1
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Bhat UA, Kumar SA, Chakravarty S, Patel AB, Kumar A. Differential Effects of Chronic Ethanol Use on Mouse Neuronal and Astroglial Metabolic Activity. Neurochem Res 2023:10.1007/s11064-023-03922-y. [PMID: 37069415 DOI: 10.1007/s11064-023-03922-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/20/2023] [Accepted: 03/24/2023] [Indexed: 04/19/2023]
Abstract
Chronic alcohol use disorder, a major risk factor for the development of neuropsychiatric disorders including addiction to other substances, is associated with several neuropathology including perturbed neuronal and glial activities in the brain. It affects carbon metabolism in specific brain regions, and perturbs neuro-metabolite homeostasis in neuronal and glial cells. Alcohol induced changes in the brain neurochemical profile accompany the negative emotional state associated with dysregulated reward and sensitized stress response to withdrawal. However, the underlying alterations in neuro-astroglial activities and neurochemical dysregulations in brain regions after chronic alcohol use are poorly understood. This study evaluates the impact of chronic ethanol use on the regional neuro-astroglial metabolic activity using 1H-[13C]-NMR spectroscopy in conjunction with infusion of [1,6-13C2]glucose and sodium [2-13C]acetate, respectively, after 48 h of abstinence. Besides establishing detailed 13C labeling of neuro-metabolites in a brain region-specific manner, our results show chronic ethanol induced-cognitive deficits along with a reduction in total glucose oxidation rates in the hippocampus and striatum. Furthermore, using [2-13C]acetate infusion, we showed an alcohol-induced increase in astroglial metabolic activity in the hippocampus and prefrontal cortex. Interestingly, increased astroglia activity in the hippocampus and prefrontal cortex was associated with a differential expression of monocarboxylic acid transporters that are regulating acetate uptake and metabolism in the brain.
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Affiliation(s)
- Unis Ahmad Bhat
- Epigenetics and Neuropsychiatric Disorders Laboratory, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India
| | - Sreemantula Arun Kumar
- Applied Biology, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, India
| | - Sumana Chakravarty
- Applied Biology, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Anant Bahadur Patel
- Epigenetics and Neuropsychiatric Disorders Laboratory, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India.
| | - Arvind Kumar
- Epigenetics and Neuropsychiatric Disorders Laboratory, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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2
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Miller CO, Gantert LT, Previs SF, Chen Y, Anderson KD, Thomas JM, Sanacora G, Uslaner JM, Rothman DL, Mason GF. A Novel Biomarker of Neuronal Glutamate Metabolism in Nonhuman Primates Using Localized 1H-Magnetic Resonance Spectroscopy: Development and Effects of BNC375, an α7 Nicotinic Acetylcholine Receptor Positive Allosteric Modulator. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2022; 7:598-606. [PMID: 33309567 PMCID: PMC8005500 DOI: 10.1016/j.bpsc.2020.09.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 06/03/2023]
Abstract
BACKGROUND The development of treatments for cognitive deficits associated with central nervous system disorders is currently a significant medical need. Despite the great need for such therapeutics, a significant challenge in the drug development process is the paucity of robust biomarkers to assess target modulation and guide clinical decisions. We developed a novel, translatable biomarker of neuronal glutamate metabolism, the 13C-glutamate+glutamine (Glx) H3:H4 labeling ratio, in nonhuman primates using localized 1H-magnetic resonance spectroscopy combined with 13C-glucose infusions. METHODS We began with numerical simulations in an established model of brain glutamate metabolism, showing that the 13C-Glx H3:H4 ratio should be a sensitive biomarker of neuronal tricarboxylic acid cycle activity, a key measure of overall neuronal metabolism. We showed that this biomarker can be measured reliably using a standard 1H-magnetic resonance spectroscopy method (point-resolved spectroscopy sequence/echo time = 20 ms), obviating the need for specialized hardware and pulse sequences typically used with 13C-magnetic resonance spectroscopy, thus improving overall clinical translatability. Finally, we used this biomarker in 8 male rhesus macaques before and after administration of the compound BNC375, a positive allosteric modulator of the α7 nicotinic acetylcholine receptor that enhances glutamate signaling ex vivo and elicits procognitive effects in preclinical species. RESULTS The 13C-Glx H3:H4 ratios in the monkeys showed that BNC375 increases neuronal metabolism in nonhuman primates in vivo, detectable on an individual basis. CONCLUSIONS This study demonstrates that the ratio of 13C-Glx H3:H4 labeling is a biomarker that may provide an objective readout of compounds affecting glutamatergic neurotransmission and could improve decision making for the development of therapeutic agents.
