these methods are not commonly used to harvest brain tissue for mass spectrometry-based metabolomic studies or for imaging mass spectrometry studies (IMS, also called mass spectrometry imaging, MSI, or matrix-assisted laser desorption/ionization-MSI, MALDI-MSI). Instead these studies commonly kill animals, decapitate, dissect out brain and regions of interest if needed, then 'snap' freeze the tissue to stop enzymatic activity after harvest, with post-mortem intervals typically ranging from ~0.5 to 3 min. To increase awareness of the importance of stopping metabolism at harvest and preventing the unnecessary complications of not doing so, this commentary provides examples of labile metabolites and the magnitudes of their post-mortem changes in concentrations during brain harvest. Brain harvest methods that stop metabolism at harvest eliminate post-mortem enzymatic activities and can improve characterization of normal and diseased brain. In addition, metabolomic studies would be improved by reporting absolute units of concentration along with normalized peak areas or fold changes. Then reported values can be evaluated and compared with the extensive neurochemical literature to help prevent reporting of artifactual data.
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Affiliation(s)
- Gerald A Dienel
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.,Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, NM, USA
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7
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Hsu CH, Lin S, Ho AC, Johnson TD, Wang PC, Scafidi J, Tu TW. Comparison of in vivo and in situ detection of hippocampal metabolites in mouse brain using 1 H-MRS. NMR IN BIOMEDICINE 2021; 34:e4451. [PMID: 33258202 PMCID: PMC8214416 DOI: 10.1002/nbm.4451] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 10/04/2020] [Accepted: 11/06/2020] [Indexed: 05/25/2023]
Abstract
The study of cerebral metabolites relies heavily on detection methods and sample preparation. Animal experiments in vivo require anesthetic agents that can alter brain metabolism, whereas ex vivo experiments demand appropriate fixation methods to preserve the tissue from rapid postmortem degradation. In this study, the metabolic profiles of mouse hippocampi using proton magnetic resonance spectroscopy (1 H-MRS) were compared in vivo and in situ with or without focused beam microwave irradiation (FBMI) fixation. Ten major brain metabolites, including lactate (Lac), N-acetylaspartate (NAA), total choline (tCho), myo-inositol (mIns), glutamine (Gln), glutamate (Glu), aminobutyric acid (GABA), glutathione (GSH), total creatine (tCr) and taurine (Tau), were analyzed using LCModel. After FBMI fixation, the concentrations of Lac, tCho and mIns were comparable with those obtained in vivo under isoflurane, whereas other metabolites were significantly lower. Except for a decrease in NAA and an increase in Tau, all the other metabolites remained stable over 41 hours in FBMI-fixed brains. Without FBMI, the concentrations of mIns (before 2 hours), tCho and GABA were close to those measured in vivo. However, higher Lac (P < .01) and lower NAA, Gln, Glu, GSH, tCr and Tau were observed (P < .01). NAA, Gln, Glu, GSH, tCr and Tau exhibited good temporal stability for at least 20 hours in the unfixed brain, whereas a linear increase of tCho, mIns and GABA was observed. Possible mechanisms of postmortem degradation are discussed. Our results indicate that a proper fixation method is required for in situ detection depending on the targeted metabolites of specific interests in the brain.
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Affiliation(s)
- Chao-Hsiung Hsu
- Molecular Imaging Laboratory, Department of Radiology, Howard University, Washington, DC, USA
| | - Stephen Lin
- Molecular Imaging Laboratory, Department of Radiology, Howard University, Washington, DC, USA
| | - Ai-Chen Ho
- Molecular Imaging Laboratory, Department of Radiology, Howard University, Washington, DC, USA
- Department of Pharmacotherapy and Outcomes Science, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, USA
| | - T. Derek Johnson
- Center for Neuroscience Research, Department of Neurology, Children’s National Hospital, Washington, DC, USA
| | - Paul C. Wang
- Molecular Imaging Laboratory, Department of Radiology, Howard University, Washington, DC, USA
- Department of Electrical Engineering, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Joseph Scafidi
- Center for Neuroscience Research, Department of Neurology, Children’s National Hospital, Washington, DC, USA
| | - Tsang-Wei Tu
- Molecular Imaging Laboratory, Department of Radiology, Howard University, Washington, DC, USA
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8
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Häni A, Diserens G, Oevermann A, Vermathen P, Precht C. Sampling Method Affects HR-MAS NMR Spectra of Healthy Caprine Brain Biopsies. Metabolites 2021; 11:metabo11010038. [PMID: 33419191 PMCID: PMC7825498 DOI: 10.3390/metabo11010038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/29/2020] [Accepted: 01/04/2021] [Indexed: 11/16/2022] Open
Abstract
The metabolic profiling of tissue biopsies using high-resolution–magic angle spinning (HR-MAS) 1H nuclear magnetic resonance (NMR) spectroscopy may be influenced by experimental factors such as the sampling method. Therefore, we compared the effects of two different sampling methods on the metabolome of brain tissue obtained from the brainstem and thalamus of healthy goats by 1H HR-MAS NMR spectroscopy—in vivo-harvested biopsy by a minimally invasive stereotactic approach compared with postmortem-harvested sample by dissection with a scalpel. Lactate and creatine were elevated, and choline-containing compounds were altered in the postmortem compared to the in vivo-harvested samples, demonstrating rapid changes most likely due to sample ischemia. In addition, in the brainstem samples acetate and inositols, and in the thalamus samples ƴ-aminobutyric acid, were relatively increased postmortem, demonstrating regional differences in tissue degradation. In conclusion, in vivo-harvested brain biopsies show different metabolic alterations compared to postmortem-harvested samples, reflecting less tissue degradation. Sampling method and brain region should be taken into account in the analysis of metabolic profiles. To be as close as possible to the actual situation in the living individual, it is desirable to use brain samples obtained by stereotactic biopsy whenever possible.
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Affiliation(s)
- Annakatrin Häni
- Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Länggassstr. 124, 3012 Bern, Switzerland;
| | - Gaëlle Diserens
- Departments of BioMedical Research and Radiology, University and Inselspital Bern, sitem-insel AG, Freiburgstr. 3, 3010 Bern, Switzerland; (G.D.); (P.V.)
| | - Anna Oevermann
- NeuroCenter, Division of Neurological Sciences, Department of Clinical Research and Veterinary Public Health, Vetsuisse Faculty, University of Bern, Bremgartenstr. 109a, 3012 Bern, Switzerland;
| | - Peter Vermathen
- Departments of BioMedical Research and Radiology, University and Inselspital Bern, sitem-insel AG, Freiburgstr. 3, 3010 Bern, Switzerland; (G.D.); (P.V.)
| | - Christina Precht
- Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Länggassstr. 124, 3012 Bern, Switzerland;
- Correspondence: ; Tel.: +41-31-631-2918
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9
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Hartnell D, Andrews W, Smith N, Jiang H, McAllum E, Rajan R, Colbourne F, Fitzgerald M, Lam V, Takechi R, Pushie MJ, Kelly ME, Hackett MJ. A Review of ex vivo Elemental Mapping Methods to Directly Image Changes in the Homeostasis of Diffusible Ions (Na +, K +, Mg 2 +, Ca 2 +, Cl -) Within Brain Tissue. Front Neurosci 2020; 13:1415. [PMID: 32038130 PMCID: PMC6987141 DOI: 10.3389/fnins.2019.01415] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 12/16/2019] [Indexed: 12/11/2022] Open
Abstract
Diffusible ions (Na+, K+, Mg2+, Ca2+, Cl-) are vital for healthy function of all cells, especially brain cells. Unfortunately, the diffusible nature of these ions renders them difficult to study with traditional microscopy in situ within ex vivo brain tissue sections. This mini-review examines the recent progress in the field, using direct elemental mapping techniques to study ion homeostasis during normal brain physiology and pathophysiology, through measurement of ion distribution and concentration in ex vivo brain tissue sections. The mini-review examines the advantages and limitations of specific techniques: proton induced X-ray emission (PIXE), X-ray fluorescence microscopy (XFM), secondary ion mass spectrometry (SIMS), laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and the sample preparation requirements to study diffusible ions with these methods.
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Affiliation(s)
- David Hartnell
- School of Molecular and Life Sciences, Faculty of Science and Engineering, Curtin University, Perth, WA, Australia
- Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- Curtin Institute for Functional Molecules and Interfaces, Curtin University, Perth, WA, Australia
| | - Wendy Andrews
- School of Molecular and Life Sciences, Faculty of Science and Engineering, Curtin University, Perth, WA, Australia
- Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- Curtin Institute for Functional Molecules and Interfaces, Curtin University, Perth, WA, Australia
| | - Nicole Smith
- School of Molecular Sciences, Faculty of Science, University of Western Australia, Perth, WA, Australia
| | - Haibo Jiang
- School of Molecular Sciences, Faculty of Science, University of Western Australia, Perth, WA, Australia
| | - Erin McAllum
- Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
| | - Ramesh Rajan
- Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Frederick Colbourne
- Department of Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AL, Canada
- Department of Psychology, Faculty of Arts, University of Alberta, Edmonton, AL, Canada
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- School of Biological Sciences, University of Western Australia, Perth, WA, Australia
- Perron Institute for Neurological and Translational Science, Perth, WA, Australia
| | - Virginie Lam
- Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- School of Public Health, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | - Ryusuke Takechi
- Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- School of Public Health, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | - M. Jake Pushie
- Department of Surgery, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Michael E. Kelly
- Department of Surgery, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Mark J. Hackett
- School of Molecular and Life Sciences, Faculty of Science and Engineering, Curtin University, Perth, WA, Australia
- Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- Curtin Institute for Functional Molecules and Interfaces, Curtin University, Perth, WA, Australia
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10
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Bertalan G, Klein C, Schreyer S, Steiner B, Kreft B, Tzschätzsch H, de Schellenberger AA, Nieminen-Kelhä M, Braun J, Guo J, Sack I. Biomechanical properties of the hypoxic and dying brain quantified by magnetic resonance elastography. Acta Biomater 2020; 101:395-402. [PMID: 31726251 DOI: 10.1016/j.actbio.2019.11.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 11/01/2019] [Accepted: 11/06/2019] [Indexed: 12/24/2022]
Abstract
Respiratory arrest is a major life-threatening condition leading to cessation of vital functions and hypoxic-anoxic injury of the brain. The progressive structural tissue changes characterizing the dying brain biophysically are unknown. Here we use noninvasive magnetic resonance elastography to show that biomechanical tissue properties are highly sensitive to alterations in the brain in the critical period before death. Our findings demonstrate that brain stiffness increases after respiratory arrest even when cardiac function is still preserved. Within 5 min of cardiac arrest, cerebral stiffness further increases by up to 30%. This early mechanical signature of the dying brain can be explained by water accumulation and redistribution from extracellular spaces into cells. These processes, together, increase interstitial and intracellular pressure as revealed by magnetic resonance spectroscopy and diffusion-weighted imaging. Our data suggest that the fast response of cerebral stiffness to respiratory arrest enables the monitoring of life-threatening brain pathology using noninvasive in vivo imaging. STATEMENT OF SIGNIFICANCE: Hypoxia-anoxia is a life-threatening condition eventually leading to brain death. Therefore, monitoring vital brain functions in patients at risk is urgently required during emergency care or treatment of acute brain damage due to insufficient oxygen supply. In mouse model of hypoxia-anoxia, we have shown for the first time that biophysical tissue parameters such as brain stiffness changed markedly during the process of death.
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Affiliation(s)
- Gergely Bertalan
- Department of Radiology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Charlotte Klein
- Department of Neurology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Stefanie Schreyer
- Department of Neurology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Barbara Steiner
- Department of Neurology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Bernhard Kreft
- Department of Radiology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Heiko Tzschätzsch
- Department of Radiology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Angela Ariza de Schellenberger
- Department of Radiology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Melina Nieminen-Kelhä
- Department of Neurosurgery, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Jürgen Braun
- Institute for Medical Informatics, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Jing Guo
- Department of Radiology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany.
| | - Ingolf Sack
- Department of Radiology, Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
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11
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Jirak D, Ziolkowska N, Turnovcova K, Karova K, Sykova E, Jendelova P, Romanyuk N. Metabolic Changes in Focal Brain Ischemia in Rats Treated With Human Induced Pluripotent Stem Cell-Derived Neural Precursors Confirm the Beneficial Effect of Transplanted Cells. Front Neurol 2019; 10:1074. [PMID: 31695666 PMCID: PMC6818685 DOI: 10.3389/fneur.2019.01074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/23/2019] [Indexed: 12/12/2022] Open
Abstract
There is currently no treatment for restoring lost neurological function after stroke. A growing number of studies have highlighted the potential of stem cells. However, the mechanisms underlying their beneficial effect have yet to be explored in sufficient detail. In this study, we transplanted human induced pluripotent stem cell-derived neural precursors (iPSC-NPs) in rat temporary middle cerebral artery occlusion (MCAO) model. Using magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) we monitored the effect of cells and assessed lesion volume and metabolite changes in the brain. We monitored concentration changes of myo-inositol (Ins), Taurine (Tau), Glycerophosphocholine+Phosphocholine (GPC+PCh), N-acetyl-aspartate+N-acetyl-aspartyl-glutamate (NAA+NAAG), Creatine+Phosphocreatine (Cr+PCr), and Glutamate+Glutamine (Glu+Gln) in the brains of control and iPSC-NP-transplanted rats. Based on initial lesion size, animals were divided into small lesion and big lesion groups. In the small lesion control group (SCL), lesion size after 4 months was three times smaller than initial measurements. In the small lesion iPSC-NP-treated group, lesion volume decreased after 1 month and then increased after 4 months. Although animals with small lesions significantly improved their motor skills after iPSC-NP transplantation, animals with big lesions showed no improvement. However, our MRI data demonstrate that in the big lesion iPSC-NP-treated (BTL) group, lesion size increased only up until 1 month after MCAO induction and then decreased. In contrast, in the big lesion control group, lesion size increased throughout the whole experiment. Significantly higher concentrations of Ins, Tau, GPC+PCh, NAA+NAAG, Cr+PCr, and Glu+Gln were found in in contralateral hemisphere in BTL animals 4 months after cell injection. Lesion volume decreased at this time point. Spectroscopic results of metabolite concentrations in lesion correlated with volumetric measurements of lesion, with the highest negative correlation observed for NAA+NAAG. Altogether, our results suggest that iPSC-NP transplantation decreases lesion volume and regulates metabolite concentrations within the normal range expected in healthy tissue. Further research into the ability of iPSC-NPs to differentiate into tissue-specific neurons and its effect on the long-term restoration of lesioned tissue is necessary.
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Affiliation(s)
- Daniel Jirak
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czechia
- First Faculty of Medicine, Institute of Biophysics and Informatics, Charles University, Prague, Czechia
- Faculty of Health Studies, Technical University of Liberec, Liberec, Czechia
| | - Natalia Ziolkowska
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czechia
- First Faculty of Medicine, Institute of Biophysics and Informatics, Charles University, Prague, Czechia
| | - Karolina Turnovcova
- Department of Neuroregeneration, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czechia
| | - Kristyna Karova
- Department of Neuroregeneration, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czechia
| | - Eva Sykova
- Department of Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czechia
| | - Pavla Jendelova
- Department of Neuroregeneration, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czechia
- Department of Neuroscience, Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Nataliya Romanyuk
- Department of Neuroregeneration, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czechia
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12
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Heimer J, Gascho D, Chatzaraki V, Knaute DF, Sterzik V, Martinez RM, Thali MJ, Zoelch N. Postmortem 1H-MRS—Detection of Ketone Bodies and Glucose in Diabetic Ketoacidosis. Int J Legal Med 2017; 132:593-598. [DOI: 10.1007/s00414-017-1741-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 11/13/2017] [Indexed: 12/15/2022]
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13
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Choi JE, Park Y. EPA and DHA, but not ALA, have antidepressant effects with 17β-estradiol injection via regulation of a neurobiological system in ovariectomized rats. J Nutr Biochem 2017; 49:101-109. [DOI: 10.1016/j.jnutbio.2017.07.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 06/28/2017] [Accepted: 07/19/2017] [Indexed: 12/29/2022]
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14
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Hu ZL, Xia HH, Yang YJ, Zheng H, Zhao LC, Chen YC, Zhuge QC, Xia NZ, Gao HC, Chen WJ. Metabolic alterations in the rat cerebellum following acute middle cerebral artery occlusion, as determined by 1H NMR spectroscopy. Mol Med Rep 2017; 17:531-541. [PMID: 29115616 DOI: 10.3892/mmr.2017.7918] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/11/2017] [Indexed: 01/06/2023] Open
Abstract
Supratentorial focal ischemia may reduce cerebral blood volume and cerebellar glucose metabolic rate contralateral to the region of ischemia. The present study investigated the effects of middle cerebral artery occlusion (MCAO) on cerebral metabolism in the ischemic cerebral hemisphere and the non‑ischemic cerebellum in rats 1, 3, 9 and 24 h following ischemia using ex vivo proton nuclear magnetic resonance (1H NMR) spectroscopy. The results demonstrated that focal ischemia induced increases in the levels of lactate and alanine, and a decrease in succinate, as early as 1 h following ischemia in the left cerebral hemisphere and the right cerebellum. A continuous increase in lactate levels and decrease in creatine levels were detected in both cerebral areas 3 and 24 h post‑MCAO. The most obvious difference between the two cerebral areas was that there was no statistically significant difference in N‑acetyl aspartate (NAA) levels in the right cerebellum at all time points; however, the amino acid levels of NAA in the left cerebral hemisphere were markedly decreased 3, 9 and 24 h post‑MCAO. In addition, an obvious increase in glutamine was observed in the right and left cerebellum at 3, 9 and 24 h post‑MCAO. Furthermore, the present study demonstrated that γ‑aminobutyric acid levels were decreased at 1 h in the left and right cerebellum and were evidently increased at 24 h in the right cerebellum post‑MCAO. In conclusion, supratentorial ischemia has been indicated to affect the activities of the non‑ischemic contralateral cerebellum. Therefore, these results suggested that an NMR‑based metabonomic approach may be used as a potential means to elucidate cerebral and cerebellar metabolism following MCAO, which may help improve understanding regarding cerebral infarction at a molecular level. Ex vivo 1H NMR analysis may be useful for the assessment of clinical biopsies.