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Affiliation(s)
- Corin O Miller
- Department of Translational Imaging Biomarkers, Merck & Co., Kenilworth, New Jersey.
| | - Liza T Gantert
- Department of Translational Imaging Biomarkers, Merck & Co., Kenilworth, New Jersey
| | | | - Ying Chen
- Department of Chemistry, Merck & Co., Kenilworth, New Jersey
| | - Kenneth D Anderson
- Department of Pharmacology, Pharmacokinetics, and Drug Metabolism, Merck & Co., Kenilworth, New Jersey
| | - Justina M Thomas
- Department of Pharmacology, Pharmacokinetics, and Drug Metabolism, Merck & Co., Kenilworth, New Jersey
| | - Gerard Sanacora
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Jason M Uslaner
- Department of Neuroscience, Merck & Co., Kenilworth, New Jersey
| | - Douglas L Rothman
- Department of Diagnostic Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut; Department of Biomedical Engineering Yale University School of Medicine, New Haven, Connecticut
| | - Graeme F Mason
- Department of Diagnostic Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
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3
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Soni ND, Ramesh A, Roy D, Patel AB. Brain energy metabolism in intracerebroventricularly administered streptozotocin mouse model of Alzheimer's disease: A 1H-[ 13C]-NMR study. J Cereb Blood Flow Metab 2021; 41:2344-2355. [PMID: 33657898 PMCID: PMC8393290 DOI: 10.1177/0271678x21996176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer's disease (AD) is a very common neurodegenerative disorder. Although a majority of the AD cases are sporadic, most of the studies are conducted using transgenic models. Intracerebroventricular (ICV) administered streptozotocin (STZ) animals have been used to explore mechanisms in sporadic AD. In this study, we have investigated memory and neurometabolism of ICV-STZ-administered C57BL6/J mice. The neuronal and astroglial metabolic activity was measured in 1H-[13C]-NMR spectrum of cortical and hippocampal tissue extracts of mice infused with [1,6-13C2]glucose and [2-13C]acetate, respectively. STZ-administered mice exhibited reduced (p = 0.00002) recognition index for memory. The levels of creatine, GABA, glutamate and NAA were reduced (p ≤ 0.04), while that of myo-inositol was increased (p < 0.05) in STZ-treated mice. There was a significant (p ≤ 0.014) reduction in aspartate-C3, glutamate-C4/C3, GABA-C2 and glutamine-C4 labeling from [1,6-13C2]glucose. This resulted in decreased rate of glucose oxidation in the cerebral cortex (0.64 ± 0.05 vs. 0.77 ± 0.05 µmol/g/min, p = 0.0008) and hippocampus (0.60 ± 0.04 vs. 0.73 ± 0.07 µmol/g/min, p = 0.001) of STZ-treated mice, due to similar reductions of glucose oxidation in glutamatergic and GABAergic neurons. Additionally, reduced glutamine-C4 labeling points towards compromised synaptic neurotransmission in STZ-treated mice. These data suggest that the ICV-STZ model exhibits neurometabolic deficits typically observed in AD, and its utility in understanding the mechanism of sporadic AD.
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Affiliation(s)
- Narayan D Soni
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Akila Ramesh
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Dipak Roy
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Anant B Patel
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
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4
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Cherix A, Sonti R, Lanz B, Lei H. In Vivo Metabolism of [1,6- 13C 2]Glucose Reveals Distinct Neuroenergetic Functionality between Mouse Hippocampus and Hypothalamus. Metabolites 2021; 11:metabo11010050. [PMID: 33445747 PMCID: PMC7828183 DOI: 10.3390/metabo11010050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 12/27/2022] Open
Abstract
Glucose is a major energy fuel for the brain, however, less is known about specificities of its metabolism in distinct cerebral areas. Here we examined the regional differences in glucose utilization between the hypothalamus and hippocampus using in vivo indirect 13C magnetic resonance spectroscopy (1H-[13C]-MRS) upon infusion of [1,6-13C2]glucose. Using a metabolic flux analysis with a 1-compartment mathematical model of brain metabolism, we report that compared to hippocampus, hypothalamus shows higher levels of aerobic glycolysis associated with a marked gamma-aminobutyric acid-ergic (GABAergic) and astrocytic metabolic dependence. In addition, our analysis suggests a higher rate of ATP production in hypothalamus that is accompanied by an excess of cytosolic nicotinamide adenine dinucleotide (NADH) production that does not fuel mitochondria via the malate-aspartate shuttle (MAS). In conclusion, our results reveal significant metabolic differences, which might be attributable to respective cell populations or functional features of both structures.
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Affiliation(s)
- Antoine Cherix
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland; (A.C.); (R.S.); (B.L.)
| | - Rajesh Sonti
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland; (A.C.); (R.S.); (B.L.)
| | - Bernard Lanz
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland; (A.C.); (R.S.); (B.L.)
| | - Hongxia Lei
- Animal Imaging and Technology (AIT), Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Faculty of Medicine, University of Geneva, CH-1206 Geneva, Switzerland
- Correspondence:
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5
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Lanz B, Abaei A, Braissant O, Choi IY, Cudalbu C, Henry PG, Gruetter R, Kara F, Kantarci K, Lee P, Lutz NW, Marjańska M, Mlynárik V, Rasche V, Xin L, Valette J. Magnetic resonance spectroscopy in the rodent brain: Experts' consensus recommendations. NMR IN BIOMEDICINE 2020; 34:e4325. [PMID: 33565219 PMCID: PMC9429976 DOI: 10.1002/nbm.4325] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/29/2020] [Accepted: 04/30/2020] [Indexed: 05/21/2023]
Abstract
In vivo MRS is a non-invasive measurement technique used not only in humans, but also in animal models using high-field magnets. MRS enables the measurement of metabolite concentrations as well as metabolic rates and their modifications in healthy animals and disease models. Such data open the way to a deeper understanding of the underlying biochemistry, related disturbances and mechanisms taking place during or prior to symptoms and tissue changes. In this work, we focus on the main preclinical 1H, 31P and 13C MRS approaches to study brain metabolism in rodent models, with the aim of providing general experts' consensus recommendations (animal models, anesthesia, data acquisition protocols). An overview of the main practical differences in preclinical compared with clinical MRS studies is presented, as well as the additional biochemical information that can be obtained in animal models in terms of metabolite concentrations and metabolic flux measurements. The properties of high-field preclinical MRS and the technical limitations are also described.
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Affiliation(s)
- Bernard Lanz
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Alireza Abaei
- Core Facility Small Animal Imaging, Ulm University, Ulm, Germany
| | - Olivier Braissant
- Service of Clinical Chemistry, University of Lausanne and University Hospital of Lausanne, Lausanne, Switzerland
| | - In-Young Choi
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, US
| | - Cristina Cudalbu
- Centre d’Imagerie Biomedicale (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Pierre-Gilles Henry
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, US
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Firat Kara
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, US
| | - Kejal Kantarci
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, US
| | - Phil Lee
- Department of Radiology, University of Kansas Medical Center, Kansas City, Kansas, US
| | | | - Małgorzata Marjańska
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, US
| | - Vladimír Mlynárik
- High Field MR Centre, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Volker Rasche
- Core Facility Small Animal Imaging, Ulm University, Ulm, Germany
| | - Lijing Xin
- Centre d’Imagerie Biomedicale (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Julien Valette
- Commissariat à l’Energie Atomique et aux Energies Alternatives, MIRCen, Fontenay-aux-Roses, France
- Neurodegenerative Diseases Laboratory, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Fontenay-aux-Roses, France
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6
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Lizarbe B, Cherix A, Duarte JMN, Cardinaux JR, Gruetter R. High-fat diet consumption alters energy metabolism in the mouse hypothalamus. Int J Obes (Lond) 2018; 43:1295-1304. [PMID: 30301962 DOI: 10.1038/s41366-018-0224-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 08/14/2018] [Accepted: 08/29/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND/OBJECTIVES High-fat diet consumption is known to trigger an inflammatory response in the hypothalamus, which has been characterized by an initial expression of pro-inflammatory genes followed by hypothalamic astrocytosis, microgliosis, and the appearance of neuronal injury markers. The specific effects of high-fat diet on hypothalamic energy metabolism and neurotransmission are however not yet known and have not been investigated before. SUBJECTS/METHODS We used 1H and 13C magnetic resonance spectroscopy (MRS) and immunofluorescence techniques to evaluate in vivo the consequences of high-saturated fat diet administration to mice, and explored the effects on hypothalamic metabolism in three mouse cohorts at different time points for up to 4 months. RESULTS We found that high-fat diet increases significantly the hypothalamic levels of glucose (P < 0.001), osmolytes (P < 0.001), and neurotransmitters (P < 0.05) from 2 months of diet, and alters the rates of metabolic (P < 0.05) and neurotransmission fluxes (P < 0.001), and the contribution of non-glycolytic substrates to hypothalamic metabolism (P < 0.05) after 10 weeks of high-fat feeding. CONCLUSIONS/INTERPRETATION We report changes that reveal a high-fat diet-induced alteration of hypothalamic metabolism and neurotransmission that is quantifiable by 1H and 13C MRS in vivo, and present the first evidence of the extension of the inflammation pathology to a localized metabolic imbalance.