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Affiliation(s)
- Zi-Long Hu
- Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University/Zhejiang Province Key Laboratory of Aging and Neurological Disorder Research, Wenzhou, Zhejiang 325000, P.R. China
| | - Huan-Huan Xia
- Institute of Metabonomics and Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Yun-Jun Yang
- Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University/Zhejiang Province Key Laboratory of Aging and Neurological Disorder Research, Wenzhou, Zhejiang 325000, P.R. China
| | - Hong Zheng
- Institute of Metabonomics and Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Liang-Cai Zhao
- Institute of Metabonomics and Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Yong-Chun Chen
- Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University/Zhejiang Province Key Laboratory of Aging and Neurological Disorder Research, Wenzhou, Zhejiang 325000, P.R. China
| | - Qi-Chuan Zhuge
- Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University/Zhejiang Province Key Laboratory of Aging and Neurological Disorder Research, Wenzhou, Zhejiang 325000, P.R. China
| | - Neng-Zhi Xia
- Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University/Zhejiang Province Key Laboratory of Aging and Neurological Disorder Research, Wenzhou, Zhejiang 325000, P.R. China
| | - Hong-Chang Gao
- Institute of Metabonomics and Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Wei-Jian Chen
- Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University/Zhejiang Province Key Laboratory of Aging and Neurological Disorder Research, Wenzhou, Zhejiang 325000, P.R. China
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15
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Zhang Z, Shemesh N, Frydman L. Efficient spectroscopic imaging by an optimized encoding of pretargeted resonances. Magn Reson Med 2017; 77:511-519. [PMID: 26910285 PMCID: PMC5184843 DOI: 10.1002/mrm.26161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 01/11/2016] [Accepted: 01/20/2016] [Indexed: 12/25/2022]
Abstract
PURPOSE A "relaxation-enhanced" (RE) approach to acquire in vivo localized spectra with flat baselines and good sensitivity has been recently proposed. As RE MR spectroscopy (MRS) targets a subset of a priori known resonances, new possibilities arise to acquire spectroscopic imaging data in faster, more efficient manners. This is hereby illustrated by Spectroscopically Encoded Chemical Shift Imaging (SECSI). METHODS SECSI delivers spectral/spatial correlations by collecting gradient echo trains whose timings are defined by the shifts of the resonances to be disentangled. Condition number considerations allow one to unravel these image contributions for various sites by a simple matrix inversion. The efficiency of the ensuing method is high enough to enable a sampling of additional spatial axes by means of their phase encoding in spin-echo trains. RESULTS The one-dimensional (1D) spectral / 2D spatial SECSI acquisitions were implemented on phantom, ex vivo, and in vivo models. In all cases, quality site-resolved images were obtained. The experimentally observed enhancements were consistent with theoretical signal-to-noise ratio derivations. CONCLUSION While still bound by MRSI's sensitivity limitations, a novel spectroscopic imaging protocol exploiting a priori information, selective excitations and multiple echo encodings, was proposed and demonstrated. The method is promising when dealing with high T2 / T2* ratios, sparse data, or hyperpolarization studies. Magn Reson Med 77:511-519, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Zhiyong Zhang
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, Fujian 361005, China
| | - Noam Shemesh
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
- Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Lucio Frydman
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
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16
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Kumar V, Chang H, Reiter DA, Bradley DP, Belury M, McCormack SE, Raman SV. Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle. J Vis Exp 2017. [PMID: 28190054 DOI: 10.3791/54977] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo and noninvasively in humans via phosphorus-31 magnetic resonance spectroscopy (31PMRS). However, the approach has not been widely adopted in translational and clinical research, with variations in methodology and limited guidance from the literature. Increased optimization, standardization, and dissemination of methods for in vivo 31PMRS would facilitate the development of targeted therapies to improve OXPHOS capacity and could ultimately favorably impact cardiovascular health. 31PMRS produces a noninvasive, in vivo measure of OXPHOS capacity in human skeletal muscle, as opposed to alternative measures obtained from explanted and potentially altered mitochondria via muscle biopsy. It relies upon only modest additional instrumentation beyond what is already in place on magnetic resonance scanners available for clinical and translational research at most institutions. In this work, we outline a method to measure in vivo skeletal muscle OXPHOS. The technique is demonstrated using a 1.5 Tesla whole-body MR scanner equipped with the suitable hardware and software for 31PMRS, and we explain a simple and robust protocol for in-magnet resistive exercise to rapidly fatigue the quadriceps muscle. Reproducibility and feasibility are demonstrated in volunteers as well as subjects over a wide range of functional capacities.
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Affiliation(s)
- Vidhya Kumar
- Davis Heart and Lung Research Institute, The Ohio State University
| | - Henry Chang
- Davis Heart and Lung Research Institute, The Ohio State University
| | - David A Reiter
- Laboratory of Clinical Investigation, National Institute on Aging
| | - David P Bradley
- Division of Endocrinology, Diabetes and Metabolism, The Ohio State University
| | - Martha Belury
- Department of Human Sciences, Human Nutrition, The Ohio State University
| | - Shana E McCormack
- Division of Endocrinology and Diabetes, Department of Pediatrics, University of Pennsylvania
| | - Subha V Raman
- Davis Heart and Lung Research Institute, The Ohio State University;
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17
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Cabré R, Jové M, Naudí A, Ayala V, Piñol-Ripoll G, Gil-Villar MP, Dominguez-Gonzalez M, Obis È, Berdun R, Mota-Martorell N, Portero-Otin M, Ferrer I, Pamplona R. Specific Metabolomics Adaptations Define a Differential Regional Vulnerability in the Adult Human Cerebral Cortex. Front Mol Neurosci 2016; 9:138. [PMID: 28008307 PMCID: PMC5143679 DOI: 10.3389/fnmol.2016.00138] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/22/2016] [Indexed: 12/17/2022] Open
Abstract
Brain neurons offer diverse responses to stresses and detrimental factors during development and aging, and as a result of both neurodegenerative and neuropsychiatric disorders. This multiplicity of responses can be ascribed to the great diversity among neuronal populations. Here we have determined the metabolomic profile of three healthy adult human brain regions-entorhinal cortex, hippocampus, and frontal cortex-using mass spectrometry-based technologies. Our results show the existence of a lessened energy demand, mitochondrial stress, and lower one-carbon metabolism (particularly restricted to the methionine cycle) specifically in frontal cortex. These findings, along with the better antioxidant capacity and lower mTOR signaling also seen in frontal cortex, suggest that this brain region is especially resistant to stress compared to the entorhinal cortex and hippocampus, which are more vulnerable regions. Globally, our results show the presence of specific metabolomics adaptations in three mature, healthy human brain regions, confirming the existence of cross-regional differences in cell vulnerability in the human cerebral cortex.
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Affiliation(s)
- Rosanna Cabré
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Mariona Jové
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Alba Naudí
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Victoria Ayala
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | | | | | | | - Èlia Obis
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Rebeca Berdun
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Natalia Mota-Martorell
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Manuel Portero-Otin
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
| | - Isidre Ferrer
- Institute of Neuropathology, University of BarcelonaBarcelona, Spain; Center for Biomedical Research on Neurodegenerative Diseases, Instituto de Salud Carlos III - ISCIIIBarcelona, Spain
| | - Reinald Pamplona
- Department of Experimental Medicine, University of Lleida-Institute for Research in Biomedicine of Lleida (UdL-IRBLleida) Lleida, Spain
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18
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Mikkelsen M, Singh KD, Brealy JA, Linden DEJ, Evans CJ. Quantification of γ-aminobutyric acid (GABA) in 1 H MRS volumes composed heterogeneously of grey and white matter. NMR IN BIOMEDICINE 2016; 29:1644-1655. [PMID: 27687518 DOI: 10.1002/nbm.3622] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/15/2016] [Accepted: 08/17/2016] [Indexed: 06/06/2023]
Abstract
The quantification of γ-aminobutyric acid (GABA) concentration using localised MRS suffers from partial volume effects related to differences in the intrinsic concentration of GABA in grey (GM) and white (WM) matter. These differences can be represented as a ratio between intrinsic GABA in GM and WM: rM . Individual differences in GM tissue volume can therefore potentially drive apparent concentration differences. Here, a quantification method that corrects for these effects is formulated and empirically validated. Quantification using tissue water as an internal concentration reference has been described previously. Partial volume effects attributed to rM can be accounted for by incorporating into this established method an additional multiplicative correction factor based on measured or literature values of rM weighted by the proportion of GM and WM within tissue-segmented MRS volumes. Simulations were performed to test the sensitivity of this correction using different assumptions of rM taken from previous studies. The tissue correction method was then validated by applying it to an independent dataset of in vivo GABA measurements using an empirically measured value of rM . It was shown that incorrect assumptions of rM can lead to overcorrection and inflation of GABA concentration measurements quantified in volumes composed predominantly of WM. For the independent dataset, GABA concentration was linearly related to GM tissue volume when only the water signal was corrected for partial volume effects. Performing a full correction that additionally accounts for partial volume effects ascribed to rM successfully removed this dependence. With an appropriate assumption of the ratio of intrinsic GABA concentration in GM and WM, GABA measurements can be corrected for partial volume effects, potentially leading to a reduction in between-participant variance, increased power in statistical tests and better discriminability of true effects.
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Affiliation(s)
- Mark Mikkelsen
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK.
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Krish D Singh
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
| | - Jennifer A Brealy
- MRC Centre for Neuropsychiatric Genetics and Genomics, Division of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff, UK
| | - David E J Linden
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
- MRC Centre for Neuropsychiatric Genetics and Genomics, Division of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff, UK
| | - C John Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
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19
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Harris AD, Puts NAJ, Edden RAE. Tissue correction for GABA-edited MRS: Considerations of voxel composition, tissue segmentation, and tissue relaxations. J Magn Reson Imaging 2015; 42:1431-40. [PMID: 26172043 DOI: 10.1002/jmri.24903] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 03/18/2015] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To develop a tissue correction for GABA-edited magnetic resonance spectroscopy (MRS) that appropriately addresses differences in voxel gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) fractions. MATERIALS AND METHODS Simulations compared the performance of tissue correction approaches. Corrections were then applied to in vivo data from 16 healthy volunteers, acquired at 3T. GM, WM, and CSF fractions were determined from T1 -weighted images. Corrections for CSF content, GM/WM GABA content, and water relaxation of the three compartments are combined into a single, fully corrected measurement. RESULTS Simulations show that CSF correction increases the dependence of GABA measurements on GM/WM fraction, by an amount equal to the fraction of CSF. Furthermore, GM correction substantially (and nonlinearly) increases the dependence of GABA measurements on GM/WM fraction, for example, by a factor of over four when the voxel GM tissue fraction is 50%. At this tissue fraction, GABA is overestimated by a factor of 1.5. For the in vivo data, correcting for voxel composition increased measured GABA values (P < 0.001 for all regions), but did not reduce intersubject variance (P > 0.5 for all regions). Corrected GABA values differ significantly based on the segmentation procedure used (P < 0.0001) and tissue parameter assumptions made (P < 0.0001). CONCLUSION We introduce a comprehensive tissue correction factor that adjusts GABA measurements to correct for different voxel compositions of GM, WM, and CSF.