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Affiliation(s)
- Blanca Lizarbe
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Antoine Cherix
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - João M N Duarte
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Department of Experimental Medical Science, Faculty of Medicine, Lund University, Lund, Sweden.,Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Jean-René Cardinaux
- Center for Psychiatric Neuroscience (CNP), Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - Rolf Gruetter
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Department of Radiology, University of Geneva, Geneva, Switzerland.,Department of Radiology, University of Lausanne, Lausanne, Switzerland
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7
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Kumaragamage C, Madularu D, Mathieu AP, Lupinsky D, de Graaf RA, Near J. Minimum echo time PRESS-based proton observed carbon edited (POCE) MRS in rat brain using simultaneous editing and localization pulses. Magn Reson Med 2018; 80:1279-1288. [DOI: 10.1002/mrm.27119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/22/2017] [Accepted: 01/14/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Chathura Kumaragamage
- Department of Biomedical Engineering; McGill University; Montreal Quebec Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal Quebec Canada
| | - Dan Madularu
- Department of Psychiatry, Faculty of Medicine; McGill University; Montreal Quebec Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal Quebec Canada
- Center for Translational NeuroImaging; Northeastern University; Boston Massachusetts USA
| | - Axel P. Mathieu
- Department of Psychiatry, Faculty of Medicine; McGill University; Montreal Quebec Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal Quebec Canada
| | - Derek Lupinsky
- Department of Psychiatry, Faculty of Medicine; McGill University; Montreal Quebec Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal Quebec Canada
| | - Robin A. de Graaf
- Radiology and Biomedical Imaging; Yale University; New Haven Connecticut USA
| | - Jamie Near
- Department of Biomedical Engineering; McGill University; Montreal Quebec Canada
- Department of Psychiatry, Faculty of Medicine; McGill University; Montreal Quebec Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal Quebec Canada
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8
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Lizarbe B, Lei H, Duarte JM, Lanz B, Cherix A, Gruetter R. Feasibility of in vivo measurement of glucose metabolism in the mouse hypothalamus by1H-[13C] MRS at 14.1T. Magn Reson Med 2018; 80:874-884. [DOI: 10.1002/mrm.27129] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/22/2018] [Accepted: 01/22/2018] [Indexed: 12/24/2022]
Affiliation(s)
- Blanca Lizarbe
- Laboratory of Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Hongxia Lei
- Department of Radiology; University of Geneva, Geneva, Switzerland and Center for Biomedical Imaging (CIBM); Lausanne Switzerland
| | - Joao M.N. Duarte
- Laboratory of Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Bernard Lanz
- Laboratory of Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham; Nottingham United Kingdom
| | - Antoine Cherix
- Laboratory of Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Rolf Gruetter
- Laboratory of Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Department of Radiology; University of Geneva, Geneva, Switzerland and Center for Biomedical Imaging (CIBM); Lausanne Switzerland
- Department of Radiology; University of Lausanne; Lausanne Switzerland
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9
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Abstract
Magnetic Resonance Spectroscopy is a technique that has the capability of measuring metabolites in vivo and, in appropriate conditions, to infer its metabolic rates. The success of MRS depends a lot on its sensitivity, which limits the usage of X-nuclei MRS. However, technological developments and refinements in methods have made in vivo heteronuclear MRS possible in humans and in small animals. This chapter provides detailed descriptions of the main procedures needed to perform successful in vivo heteronuclear MRS experiments, with a particular focus on experimental setup in 13C MRS experiments in rodents.
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Affiliation(s)
- Blanca Lizarbe
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Antoine Cherix
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Department of Radiology, University of Geneva, Geneva, Switzerland.,Department of Radiology, University of Lausanne, Lausanne, Switzerland
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10
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De Feyter HM, Herzog RI, Steensma BR, Klomp DWJ, Brown PB, Mason GF, Rothman DL, de Graaf RA. Selective proton-observed, carbon-edited (selPOCE) MRS method for measurement of glutamate and glutamine 13 C-labeling in the human frontal cortex. Magn Reson Med 2017; 80:11-20. [PMID: 29134686 DOI: 10.1002/mrm.27003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 10/02/2017] [Accepted: 10/20/2017] [Indexed: 11/10/2022]
Abstract
PURPOSE 13 C magnetic resonance spectroscopy (MRS) in combination with infusion of 13 C-labeled substrates has led to unique insights into human brain metabolism and neurotransmitter cycling. However, the low sensitivity of direct 13 C MRS and high radiofrequency power requirements has limited 13 C MRS studies to predominantly data acquisition in large volumes of the occipital cortex. The purpose of this study is to develop an MRS technique for localized detection of 13 C-labeling of glutamate and glutamine in the human frontal lobe. METHODS We used an indirect (1 H-[13 C]), proton-observed, carbon-edited MRS sequence (selPOCE) for detection of 13 C-labeled metabolites in relatively small volumes located in the frontal lobe at 4 T. The SelPOCE method allows for selective and separate detection of glutamate and glutamine resonances, which significantly overlap at magnetic field strengths used for clinical MRI. RESULTS Phantom data illustrate how selPOCE can be tuned to selectively detect 13 C labeling in different metabolites. Three-dimensional specific absorption rate simulations of radiofrequency power deposition show that the selPOCE method operates comfortably within the global and local Food and Drug Administration specific absorption rate guidelines. In vivo selPOCE data are presented, which were acquired from a 45-mL volume in the frontal lobe of healthy subjects. The in vivo data show the time-dependent 13 C-labeling of glutamate and glutamine during intravenous infusion of [1-13 C]-glucose. Metrics describing spectral fitting quality of the glutamate and glutamine resonances are reported. CONCLUSIONS The SelPOCE sequence allows the detection of 13 C-labeling in glutamate and glutamine from a relatively small volume in the human frontal lobe at low radiofrequency power requirements. Magn Reson Med 80:11-20, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Henk M De Feyter
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Raimund I Herzog
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Bart R Steensma
- Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Dennis W J Klomp
- Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Peter B Brown
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Graeme F Mason
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Douglas L Rothman
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Robin A de Graaf
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
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11
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Lanz B, Rackayova V, Braissant O, Cudalbu C. MRS studies of neuroenergetics and glutamate/glutamine exchange in rats: Extensions to hyperammonemic models. Anal Biochem 2017; 529:245-269. [DOI: 10.1016/j.ab.2016.11.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 11/16/2016] [Accepted: 11/30/2016] [Indexed: 01/27/2023]
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12
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Kumaragamage C, Madularu D, Mathieu AP, De Feyter H, Rajah MN, Near J. In vivo proton observed carbon edited (POCE) 13
C magnetic resonance spectroscopy of the rat brain using a volumetric transmitter and receive-only surface coil on the proton channel. Magn Reson Med 2017; 79:628-635. [DOI: 10.1002/mrm.26751] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/15/2017] [Accepted: 04/19/2017] [Indexed: 12/25/2022]
Affiliation(s)
- Chathura Kumaragamage
- Department of Biomedical Engineering; McGill University; Montreal QC Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal QC Canada
| | - Dan Madularu
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal QC Canada
- Department of Psychiatry; Faculty of Medicine, McGill University; Montreal QC Canada
| | - Axel P. Mathieu
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal QC Canada
- Department of Psychiatry; Faculty of Medicine, McGill University; Montreal QC Canada
| | - Henk De Feyter
- Radiology and Biomedical Imaging; Yale University; New Haven Connecticut USA
| | - M. Natasha Rajah
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal QC Canada
- Department of Psychiatry; Faculty of Medicine, McGill University; Montreal QC Canada
- Department of Psychology; Faculty of Arts, McGill University; Montreal QC Canada
| | - Jamie Near
- Department of Biomedical Engineering; McGill University; Montreal QC Canada
- Brain Imaging Centre; Douglas Mental Health University Institute, McGill University; Montreal QC Canada
- Department of Psychiatry; Faculty of Medicine, McGill University; Montreal QC Canada
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Lai M, Gruetter R, Lanz B. Progress towards in vivo brain 13C-MRS in mice: Metabolic flux analysis in small tissue volumes. Anal Biochem 2017; 529:229-244. [PMID: 28119064 DOI: 10.1016/j.ab.2017.01.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 01/08/2023]
Abstract
The combination of dynamic 13C MRS data under infusion of 13C-labelled substrates and compartmental models of cerebral metabolism enabled in vivo measurement of metabolic fluxes with a quantitative and distinct determination of cellular-specific activities. The non-invasive nature and the chemical specificity of the 13C dynamic data obtained in those tracer experiments makes it an attractive approach offering unique insights into cerebral metabolism. Genetically engineered mice present a wealth of disease models particularly interesting for the neuroscience community. Nevertheless, in vivo13C NMR studies of the mouse brain are only recently appearing in the field due to the numerous challenges linked to the small mouse brain volume and the difficulty to follow the mouse physiological parameters within the NMR system during the infusion experiment. This review will present the progresses in the quest for a higher in vivo13C signal-to-noise ratio up to the present state of the art techniques, which made it feasible to assess glucose metabolism in different regions of the mouse brain. We describe how experimental results were integrated into suitable compartmental models and how a deep understanding of cerebral metabolism depends on the reliable detection of 13C in the different molecules and carbon positions.