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Affiliation(s)
- Ashley D Harris
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA.,F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Nicolaas A J Puts
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA.,F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Richard A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA.,F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
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20
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Brix MK, Ersland L, Hugdahl K, Grüner R, Posserud MB, Hammar Å, Craven AR, Noeske R, Evans CJ, Walker HB, Midtvedt T, Beyer MK. "Brain MR spectroscopy in autism spectrum disorder-the GABA excitatory/inhibitory imbalance theory revisited". Front Hum Neurosci 2015; 9:365. [PMID: 26157380 PMCID: PMC4475903 DOI: 10.3389/fnhum.2015.00365] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 06/08/2015] [Indexed: 12/27/2022] Open
Abstract
Magnetic resonance spectroscopy (MRS) from voxels placed in the left anterior cingulate cortex (ACC) was measured from 14 boys with Autism Spectrum Disorder (ASD) and 24 gender and age-matched typically developing (TD) control group. Our main aims were to compare the concentration of γ-aminobutyric acid (GABA) between the two groups, and to investigate the relationship between brain metabolites and autism symptom severity in the ASD group. We did find a significant negative correlation in the ASD group between Autism Spectrum Screening Questionnaire (ASSQ) and GABA+/Cr, which may imply that severity of symptoms in ASD is associated with differences in the level of GABA in the brain, supporting the excitatory/inhibitory (E/I) imbalance theory. However we did not find a significant difference between the two groups in GABA levels.
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Affiliation(s)
- Maiken K. Brix
- Department of Radiology, Haukeland University HospitalBergen, Norway
- Department of Clinical Medicine (K1), University of BergenBergen, Norway
| | - Lars Ersland
- Department of Clinical Engineering, Haukeland University HospitalBergen, Norway
- NORMENT – KG Jebsen Center for Mental Disorders Research, University of BergenBergen, Norway
| | - Kenneth Hugdahl
- Department of Radiology, Haukeland University HospitalBergen, Norway
- NORMENT – KG Jebsen Center for Mental Disorders Research, University of BergenBergen, Norway
- Department of Biological and Medical Psychology, University of BergenBergen, Norway
- Division of Psychiatry, Haukeland University HospitalBergen, Norway
| | - Renate Grüner
- Department of Radiology, Haukeland University HospitalBergen, Norway
- NORMENT – KG Jebsen Center for Mental Disorders Research, University of BergenBergen, Norway
- Department of Physics and Technology, University of BergenBergen, Norway
| | - Maj-Britt Posserud
- Department of Child and Adolescent Psychiatry, Haukeland University HospitalBergen, Norway
| | - Åsa Hammar
- Department of Biological and Medical Psychology, University of BergenBergen, Norway
| | - Alexander R. Craven
- NORMENT – KG Jebsen Center for Mental Disorders Research, University of BergenBergen, Norway
- Department of Biological and Medical Psychology, University of BergenBergen, Norway
| | - Ralph Noeske
- MR Applications and Workflow Development, GE HealthcareBerlin, Germany
| | - C. John Evans
- CUBRIC, School of Psychology/Ysgol Seicoleg, Cardiff University/Prifysgol Caerdydd WalesCardiff, UK
| | - Hanne B. Walker
- Faculty of Mathematics and Natural Sciences, University of OsloOslo, Norway
| | - Tore Midtvedt
- Department of Microbiology, Tumor and Cell Biology, Karolinska InstituteStockholm, Sweden
| | - Mona K. Beyer
- Department of Radiology and Nuclear Medicine, Oslo University HospitalOslo, Norway
- Faculty of Health Sciences, Department of Life Sciences and Health, Oslo and Akershus University College of Applied SciencesOslo, Norway
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21
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Berthet C, Xin L, Buscemi L, Benakis C, Gruetter R, Hirt L, Lei H. Non-invasive diagnostic biomarkers for estimating the onset time of permanent cerebral ischemia. J Cereb Blood Flow Metab 2014; 34:1848-55. [PMID: 25182663 PMCID: PMC4269763 DOI: 10.1038/jcbfm.2014.155] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 07/23/2014] [Accepted: 08/05/2014] [Indexed: 11/10/2022]
Abstract
The treatments for ischemic stroke can only be administered in a narrow time-window. However, the ischemia onset time is unknown in ~30% of stroke patients (wake-up strokes). The objective of this study was to determine whether MR spectra of ischemic brains might allow the precise estimation of cerebral ischemia onset time. We modeled ischemic stroke in male ICR-CD1 mice using a permanent middle cerebral artery filament occlusion model with laser Doppler control of the regional cerebral blood flow. Mice were then subjected to repeated MRS measurements of ipsilateral striatum at 14.1 T. A striking initial increase in γ-aminobutyric acid (GABA) and no increase in glutamine were observed. A steady decline was observed for taurine (Tau), N-acetyl-aspartate (NAA) and similarly for the sum of NAA+Tau+glutamate that mimicked an exponential function. The estimation of the time of onset of permanent ischemia within 6 hours in a blinded experiment with mice showed an accuracy of 33±10 minutes. A plot of GABA, Tau, and neuronal marker concentrations against the ratio of acetate/NAA allowed precise separation of mice whose ischemia onset lay within arbitrarily chosen time-windows. We conclude that (1)H-MRS has the potential to detect the clinically relevant time of onset of ischemic stroke.
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Affiliation(s)
- Carole Berthet
- Department of Clinical Neurosciences, Neurology Service, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Lijing Xin
- 1] Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland [2] Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Lara Buscemi
- Department of Clinical Neurosciences, Neurology Service, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Corinne Benakis
- Department of Clinical Neurosciences, Neurology Service, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Rolf Gruetter
- 1] Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland [2] Department of Radiology, University of Geneva, Geneva, Switzerland [3] Department of Radiology, University of Lausanne, Lausanne, Switzerland [4] AIT, Center for Biomedical Imaging (CIBM), Institute of the Physics of Biological Systems, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Lorenz Hirt
- Department of Clinical Neurosciences, Neurology Service, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Hongxia Lei
- 1] Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Lausanne, Switzerland [2] Department of Radiology, University of Lausanne, Lausanne, Switzerland
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Wang J, Du H, Ma X, Pittman B, Castracane L, Li TK, Behar KL, Mason GF. Metabolic products of [2-(13) C]ethanol in the rat brain after chronic ethanol exposure. J Neurochem 2013; 127:353-64. [PMID: 24033360 PMCID: PMC6145094 DOI: 10.1111/jnc.12405] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 08/04/2013] [Accepted: 08/06/2013] [Indexed: 01/05/2023]
Abstract
Most ingested ethanol is metabolized in the liver to acetaldehyde and then to acetate, which can be oxidized by the brain. This project assessed whether chronic exposure to alcohol can increase cerebral oxidation of acetate. Through metabolism, acetate may contribute to long-term adaptation to drinking. Two groups of adult male Sprague-Dawley rats were studied, one treated with ethanol vapor and the other given room air. After 3 weeks the rats received an intravenous infusion of [2-(13) C]ethanol via a lateral tail vein for 2 h. As the liver converts ethanol to [2-(13) C]acetate, some of the acetate enters the brain. Through oxidation the (13) C is incorporated into the metabolic intermediate α-ketoglutarate, which is converted to glutamate (Glu), glutamine (Gln), and GABA. These were observed by magnetic resonance spectroscopy and found to be (13) C-labeled primarily through the consumption of ethanol-derived acetate. Brain Gln, Glu, and, GABA (13) C enrichments, normalized to (13) C-acetate enrichments in the plasma, were higher in the chronically treated rats than in the ethanol-naïve rats, suggesting increased cerebral uptake and oxidation of circulating acetate. Chronic ethanol exposure increased incorporation of systemically derived acetate into brain Gln, Glu, and GABA, key neurochemicals linked to brain energy metabolism and neurotransmission. The liver converts ethanol to acetate, which may contribute to long-term adaptation to drinking. Astroglia oxidize acetate and generate neurochemicals, while neurons and glia may also oxidize ethanol. When (13) C-ethanol is administered intravenously, (13) C-glutamine, glutamate, and GABA, normalized to (13) C-acetate, were higher in chronic ethanol-exposed rats than in control rats, suggesting that ethanol exposure increases cerebral oxidation of circulating acetate.
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Affiliation(s)
- Jie Wang
- Wuhan Institute of Physics and Mathematics, Chinese Academy of Science, Wuhan, Hubei, China, 430071
- Department of Diagnostic Radiology
| | - Hongying Du
- Department of Diagnostic Radiology
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, P. R.China, 430070
| | | | - Brian Pittman
- Department of Psychiatry, School of Medicine, Yale University, New Haven, Connecticut, USA, 06511
| | | | - Ting-Kai Li
- Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA, 27710
| | - Kevin L. Behar
- Department of Psychiatry, School of Medicine, Yale University, New Haven, Connecticut, USA, 06511
| | - Graeme F. Mason
- Department of Diagnostic Radiology
- Department of Psychiatry, School of Medicine, Yale University, New Haven, Connecticut, USA, 06511
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Rojas DC, Singel D, Steinmetz S, Hepburn S, Brown MS. Decreased left perisylvian GABA concentration in children with autism and unaffected siblings. Neuroimage 2013; 86:28-34. [PMID: 23370056 DOI: 10.1016/j.neuroimage.2013.01.045] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 11/29/2012] [Accepted: 01/14/2013] [Indexed: 12/27/2022] Open
Abstract
Imbalanced levels of excitation and inhibition (E/I) have been proposed to account for various behavioral and electrophysiological phenotypes in autism. Although proton magnetic resonance spectroscopy ((1)H-MRS) studies have been published on various metabolite levels in autism, including glutamate, the major excitatory neurotransmitter, few (1)H-MRS studies have yet been conducted the major inhibitory neurotransmitter GABA. Seventeen individuals with autism spectrum disorders (ASD) participated in a single-voxel, point resolved spectroscopy (PRESS) study conducted on a 3T magnet. Data were also acquired on 14 unaffected siblings of children with autism, and 17 age- and gender-matched healthy control subjects. GABA concentration was measured along with Creatine (Cr) in a single voxel aligned with the auditory cortex in the perisylvian region of the left hemisphere. The ratio of GABA to Cr was significantly lower in the ASD group than the control subjects. Siblings also exhibited lower GABA/Cr ratios compared to controls. Cr concentration did not differ between groups. The volumes of gray matter, white matter and CSF did not differ between groups in the whole brain or within the spectroscopy voxel. Reduced auditory GABA concentration in ASD is consistent with one previous MRS study of GABA concentration in the frontal lobe in autism, suggesting that multiple neocortical areas may be involved. Lower GABA levels are consistent with theories of ASD as a disorder involving impaired inhibitory neurotransmission and E/I imbalance. The reduction in unaffected siblings suggests that it may be a heritable biomarker, or endophenotype, of autism.