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Affiliation(s)
- Marta Lai
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland; Department of Radiology, University of Geneva, 1205 Geneva, Switzerland; Department of Radiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Bernard Lanz
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland; Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom
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Dehghani M M, Lanz B, Duarte JMN, Kunz N, Gruetter R. Refined Analysis of Brain Energy Metabolism Using In Vivo Dynamic Enrichment of 13C Multiplets. ASN Neuro 2016; 8:8/2/1759091416632342. [PMID: 26969691 PMCID: PMC4790427 DOI: 10.1177/1759091416632342] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/30/2015] [Indexed: 11/18/2022] Open
Abstract
Carbon-13 nuclear magnetic resonance spectroscopy in combination with the infusion of 13C-labeled precursors is a unique approach to study in vivo brain energy metabolism. Incorporating the maximum information available from in vivo localized 13C spectra is of importance to get broader knowledge on cerebral metabolic pathways. Metabolic rates can be quantitatively determined from the rate of 13C incorporation into amino acid neurotransmitters such as glutamate and glutamine using suitable mathematical models. The time course of multiplets arising from 13C-13C coupling between adjacent carbon atoms was expected to provide additional information for metabolic modeling leading to potential improvements in the estimation of metabolic parameters. The aim of the present study was to extend two-compartment neuronal/glial modeling to include dynamics of 13C isotopomers available from fine structure multiplets in 13C spectra of glutamate and glutamine measured in vivo in rats brain at 14.1 T, termed bonded cumomer approach. Incorporating the labeling time courses of 13C multiplets of glutamate and glutamine resulted in elevated precision of the estimated fluxes in rat brain as well as reduced correlations between them.
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Affiliation(s)
- Masoumeh Dehghani M
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
| | - Bernard Lanz
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
| | - João M N Duarte
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland Department of Radiology, University of Lausanne, Switzerland
| | - Nicolas Kunz
- CIBM-AIT, Ecole Polytechnique Fédérale de Lausanne, Switzerland
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland Department of Radiology, University of Lausanne, Switzerland Department of Radiology, University of Geneva, Switzerland
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Xin L, Lanz B, Lei H, Gruetter R. Assessment of metabolic fluxes in the mouse brain in vivo using 1H-[13C] NMR spectroscopy at 14.1 Tesla. J Cereb Blood Flow Metab 2015; 35:759-65. [PMID: 25605294 PMCID: PMC4420852 DOI: 10.1038/jcbfm.2014.251] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 11/27/2014] [Accepted: 12/15/2014] [Indexed: 01/13/2023]
Abstract
(13)C magnetic resonance spectroscopy (MRS) combined with the administration of (13)C labeled substrates uniquely allows to measure metabolic fluxes in vivo in the brain of humans and rats. The extension to mouse models may provide exclusive prospect for the investigation of models of human diseases. In the present study, the short-echo-time (TE) full-sensitivity (1)H-[(13)C] MRS sequence combined with high magnetic field (14.1 T) and infusion of [U-(13)C6] glucose was used to enhance the experimental sensitivity in vivo in the mouse brain and the (13)C turnover curves of glutamate C4, glutamine C4, glutamate+glutamine C3, aspartate C2, lactate C3, alanine C3, γ-aminobutyric acid C2, C3 and C4 were obtained. A one-compartment model was used to fit (13)C turnover curves and resulted in values of metabolic fluxes including the tricarboxylic acid (TCA) cycle flux VTCA (1.05 ± 0.04 μmol/g per minute), the exchange flux between 2-oxoglutarate and glutamate Vx (0.48 ± 0.02 μmol/g per minute), the glutamate-glutamine exchange rate V(gln) (0.20 ± 0.02 μmol/g per minute), the pyruvate dilution factor K(dil) (0.82 ± 0.01), and the ratio for the lactate conversion rate and the alanine conversion rate V(Lac)/V(Ala) (10 ± 2). This study opens the prospect of studying transgenic mouse models of brain pathologies.
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Affiliation(s)
- Lijing Xin
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Unit for Research in Schizophrenia, Department of Psychiatry, Center for Psychiatric Neuroscience, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Bernard Lanz
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Hongxia Lei
- Department of Radiology, University of Geneva, Geneva, Switzerland
- Animal Imaging and Technology Core (AIT), Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Rolf Gruetter
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Radiology, University of Geneva, Geneva, Switzerland
- Department of Radiology, University of Lausanne, Lausanne, Switzerland
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Lanz B, Xin L, Millet P, Gruetter R. In vivo quantification of neuro-glial metabolism and glial glutamate concentration using 1H-[13C] MRS at 14.1T. J Neurochem 2013; 128:125-39. [PMID: 24117599 DOI: 10.1111/jnc.12479] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 08/31/2013] [Accepted: 09/19/2013] [Indexed: 12/12/2022]
Abstract
Astrocytes have recently become a major center of interest in neurochemistry with the discoveries on their major role in brain energy metabolism. An interesting way to probe this glial contribution is given by in vivo (13) C NMR spectroscopy coupled with the infusion labeled glial-specific substrate, such as acetate. In this study, we infused alpha-chloralose anesthetized rats with [2-(13) C]acetate and followed the dynamics of the fractional enrichment (FE) in the positions C4 and C3 of glutamate and glutamine with high sensitivity, using (1) H-[(13) C] magnetic resonance spectroscopy (MRS) at 14.1T. Applying a two-compartment mathematical model to the measured time courses yielded a glial tricarboxylic acid (TCA) cycle rate (Vg ) of 0.27 ± 0.02 μmol/g/min and a glutamatergic neurotransmission rate (VNT ) of 0.15 ± 0.01 μmol/g/min. Glial oxidative ATP metabolism thus accounts for 38% of total oxidative metabolism measured by NMR. Pyruvate carboxylase (VPC ) was 0.09 ± 0.01 μmol/g/min, corresponding to 37% of the glial glutamine synthesis rate. The glial and neuronal transmitochondrial fluxes (Vx (g) and Vx (n) ) were of the same order of magnitude as the respective TCA cycle fluxes. In addition, we estimated a glial glutamate pool size of 0.6 ± 0.1 μmol/g. The effect of spectral data quality on the fluxes estimates was analyzed by Monte Carlo simulations. In this (13) C-acetate labeling study, we propose a refined two-compartment analysis of brain energy metabolism based on (13) C turnover curves of acetate, glutamate and glutamine measured with state of the art in vivo dynamic MRS at high magnetic field in rats, enabling a deeper understanding of the specific role of glial cells in brain oxidative metabolism. In addition, the robustness of the metabolic fluxes determination relative to MRS data quality was carefully studied.
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Affiliation(s)
- Bernard Lanz
- Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Tiwari V, Ambadipudi S, Patel AB. Glutamatergic and GABAergic TCA cycle and neurotransmitter cycling fluxes in different regions of mouse brain. J Cereb Blood Flow Metab 2013; 33:1523-31. [PMID: 23838829 PMCID: PMC3790929 DOI: 10.1038/jcbfm.2013.114] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/22/2013] [Accepted: 06/14/2013] [Indexed: 11/09/2022]
Abstract
The (13)C nuclear magnetic resonance (NMR) studies together with the infusion of (13)C-labeled substrates in rats and humans have provided important insight into brain energy metabolism. In the present study, we have extended a three-compartment metabolic model in mouse to investigate glutamatergic and GABAergic tricarboxylic acid (TCA) cycle and neurotransmitter cycle fluxes across different regions of the brain. The (13)C turnover of amino acids from [1,6-(13)C2]glucose was monitored ex vivo using (1)H-[(13)C]-NMR spectroscopy. The astroglial glutamate pool size, one of the important parameters of the model, was estimated by a short infusion of [2-(13)C]acetate. The ratio Vcyc/VTCA was calculated from the steady-state acetate experiment. The (13)C turnover curves of [4-(13)C]/[3-(13)C]glutamate, [4-(13)C]glutamine, [2-(13)C]/[3-(13)C]GABA, and [3-(13)C]aspartate from [1,6-(13)C2]glucose were analyzed using a three-compartment metabolic model to estimate the rates of the TCA cycle and neurotransmitter cycle associated with glutamatergic and GABAergic neurons. The glutamatergic TCA cycle rate was found to be highest in the cerebral cortex (0.91 ± 0.05 μmol/g per minute) and least in the hippocampal region (0.64 ± 0.07 μmol/g per minute) of the mouse brain. In contrast, the GABAergic TCA cycle flux was found to be highest in the thalamus-hypothalamus (0.28 ± 0.01 μmol/g per minute) and least in the cerebral cortex (0.24 ± 0.02 μmol/g per minute). These findings indicate that the energetics of excitatory and inhibitory function is distinct across the mouse brain.