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Affiliation(s)
- Donald C Rojas
- Department of Psychiatry, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA; Colorado Translational Research Imaging Center, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA.
| | - Debra Singel
- Department of Radiology, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA; Colorado Translational Research Imaging Center, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA
| | - Sarah Steinmetz
- Department of Psychiatry, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA
| | - Susan Hepburn
- Department of Psychiatry, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA; JFK Partners, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA
| | - Mark S Brown
- Department of Radiology, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA; Colorado Translational Research Imaging Center, University of Colorado Denver Anschutz Medical Campus, 13001 E. 17th Avenue, Aurora, CO 80045, USA
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24
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Hackett MJ, Lee J, El-Assaad F, McQuillan JA, Carter EA, Grau GE, Hunt NH, Lay PA. FTIR imaging of brain tissue reveals crystalline creatine deposits are an ex vivo marker of localized ischemia during murine cerebral malaria: general implications for disease neurochemistry. ACS Chem Neurosci 2012; 3:1017-24. [PMID: 23259037 DOI: 10.1021/cn300093g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 09/11/2012] [Indexed: 12/13/2022] Open
Abstract
Phosphocreatine is a major cellular source of high energy phosphates, which is crucial to maintain cell viability under conditions of impaired metabolic states, such as decreased oxygen and energy availability (i.e., ischemia). Many methods exist for the bulk analysis of phosphocreatine and its dephosphorylated product creatine; however, no method exists to image the distribution of creatine or phosphocreatine at the cellular level. In this study, Fourier transform infrared (FTIR) spectroscopic imaging has revealed the ex vivo development of creatine microdeposits in situ in the brain region most affected by the disease, the cerebellum of cerebral malaria (CM) diseased mice; however, such deposits were also observed at significantly lower levels in the brains of control mice and mice with severe malaria. In addition, the number of deposits was observed to increase in a time-dependent manner during dehydration post tissue cutting. This challenges the hypotheses in recent reports of FTIR spectroscopic imaging where creatine microdeposits found in situ within thin sections from epileptic, Alzheimer's (AD), and amlyoid lateral sclerosis (ALS) diseased brains were proposed to be disease specific markers and/or postulated to contribute to the brain pathogenesis. As such, a detailed investigation was undertaken, which has established that the creatine microdeposits exist as the highly soluble HCl salt or zwitterion and are an ex-vivo tissue processing artifact and, hence, have no effect on disease pathogenesis. They occur as a result of creatine crystallization during dehydration (i.e., air-drying) of thin sections of brain tissue. As ischemia and decreased aerobic (oxidative metabolism) are common to many brain disorders, regions of elevated creatine-to-phosphocreatine ratio are likely to promote crystal formation during tissue dehydration (due to the lower water solubility of creatine relative to phosphocreatine). The results of this study have demonstrated that although the deposits do not occur in vivo, and do not directly play any role in disease pathogenesis, increased levels of creatine deposits within air-dried tissue sections serve as a highly valuable marker for the identification of tissue regions with an altered metabolic status. In this study, the location of crystalline creatine deposits were used to identify whether an altered metabolic state exists within the molecular and granular layers of the cerebellum during CM, which complements the recent discovery of decreased oxygen availability in the brain during this disease.
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Affiliation(s)
- Mark J. Hackett
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | - Joonsup Lee
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | | | | | | | | | | | - Peter A. Lay
- School of Chemistry, The University of Sydney, NSW 2006, Australia
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25
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Mullins PG, McGonigle DJ, O'Gorman RL, Puts NAJ, Vidyasagar R, Evans CJ, Edden RAE. Current practice in the use of MEGA-PRESS spectroscopy for the detection of GABA. Neuroimage 2012; 86:43-52. [PMID: 23246994 DOI: 10.1016/j.neuroimage.2012.12.004] [Citation(s) in RCA: 394] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 09/11/2012] [Accepted: 12/03/2012] [Indexed: 10/27/2022] Open
Abstract
There is increasing interest in the use of edited proton magnetic resonance spectroscopy for the detection of GABA in the human brain. At a recent meeting held at Cardiff University, a number of spectroscopy groups met to discuss the acquisition, analysis and interpretation of GABA-edited MR spectra. This paper aims to set out the issues discussed at this meeting, reporting areas of consensus around parameters and procedures in the field and highlighting those areas where differences remain. It is hoped that this paper can fulfill two needs, providing a summary of the current 'state-of-the-art' in the field of GABA-edited MRS at 3T using MEGA-PRESS and a basic guide to help researchers new to the field to avoid some of the pitfalls inherent in the acquisition and processing of edited MRS for GABA.
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Affiliation(s)
- Paul G Mullins
- Bangor Imaging Unit, School of Psychology, Bangor University, Bangor, LL57 2AS, UK.
| | - David J McGonigle
- CUBRIC, School of Psychology, Cardiff University, Cardiff, CF10 3AT, UK; School of Biosciences, Cardiff University, Cardiff, CF10 3AT, UK
| | - Ruth L O'Gorman
- University Children's Hospital, Steinwiesstrasse 75, 8032 Zürich, Switzerland; Center for Integrative Human Physiology (ZIHP), University of Zürich, Switzerland
| | - Nicolaas A J Puts
- Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA; F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, 707 North Broadway Street, Room G-25, Baltimore, MD 21205, USA
| | - Rishma Vidyasagar
- Biomedical Imaging Institute, School of Cancer and Enabling Sciences, Manchester University, Stopford Building, Oxford Road, Manchester, M13 9PL, UK
| | - C John Evans
- CUBRIC, School of Psychology, Cardiff University, Cardiff, CF10 3AT, UK
| | | | - Richard A E Edden
- Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA; F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, 707 North Broadway Street, Room G-25, Baltimore, MD 21205, USA
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Hong ST, Balla DZ, Choi C, Pohmann R. Rat strain-dependent variations in brain metabolites detected by in vivo (1) H NMR spectroscopy at 16.4T. NMR IN BIOMEDICINE 2011; 24:1401-1407. [PMID: 21465594 DOI: 10.1002/nbm.1703] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 01/24/2011] [Accepted: 02/09/2011] [Indexed: 05/30/2023]
Abstract
Localized in vivo (1) H NMR spectroscopy is playing an increasing role in preclinical studies, because of its ability to quantify the concentrations of up to 20 metabolites in rat brain. To assess the differences between often-used rat strains, the neurochemical profiles of Sprague-Dawley, Wistar and Fischer rats were determined at ultrashort TE at 16.4 T. To ascertain high-qualitative quantification, a first experiment examined the dependence of the measuring time on the quantification results and precision by precisely the number of averages between 16 and 320. It was shown that most metabolites can be quantified accurately within a short scan time, yielding Cramér-Rao lower bounds below 20% and stable concentrations for 16 metabolites with as few as 32 or 64 averages in the thalamus and hippocampus, respectively. Interstrain differences in metabolite concentrations were shown to be moderate, with taurine varying significantly between Sprague-Dawley and Wistar rats, and slightly more distinct differences from Fischer rats, including variations in glutamate and myo-inositol. The high spectral quality and quantification precision of all data again demonstrated the potential of in vivo (1)H NMR spectroscopy at ultrahigh field.
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Affiliation(s)
- Sung-Tak Hong
- High-Field Magnetic Resonance Center, Max-Planck Institute for Biological Cybernetics, Spemannstrasse 41, Tübingen, Germany
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27
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Detour J, Elbayed K, Piotto M, Moussallieh F, Nehlig A, Namer I. Ultra fast in vivo microwave irradiation for enhanced metabolic stability of brain biopsy samples during HRMAS NMR analysis. J Neurosci Methods 2011; 201:89-97. [DOI: 10.1016/j.jneumeth.2011.07.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 07/11/2011] [Accepted: 07/14/2011] [Indexed: 11/26/2022]
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28
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Fujimoto S, Morikawa S, Inubushi T. An MR comparison study of cardiogenic and noncardiogenic pulmonary edema in animal models. J Magn Reson Imaging 2011; 34:1092-8. [DOI: 10.1002/jmri.22730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 06/28/2011] [Indexed: 11/10/2022] Open
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Non-invasive evaluation of the GABAergic/glutamatergic system in autistic patients observed by MEGA-editing proton MR spectroscopy using a clinical 3 tesla instrument. J Autism Dev Disord 2011; 41:447-54. [PMID: 20652388 DOI: 10.1007/s10803-010-1065-0] [Citation(s) in RCA: 166] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Amino acids related to neurotransmitters and the GABAergic/glutamatergic system were measured using a 3 T-MRI instrument in 12 patients with autism and 10 normal controls. All measurements were performed in the frontal lobe (FL) and lenticular nuclei (LN) using a conventional sequence for n-acetyl aspartate (NAA) and glutamate (Glu), and the MEGA-editing method for GABA. The GABA level and [GABA]/[NAA] ratio were significantly lower (p < 0.01) in the FL, but not the LN, in patients with autism compared to normal controls. The [GABA]/[Glu] ratio in the FL was also significantly lower (p < 0.05) in the patients than in the normal controls, thus suggesting a possible abnormality in the regulation between GABA and Glu.
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30
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Harada M, Kubo H, Nose A, Nishitani H, Matsuda T. Measurement of variation in the human cerebral GABA level by in vivo MEGA-editing proton MR spectroscopy using a clinical 3 T instrument and its dependence on brain region and the female menstrual cycle. Hum Brain Mapp 2011; 32:828-33. [PMID: 20645307 DOI: 10.1002/hbm.21086] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The objectives of this study were to examine the reproducibility of the MEGA-editing J-difference technique and to determine the normal variation in the γ-aminobutyric acid (GABA) level depending on the cerebral region and its fluctuation according to the menstrual cycle as baseline data for clinical application. The participants consisted of 15 normal adult volunteers (eight men and seven women), and all measurements were repeated twice in all participants. The MEGA-editing pulses were incorporated into point-resolved spectroscopy on a 3 T instrument to obtain the J-difference editing spectra from a voxel located in the lentiform nuclei (LN), left frontal lobe (FL), and anterior cingulate cortex (AC). The GABA levels in the gray matter (GM) were compensated by the fraction ratios of the gray and white matters and cerebrospinal fluid in the measurement volume. The extent of the variation in GABA was almost the same as that observed in the major metabolites, and its reproducibility was also maintained (intraclass correlation coefficient > 0.7). GABA level was highest in LN and lowest in AC. A difference in the GABA level between the follicular and luteal phases of the menstrual cycle was found in both LN and FL, but not in AC. This technique showed the differences in the GABA levels in the GM and the region-specific decrease in the GABA levels during the women's luteal phase.
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Affiliation(s)
- Masafumi Harada
- Department of Medical Imaging, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, Japan.
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Abstract
Human evolution is characterized by the rapid expansion of brain size and drastic increase in cognitive capabilities. It has long been suggested that these changes were accompanied by modifications of brain metabolism. Indeed, human-specific changes on gene expression or amino acid sequence were reported for a number of metabolic genes, but actual metabolite measurements in humans and apes have remained scarce. Here, we investigate concentrations of more than 100 metabolites in the prefrontal and cerebellar cortex in 49 humans, 11 chimpanzees, and 45 rhesus macaques of different ages using gas chromatography-mass spectrometry (GC-MS). We show that the brain metabolome undergoes substantial changes, both ontogenetically and evolutionarily: 88% of detected metabolites show significant concentration changes with age, whereas 77% of these metabolic changes differ significantly among species. Although overall metabolic divergence reflects phylogenetic relationships among species, we found a fourfold acceleration of metabolic changes in prefrontal cortex compared with cerebellum in the human lineage. These human-specific metabolic changes are paralleled by changes in expression patterns of the corresponding enzymes, and affect pathways involved in synaptic transmission, memory, and learning.
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32
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Muthukumaraswamy SD, Evans CJ, Edden RAE, Wise RG, Singh KD. Individual variability in the shape and amplitude of the BOLD-HRF correlates with endogenous GABAergic inhibition. Hum Brain Mapp 2011; 33:455-65. [PMID: 21416560 DOI: 10.1002/hbm.21223] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 10/27/2010] [Accepted: 11/11/2010] [Indexed: 11/11/2022] Open
Abstract
It has previously been demonstrated that there is a negative correlation between the amplitude of the BOLD response and resting γ amino-butyric acid (GABA) concentration in visual cortex. The work here is the first to empirically characterize individual variability in the haemodynamic response functions (HRFs) in response to a simple visual stimulus and baseline GABA concentration in a population of young adult males (n = 15, aged 20-28 years). The results demonstrate that GABA concentration is negatively correlated with BOLD response amplitude (r = -0.64, P < 0.02) and positively correlated with HRF width (r = 0.67, P < 0.002), that is, individuals with higher resting GABA concentration tend to exhibit smaller and wider HRFs. No correlations were observed with resting cerebral blood flow and GABA concentration and similarly, no correlations were observed between GABA and the proportional tissue content of the MRS voxel. We argue that correlation of the height of the HRF is supportive of the view that the previously observed correlations between BOLD amplitudes and GABA are reflective of differences in neuronal activity. However, the changes in HRF shape in individuals with higher baseline GABA levels are suggestive that differing vascular response characteristics may also make a significant contribution. Our results reinforce the view that variability in endogenous factors, such as neurotransmitter concentration, can have a profound effect on the vascular haemodynamic response. This has important implications for between-cohort fMRI studies in which variation in parameters such as GABA concentration may lead to group differences in the BOLD signal.
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Faria A, Macedo Jr. F, Marsaioli A, Ferreira M, Cendes F. Classification of brain tumor extracts by high resolution ¹H MRS using partial least squares discriminant analysis. Braz J Med Biol Res 2011; 44:149-64. [DOI: 10.1590/s0100-879x2010007500146] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2009] [Accepted: 11/17/2010] [Indexed: 11/22/2022] Open
Affiliation(s)
- A.V. Faria
- Universidade Estadual de Campinas; The Johns Hopkins University, USA
| | - F.C. Macedo Jr.
- Universidade Estadual de Campinas, Brasil; Universidade Estadual de Londrina, Brasil
| | | | | | - F. Cendes
- Universidade Estadual de Campinas, Brasil
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Steen C, Wilczak N, Hoogduin JM, Koch M, De Keyser J. Reduced creatine kinase B activity in multiple sclerosis normal appearing white matter. PLoS One 2010; 5:e10811. [PMID: 20520825 PMCID: PMC2876025 DOI: 10.1371/journal.pone.0010811] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Accepted: 05/05/2010] [Indexed: 11/26/2022] Open
Abstract
Background Two studies using 31P-magnetic resonance spectroscopy (MRS) reported enhanced phosphocreatine (PCr) levels in normal appearing white matter (NAWM) of subjects with multiple sclerosis (MS), but this finding could not be properly explained. Methodology/Principal Findings We performed 31P-MRS and 1H-MRS in the NAWM in 36 subjects, including 17 with progressive MS, 9 with benign MS, and 10 healthy controls. Compared to controls, PCr/β-ATP and PCr/total 31P ratios were significantly increased in subjects with progressive MS, but not with benign MS. There was no correlation between PCr ratios and the N-acetylaspartate/creatine ratio, suggesting that elevated PCr levels in NAWM were not secondary to axonal loss. In the central nervous system, PCr is degraded by creatine kinase B (CK-B), which in the white matter is confined to astrocytes. In homogenates of NAWM from 10 subjects with progressive MS and 10 controls without central nervous system disease, we measured CK-B levels with an ELISA, and measured its activity with an enzymatic assay kit. Compared to controls, both CK-B levels and activity were decreased in subjects with MS (22.41 versus 46.28 µg/ml; p = 0.0007, and 2.89 versus 7.76 U/l; p<0.0001). Conclusions/Significance Our results suggest that PCr metabolism in the NAWM in MS is impaired due to decreased CK-B levels. Our findings raise the possibility that a defective PCr metabolism in astrocytes might contribute to the degeneration of oligodendrocytes and axons in MS.
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Affiliation(s)
- Christel Steen
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Nadine Wilczak
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Johannes M. Hoogduin
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
- BCN-Neuroimaging Center, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Marcus Koch
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jacques De Keyser
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Department of Neurology, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
- * E-mail:
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Macri MA, D'Alessandro N, Di Giulio C, Di Iorio P, Di Luzio S, Giuliani P, Esposito E, Pokorski M. Region-specific effects on brain metabolites of hypoxia and hyperoxia overlaid on cerebral ischemia in young and old rats: a quantitative proton magnetic resonance spectroscopy study. J Biomed Sci 2010; 17:14. [PMID: 20178616 PMCID: PMC2838762 DOI: 10.1186/1423-0127-17-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Accepted: 02/23/2010] [Indexed: 11/18/2022] Open
Abstract
Background Both hypoxia and hyperoxia, deregulating the oxidative balance, may play a role in the pathology of neurodegenerative disorders underlain by cerebral ischemia. In the present study, quantitative proton magnetic resonance spectroscopy was used to evaluate regional metabolic alterations, following a 24-hour hypoxic or hyperoxic exposure on the background of ischemic brain insult, in two contrasting age-groups of rats: young - 3 months old and aged - 24 months old. Methods Cerebral ischemia was induced by ligation of the right common carotid artery. Concentrations of eight metabolites (alanine, choline-containing compounds, total creatine, γ-aminobutyric acid, glutamate, lactate, myo-inositol and N-acetylaspartate) were quantified from extracts in three different brain regions (fronto-parietal and occipital cortices and the hippocampus) from both hemispheres. Results In the control normoxic condition, there were significant increases in lactate and myo-inositol concentrations in the hippocampus of the aged rats, compared with the respective values in the young ones. In the ischemia-hypoxia condition, the most prevalent changes in the brain metabolites were found in the hippocampal regions of both young and aged rats; but the effects were more evident in the aged animals. The ischemia-hyperoxia procedure caused less dedicated changes in the brain metabolites, which may reflect more limited tissue damage. Conclusions We conclude that the hippocampus turns out to be particularly susceptible to hypoxia overlaid on cerebral ischemia and that old age further increases this susceptibility.
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Affiliation(s)
- Maria A Macri
- Department of Respiratory Research, Medical Research Center, Polish Academy of Sciences, Warsaw, Poland
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Opstad KS, Wright AJ, Bell BA, Griffiths JR, Howe FA. Correlations between in vivo (1)H MRS and ex vivo (1)H HRMAS metabolite measurements in adult human gliomas. J Magn Reson Imaging 2010; 31:289-97. [PMID: 20099340 DOI: 10.1002/jmri.22039] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To assess how accurately ex vivo high-resolution magic angle spinning (HRMAS) proton magnetic resonance spectroscopy ((1)H MRS) from small biopsy tissues relate to in vivo (1)H MRS (from larger tumor volumes) in human astrocytomas. MATERIALS AND METHODS In vivo (PRESS, TE = 30 msec) and ex vivo (presaturation) (1)H spectra of 17 human astrocytomas (4 grade II, 1 grade III and 12 glioblastomas) were quantified using LCModel. Concentrations of 11 metabolites and 2 lipid/macromolecules were retrospectively compared, with histogram analysis of the in vivo MRI data used to evaluate tumor heterogeneity. RESULTS For homogeneous-appearing tumors, significant correlations were found between in vivo and ex vivo (1)H MRS concentrations of those metabolites known to be metabolically stable in postmortem tissues (eg, creatine, myo-inositol, total cholines, and the approximately 1.3 and 0.9 ppm lipids). Anaerobic glycolysis during biopsy surgical removal depletes the tissue of glucose, increasing alanine and lactate, and resulted in no correlation between these in vivo and ex vivo metabolite concentrations. CONCLUSION Within defined limitations, ex vivo astrocytoma biopsy HRMAS (1)H spectra have similar metabolic profiles to that obtained in vivo and therefore detailed ex vivo characterization of glioma biopsies can directly relate to the original tumor.