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Affiliation(s)
- Vivek Tiwari
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Habsiguda India
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Duarte JMN, Gruetter R. Glutamatergic and GABAergic energy metabolism measured in the rat brain by 13
C NMR spectroscopy at 14.1 T. J Neurochem 2013; 126:579-90. [DOI: 10.1111/jnc.12333] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 06/05/2013] [Accepted: 06/06/2013] [Indexed: 12/11/2022]
Affiliation(s)
- João M. N. Duarte
- Laboratory for Functional and Metabolic Imaging; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Department of Radiology; University of Lausanne; Lausanne Switzerland
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Department of Radiology; University of Lausanne; Lausanne Switzerland
- Department of Radiology; University of Geneva; Geneva Switzerland
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The neurochemical profile quantified by in vivo 1H NMR spectroscopy. Neuroimage 2012; 61:342-62. [DOI: 10.1016/j.neuroimage.2011.12.038] [Citation(s) in RCA: 168] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 12/15/2011] [Indexed: 12/13/2022] Open
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Duarte JMN, Lanz B, Gruetter R. Compartmentalized Cerebral Metabolism of [1,6-(13)C]Glucose Determined by in vivo (13)C NMR Spectroscopy at 14.1 T. FRONTIERS IN NEUROENERGETICS 2011; 3:3. [PMID: 21713114 PMCID: PMC3112327 DOI: 10.3389/fnene.2011.00003] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 05/17/2011] [Indexed: 11/13/2022]
Abstract
Cerebral metabolism is compartmentalized between neurons and glia. Although glial glycolysis is thought to largely sustain the energetic requirements of neurotransmission while oxidative metabolism takes place mainly in neurons, this hypothesis is matter of debate. The compartmentalization of cerebral metabolic fluxes can be determined by (13)C nuclear magnetic resonance (NMR) spectroscopy upon infusion of (13)C-enriched compounds, especially glucose. Rats under light α-chloralose anesthesia were infused with [1,6-(13)C]glucose and (13)C enrichment in the brain metabolites was measured by (13)C NMR spectroscopy with high sensitivity and spectral resolution at 14.1 T. This allowed determining (13)C enrichment curves of amino acid carbons with high reproducibility and to reliably estimate cerebral metabolic fluxes (mean error of 8%). We further found that TCA cycle intermediates are not required for flux determination in mathematical models of brain metabolism. Neuronal tricarboxylic acid cycle rate (V(TCA)) and neurotransmission rate (V(NT)) were 0.45 ± 0.01 and 0.11 ± 0.01 μmol/g/min, respectively. Glial V(TCA) was found to be 38 ± 3% of total cerebral oxidative metabolism, accounting for more than half of neuronal oxidative metabolism. Furthermore, glial anaplerotic pyruvate carboxylation rate (V(PC)) was 0.069 ± 0.004 μmol/g/min, i.e., 25 ± 1% of the glial TCA cycle rate. These results support a role of glial cells as active partners of neurons during synaptic transmission beyond glycolytic metabolism.
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Affiliation(s)
- João M N Duarte
- Center for Biomedical Imaging, Ecole Polytechnique Fédérale de Lausanne Lausanne, Switzerland
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Prompers JJ, Strijkers GJ, Nicolay K. Magnetic resonance spectroscopy of in vivo tissue metabolism in small animals. DRUG DISCOVERY TODAY. TECHNOLOGIES 2011; 8:e95-e102. [PMID: 24990268 DOI: 10.1016/j.ddtec.2011.11.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- Jeanine J Prompers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
| | - Gustav J Strijkers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Klaas Nicolay
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
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