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Affiliation(s)
- Kirstie S Opstad
- Division of Cardiac and Vascular Sciences, St George's, University of London, London, UK.
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Taki MM, Harada M, Mori K, Kubo H, Nose A, Matsuda T, Nishitani H. High gamma-aminobutyric acid level in cortical tubers in epileptic infants with tuberous sclerosis complex measured with the MEGA-editing J-difference method and a three-Tesla clinical MRI Instrument. Neuroimage 2009; 47:1207-14. [PMID: 19481612 DOI: 10.1016/j.neuroimage.2009.05.060] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Revised: 04/27/2009] [Accepted: 05/19/2009] [Indexed: 01/07/2023] Open
Abstract
The purpose of this study was to estimate the gamma-aminobutyric acid (GABA) and glutamate plus glutamine (Glx) concentrations in the cortical tubers of patients with tuberous sclerosis complex (TSC) using the MEGA-editing J-difference method and a stimulated echo-acquisition mode with a short echo time, and to determine which abnormality was more dominant between GABA and Glx in patients with TSC with epilepsy. This study included six patients with TSC (mean age, 4.3 years) and seven control subjects (mean age, 4.8 years). Measurements were obtained with a three-Tesla apparatus and postprocessing was conducted with an LCModel. The GABA level in the cortical gray matter (cgGABA) was calculated as a result of segmentation in voxels and from the literature values for gray and white matter ratios for GABA. Increased GABA and myo-inositol (mI) concentrations and a decreased N-acetyl aspartate (NAA) concentration were observed in the cortical tubers. The cgGABA level, and cgGABA/NAA and cgGABA/Glx ratios were also higher in patients with TSC than in control subjects. No significant difference was found in Glx concentration between patients with TSC and control subjects. Although the number of patients with TSC in this study was small, the increase in GABA and no significant change in Glx were consistent with previous neurochemical studies and support the hypothesis that brain GABA plays a key role in the pathophysiology of epilepsy during the process of neuronal development.
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Affiliation(s)
- Masako Minato Taki
- Department of Radiology, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima 770-8503, Japan
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Opstad KS, Bell BA, Griffiths JR, Howe FA. An assessment of the effects of sample ischaemia and spinning time on the metabolic profile of brain tumour biopsy specimens as determined by high-resolution magic angle spinning (1)H NMR. NMR IN BIOMEDICINE 2008; 21:1138-47. [PMID: 18666093 DOI: 10.1002/nbm.1296] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
High-resolution magic angle spinning (HRMAS) (1)H NMR of biopsy tissue provides a biochemical profile that has potential diagnostic and prognostic value, and can aid interpretation of the lower-resolution (1)H-NMR spectra obtained in vivo. However, the biochemical profile obtained may be affected by experimental factors such as a period of ischaemia before snap-freezing of the biopsy tissue for subsequent analysis and the mechanical stress of the spinning procedure of HRMAS itself. We have used normal rat brain cortex as a 'gold standard', either funnel-frozen or deliberately allowed to become ischaemic for set periods of time before snap-freezing, to quantitatively investigate these two effects. In addition, we have compared biochemical changes that occur in normal rat brain during HRMAS (spun continuously at 5 kHz for 4 h at 4 degrees C as could be required for a two-dimensional acquisition) with those that occur in biopsy samples from low-grade and high-grade adult human astrocytomas, during the same HRMAS procedure. Significant changes due to delayed initial sample freezing were noted in metabolites associated with glycolysis (alanine, glucose and lactate), as expected. However, for the funnel-frozen rat tissue at 4 degrees C, there were even more significant changes, which appear to be the result of extended spinning at 5 kHz. In particular, the 18% total creatine increase observed is unlikely to be de novo synthesis of creatine. More likely, the asymptotic exponential increase in creatine suggests an exponential release of an NMR-invisible bound creatine store as a result of tissue damage from mechanical stress of sample spinning. Overall, it appears that tissue ischaemia during biopsy excision and delays in snap-freezing may have less significant effects on metabolite profile than the prolonged spinning times required for two-dimensional HRMAS, and this must be accounted for when results are being interpreted.
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Affiliation(s)
- Kirstie S Opstad
- Division of Basic Medical Sciences, St George's, University of London, UK.
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Hong ST, Choi CB, Park C, Hong KS, Cheong C, Jeon YW, Choe BY. Variation of the choline signal intensity in the dorsolateral prefrontal cortex of rats exposed to the forced swimming test as detected by in vivo 1H MR spectroscopy. J Neurosci Methods 2007; 165:89-94. [PMID: 17606300 DOI: 10.1016/j.jneumeth.2007.05.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2007] [Revised: 05/15/2007] [Accepted: 05/21/2007] [Indexed: 01/18/2023]
Abstract
BACKGROUND (1)H magnetic resonance spectroscopy (MRS) has documented an increased Cho/Cr ratio in the dorsolateral prefrontal cortex (DLPFC) in major depressive disorder (MDD). The aim of this study was to investigate neurochemical alterations in the left DLPFC, considered a main area of pathogenesis in depression, using rats exposed to the forced swimming test (FST). MATERIALS AND METHODS Twenty-four male rats were used for the MRI and in vivo(1)H MRS studies. Rats exposed to the FST to induce a depressed mental status. Using in vivo(1)H MRS, the metabolite ratios of the rats with a depressed mental status and the controls, were measured and the values of the two groups were compared. RESULTS The Cho/Cr and Cho/NAA ratios in the DLPFC of the rats with a depressed mental status were significantly higher than that in the controls. CONCLUSIONS The present study demonstrates a significantly increased Cho/Cr ratio in the DLPFC of rats with depression compared with controls. This result may suggest an accelerated turnover of membrane without neuronal loss is occurring in the DLPFC of the rats with depression.
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Affiliation(s)
- Sung-Tak Hong
- Department of Biomedical Engineering, College of Medicine, The Catholic University of Korea, #505 Banpo-Dong, Seocho-Gu, Seoul 137-040, Republic of Korea
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Moffett JR, Ross B, Arun P, Madhavarao CN, Namboodiri AMA. N-Acetylaspartate in the CNS: from neurodiagnostics to neurobiology. Prog Neurobiol 2007; 81:89-131. [PMID: 17275978 PMCID: PMC1919520 DOI: 10.1016/j.pneurobio.2006.12.003] [Citation(s) in RCA: 991] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 12/07/2006] [Accepted: 12/11/2006] [Indexed: 01/02/2023]
Abstract
The brain is unique among organs in many respects, including its mechanisms of lipid synthesis and energy production. The nervous system-specific metabolite N-acetylaspartate (NAA), which is synthesized from aspartate and acetyl-coenzyme A in neurons, appears to be a key link in these distinct biochemical features of CNS metabolism. During early postnatal central nervous system (CNS) development, the expression of lipogenic enzymes in oligodendrocytes, including the NAA-degrading enzyme aspartoacylase (ASPA), is increased along with increased NAA production in neurons. NAA is transported from neurons to the cytoplasm of oligodendrocytes, where ASPA cleaves the acetate moiety for use in fatty acid and steroid synthesis. The fatty acids and steroids produced then go on to be used as building blocks for myelin lipid synthesis. Mutations in the gene for ASPA result in the fatal leukodystrophy Canavan disease, for which there is currently no effective treatment. Once postnatal myelination is completed, NAA may continue to be involved in myelin lipid turnover in adults, but it also appears to adopt other roles, including a bioenergetic role in neuronal mitochondria. NAA and ATP metabolism appear to be linked indirectly, whereby acetylation of aspartate may facilitate its removal from neuronal mitochondria, thus favoring conversion of glutamate to alpha ketoglutarate which can enter the tricarboxylic acid cycle for energy production. In its role as a mechanism for enhancing mitochondrial energy production from glutamate, NAA is in a key position to act as a magnetic resonance spectroscopy marker for neuronal health, viability and number. Evidence suggests that NAA is a direct precursor for the enzymatic synthesis of the neuron specific dipeptide N-acetylaspartylglutamate, the most concentrated neuropeptide in the human brain. Other proposed roles for NAA include neuronal osmoregulation and axon-glial signaling. We propose that NAA may also be involved in brain nitrogen balance. Further research will be required to more fully understand the biochemical functions served by NAA in CNS development and activity, and additional functions are likely to be discovered.
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Affiliation(s)
- John R Moffett
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Building C, 4301 Jones Bridge Rd., Bethesda, MD 20814, USA.
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Ellegood J, McKay RT, Hanstock CC, Beaulieu C. Anisotropic diffusion of metabolites in peripheral nerve using diffusion weighted magnetic resonance spectroscopy at ultra-high field. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2007; 184:20-8. [PMID: 17027305 DOI: 10.1016/j.jmr.2006.09.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Revised: 08/25/2006] [Accepted: 09/15/2006] [Indexed: 05/12/2023]
Abstract
Although the diffusivity and anisotropy of water has been investigated thoroughly in ordered axonal systems (i.e., nervous tissue), there have been very few studies on the directional dependence of diffusion of metabolites. In this study, the mean apparent diffusion coefficient (Trace/3 ADC) and fractional anisotropy (FA) values of the intracellular metabolites N-acetyl aspartate (NAA), creatine and phosphocreatine (tCr), choline (Cho), taurine (Tau), and glutamate and glutamine (Glx) were measured parallel and perpendicular to the length of excised frog sciatic nerve using a water suppressed, diffusion-weighted, spin-echo pulse sequence at 18.8T. The degree of anisotropy (FA) of NAA (0.41+/-0.09) was determined to be less than tCr (0.59+/-0.07) and Cho (0.61+/-0.11), which is consistent with previously reported human studies of white matter. In contrast, Glx diffusion was found to be almost isotropic with an FA value of 0.20+/-0.06. The differences of FA between the metabolites is most likely due to their differing micro-environments and could be beneficial as an indicator of compartment specific changes with disease, information not readily available with water diffusion.
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Affiliation(s)
- Jacob Ellegood
- Department of Biomedical Engineering, University of Alberta, 1098 Research Transition Facility, Edmonton, Alta., Canada T6G 2V2
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42
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Philippossian G, Welti DH, Fumeaux R, Richli U, Anantharaman K. Synthesis and NMR characterization of (15N)taurine [2-(15N)aminoethanesulfonic acid]. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580271105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Jensen JE, Frederick BDB, Renshaw PF. Grey and white matter GABA level differences in the human brain using two-dimensional, J-resolved spectroscopic imaging. NMR IN BIOMEDICINE 2005; 18:570-6. [PMID: 16273508 DOI: 10.1002/nbm.994] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A novel, two-dimensional, J-resolved chemical-shift imaging sequence was used to collect gamma-aminobutyric acid (GABA) spectroscopic imaging data on six healthy subjects at 4 T. Using image segmentation and a linear-regression analysis relating brain GABA level to tissue-type, a consistent and significant (n = 6, p < 0.01) elevation of mean GABA levels was measured in the cortical grey matter (0.96 +/- 0.24 mm) compared with white matter (0.44 +/- 0.16 mm) across all six subjects. The results suggest an approximately two-fold elevation of GABA levels in cortical grey matter compared with white matter in vivo. Our findings are consistent with ex vivo studies in the literature of both animal and human brain and demonstrate the significant potential of this technique for detecting and quantifying tissue-specific neurochemical pathology in vivo.
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Affiliation(s)
- J Eric Jensen
- Brain Imaging Center, McLean Hospital, Belmont, MA 02478-9106, USA
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Scheurer E, Ith M, Dietrich D, Kreis R, Hüsler J, Dirnhofer R, Boesch C. Statistical evaluation of time-dependent metabolite concentrations: estimation of post-mortem intervals based on in situ 1H-MRS of the brain. NMR IN BIOMEDICINE 2005; 18:163-172. [PMID: 15578674 DOI: 10.1002/nbm.934] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Knowledge of the time interval from death (post-mortem interval, PMI) has an enormous legal, criminological and psychological impact. Aiming to find an objective method for the determination of PMIs in forensic medicine, 1H-MR spectroscopy (1H-MRS) was used in a sheep head model to follow changes in brain metabolite concentrations after death. Following the characterization of newly observed metabolites (Ith et al., Magn. Reson. Med. 2002; 5: 915-920), the full set of acquired spectra was analyzed statistically to provide a quantitative estimation of PMIs with their respective confidence limits. In a first step, analytical mathematical functions are proposed to describe the time courses of 10 metabolites in the decomposing brain up to 3 weeks post-mortem. Subsequently, the inverted functions are used to predict PMIs based on the measured metabolite concentrations. Individual PMIs calculated from five different metabolites are then pooled, being weighted by their inverse variances. The predicted PMIs from all individual examinations in the sheep model are compared with known true times. In addition, four human cases with forensically estimated PMIs are compared with predictions based on single in situ MRS measurements. Interpretation of the individual sheep examinations gave a good correlation up to 250 h post-mortem, demonstrating that the predicted PMIs are consistent with the data used to generate the model. Comparison of the estimated PMIs with the forensically determined PMIs in the four human cases shows an adequate correlation. Current PMI estimations based on forensic methods typically suffer from uncertainties in the order of days to weeks without mathematically defined confidence information. In turn, a single 1H-MRS measurement of brain tissue in situ results in PMIs with defined and favorable confidence intervals in the range of hours, thus offering a quantitative and objective method for the determination of PMIs.
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Affiliation(s)
- Eva Scheurer
- Institute of Forensic Medicine, University of Bern, Bern, Switzerland
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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.
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Affiliation(s)
- M A Macrì
- Dipartimento di Medicina Sperimentale e Patologia, Università La Sapienza di Roma, Roma, Italy.
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Iotti S, Frassineti C, Sabatini A, Vacca A, Barbiroli B. Quantitative mathematical expressions for accurate in vivo assessment of cytosolic [ADP] and DeltaG of ATP hydrolysis in the human brain and skeletal muscle. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2005; 1708:164-77. [PMID: 15953473 DOI: 10.1016/j.bbabio.2005.01.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2004] [Revised: 01/20/2005] [Accepted: 01/21/2005] [Indexed: 10/25/2022]
Abstract
Magnetic Resonance Spectroscopy affords the possibility of assessing in vivo the thermodynamic status of living tissues. The main thermodynamic variables relevant for the knowledge of the health of living tissues are: DeltaG of ATP hydrolysis and cytosolic [ADP], the latter as calculated from the apparent equilibrium constant of the creatine kinase reaction. In this study we assessed the stoichiometric equilibrium constant of the creatine kinase reaction by in vitro (31)P NMR measurements and computer calculations resulting to be: logK(CK)=8.00+/-0.07 at T=310 K and ionic strength I=0.25 M. This value refers to the equilibrium: PCr(2-)+ADP(3-)+ H(+)=Cr+ATP(4-). We also assessed by computer calculation the stoichiometric equilibrium constant of ATP hydrolysis obtaining the value: logK(ATP-hyd)=-12.45 at T=310 K and ionic strength I=0.25 M, which refers to the equilibrium: ATP(4-)+H(2)O=ADP(3-)+PO(4)(3-)+2H(+). Finally, we formulated novel quantitative mathematical expressions of DeltaG of ATP hydrolysis and of the apparent equilibrium constant of the creatine kinase reaction as a function of total [PCr], pH and pMg, all quantities measurable by in vivo (31)P MRS. Our novel mathematical expressions allow the in vivo assessment of cytosolic [ADP] and DeltaG of ATP hydrolysis in the human brain and skeletal muscle taking into account pH and pMg changes occurring in living tissues both in physiological and pathological conditions.
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Affiliation(s)
- Stefano Iotti
- Biochimica Clinica, Dipartimento di Medicina Clinica e Biotecnologia Applicata "D. Campanacci", Università di Bologna, Via Massarenti, 9, 40138 Bologna, Italy.
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Abstract
The putative anxiolytic activity of succinic acid was examined in male mice by using a number of experimental paradigms of anxiety and compared with that of the known anxiolytic compound diazepam. Use of the elevated plus-maze test revealed that diazepam (1.0, 2.0 and 4.0 mg/kg, PO) or succinic acid (3.0 or 6.0 mg/kg, PO) increased the percentage of entries into open arms and of time spent on open arms. In novel food consumption test, succinic acid (3.0, 6.0, and 12.0 mg/kg, IP) caused significant increases in food intake during 5 min when compared with the vehicle. In the stress-induced hyperthermia test, 40 min after drug administration rectal temperature was measured, succinic acid at dose of 1.5 mg/kg, inhibited stress-induced hyperthermia. Thus, these findings indicated that, in contrast with diazepam, succinic acid exhibits anxiolytic-like effect.
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Affiliation(s)
- Si Wei Chen
- Department of Pharmacology, Shenyang Pharmaceutical University, Box 41, 103 Wenhua Road, 110016 Shenyang, PR China.
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Mathew SJ, Shungu DC, Mao X, Smith ELP, Perera GM, Kegeles LS, Perera T, Lisanby SH, Rosenblum LA, Gorman JM, Coplan JD. A magnetic resonance spectroscopic imaging study of adult nonhuman primates exposed to early-life stressors. Biol Psychiatry 2003; 54:727-35. [PMID: 14512213 DOI: 10.1016/s0006-3223(03)00004-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND Long-term behavioral, immunologic, and neurochemical alterations have been found in primates exposed to adverse early rearing. METHODS Bonnet macaque (Macaca radiata) mother-infant dyads were exposed to uncertain requirements for food procurement (variable foraging demand, VFD) for a few months. Ten years later, these offspring and age- and gender-matched control subjects were studied using proton magnetic resonance spectroscopic imaging (MRSI). RESULTS In anterior cingulate, VFD-reared subjects displayed significantly decreased N-acetylaspartate (NAA) resonance and significantly increased glutamate-glutamine-gamma-aminobutyric acid (Glx) resonance relative to the stable neurometabolite creatine (Cr). Across all subjects, NAA/Cr and Glx/Cr ratios in the anterior cingulate were negatively correlated (r = -.638, p =.014). In the medial temporal lobe, the ratio of choline-containing compounds to Cr was significantly increased in VFD subjects. CONCLUSIONS These findings indicate that adverse early rearing in primates has an enduring impact on adult MRSI measures considered reflective of neuronal integrity and metabolism, membrane structure and glial function, and cerebral glutamate content, and that these alterations occur in the same brain regions implicated in trauma-related psychiatric disorders.
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Affiliation(s)
- Sanjay J Mathew
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York, USA
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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.
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Affiliation(s)
- Attila Schwarcz
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany
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Ith M, Bigler P, Scheurer E, Kreis R, Hofmann L, Dirnhofer R, Boesch C. Observation and identification of metabolites emerging during postmortem decomposition of brain tissue by means of in situ 1H-magnetic resonance spectroscopy. Magn Reson Med 2002; 48:915-20. [PMID: 12418008 DOI: 10.1002/mrm.10294] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Postmortem decomposition of brain tissue was investigated by (1)H-magnetic resonance spectroscopy (MRS) in a sheep head model and selected human cases. Aiming at the eventual estimation of postmortem intervals in forensic medicine, this study focuses on the characterization and identification of newly observed metabolites. In situ single-voxel (1)H-MRS at 1.5 T was complemented by multidimensional homo- and heteronuclear high-resolution NMR spectroscopy of an extract of sheep brain tissue. The inclusion of spectra of model solutions in the program LC Model confirmed the assignments in situ. The first postmortem phase was characterized mainly by changes in the concentrations of metabolites usually observed in vivo and by the appearance of previously reported decay products. About 3 days postmortem, new metabolites, including free trimethylammonium, propionate, butyrate, and iso-butyrate, started to appear in situ. Since the observed metabolites and the time course is comparable in sheep and human brain tissue, the model system seems to be appropriate.
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Affiliation(s)
- Michael Ith
- Department of Clinical Research (MR Spectroscopy and Methodology), University Bern, Switzerland
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