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Bottino F, Lucignani M, Napolitano A, Dellepiane F, Visconti E, Rossi Espagnet MC, Pasquini L. In Vivo Brain GSH: MRS Methods and Clinical Applications. Antioxidants (Basel) 2021; 10:antiox10091407. [PMID: 34573039 PMCID: PMC8468877 DOI: 10.3390/antiox10091407] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/22/2021] [Accepted: 08/30/2021] [Indexed: 01/31/2023] Open
Abstract
Glutathione (GSH) is an important antioxidant implicated in several physiological functions, including the oxidation−reduction reaction balance and brain antioxidant defense against endogenous and exogenous toxic agents. Altered brain GSH levels may reflect inflammatory processes associated with several neurologic disorders. An accurate and reliable estimation of cerebral GSH concentrations could give a clear and thorough understanding of its metabolism within the brain, thus providing a valuable benchmark for clinical applications. In this context, we aimed to provide an overview of the different magnetic resonance spectroscopy (MRS) technologies introduced for in vivo human brain GSH quantification both in healthy control (HC) volunteers and in subjects affected by different neurological disorders (e.g., brain tumors, and psychiatric and degenerative disorders). Additionally, we aimed to provide an exhaustive list of normal GSH concentrations within different brain areas. The definition of standard reference values for different brain areas could lead to a better interpretation of the altered GSH levels recorded in subjects with neurological disorders, with insights into the possible role of GSH as a biomarker and therapeutic target.
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Affiliation(s)
- Francesca Bottino
- Medical Physics Department, Bambino Gesù Children’s Hospital IRCCS, 00165 Rome, Italy; (F.B.); (M.L.)
| | - Martina Lucignani
- Medical Physics Department, Bambino Gesù Children’s Hospital IRCCS, 00165 Rome, Italy; (F.B.); (M.L.)
| | - Antonio Napolitano
- Medical Physics Department, Bambino Gesù Children’s Hospital IRCCS, 00165 Rome, Italy; (F.B.); (M.L.)
- Correspondence: ; Tel.: +39-333-3214614
| | - Francesco Dellepiane
- Neuroradiology Unit, NESMOS Department, Sant’Andrea Hospital, La Sapienza University, 00189 Rome, Italy; (F.D.); (M.C.R.E.); (L.P.)
| | - Emiliano Visconti
- Neuroradiology Unit, Surgery and Trauma Department, Maurizio Bufalini Hospital, 47521 Cesena, Italy;
| | - Maria Camilla Rossi Espagnet
- Neuroradiology Unit, NESMOS Department, Sant’Andrea Hospital, La Sapienza University, 00189 Rome, Italy; (F.D.); (M.C.R.E.); (L.P.)
- Neuroradiology Unit, Bambino Gesù Children’s Hospital IRCCS, 00165 Rome, Italy
| | - Luca Pasquini
- Neuroradiology Unit, NESMOS Department, Sant’Andrea Hospital, La Sapienza University, 00189 Rome, Italy; (F.D.); (M.C.R.E.); (L.P.)
- Neuroradiology Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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Choi IY, Andronesi OC, Barker P, Bogner W, Edden RAE, Kaiser LG, Lee P, Marjańska M, Terpstra M, de Graaf RA. Spectral editing in 1 H magnetic resonance spectroscopy: Experts' consensus recommendations. NMR IN BIOMEDICINE 2021; 34:e4411. [PMID: 32946145 PMCID: PMC8557623 DOI: 10.1002/nbm.4411] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 05/08/2023]
Abstract
Spectral editing in in vivo 1 H-MRS provides an effective means to measure low-concentration metabolite signals that cannot be reliably measured by conventional MRS techniques due to signal overlap, for example, γ-aminobutyric acid, glutathione and D-2-hydroxyglutarate. Spectral editing strategies utilize known J-coupling relationships within the metabolite of interest to discriminate their resonances from overlying signals. This consensus recommendation paper provides a brief overview of commonly used homonuclear editing techniques and considerations for data acquisition, processing and quantification. Also, we have listed the experts' recommendations for minimum requirements to achieve adequate spectral editing and reliable quantification. These include selecting the right editing sequence, dealing with frequency drift, handling unwanted coedited resonances, spectral fitting of edited spectra, setting up multicenter clinical trials and recommending sequence parameters to be reported in publications.
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Affiliation(s)
- In-Young Choi
- Department of Neurology, Hoglund Biomedical Imaging Center, University of Kansas Medical Center, Kansas City, Kansas
| | - Ovidiu C Andronesi
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Peter Barker
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, F. M. Kirby Center for Functional MRI, Kennedy Krieger Institute, Baltimore, Maryland
| | - Wolfgang Bogner
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Richard A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, F. M. Kirby Center for Functional MRI, Kennedy Krieger Institute, Baltimore, Maryland
| | - Lana G Kaiser
- Henry H. Wheeler, Jr. Brain Imaging Center, University of California, Berkeley, California
| | - Phil Lee
- Department of Radiology, Hoglund Biomedical Imaging Center, University of Kansas Medical Center, Kansas City, Kansas
| | - Małgorzata Marjańska
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota
| | - Melissa Terpstra
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota
| | - Robin A de Graaf
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut
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Landheer K, Schulte RF, Treacy MS, Swanberg KM, Juchem C. Theoretical description of modern1H in Vivo magnetic resonance spectroscopic pulse sequences. J Magn Reson Imaging 2019; 51:1008-1029. [DOI: 10.1002/jmri.26846] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 01/20/2023] Open
Affiliation(s)
- Karl Landheer
- Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science New York New York USA
| | | | - Michael S. Treacy
- Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science New York New York USA
| | - Kelley M. Swanberg
- Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science New York New York USA
| | - Christoph Juchem
- Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science New York New York USA
- Radiology, Columbia University College of Physicians and Surgeons New York New York USA
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Simpson T, Deleuil S, Echeverria N, Komanduri M, Macpherson H, Suo C, Gondalia S, Fard MT, Pipingas A, Scholey A, Stough C. The Australian Research Council Longevity Intervention (ARCLI) study protocol (ANZCTR12611000487910) addendum: neuroimaging and gut microbiota protocol. Nutr J 2019; 18:1. [PMID: 30611275 PMCID: PMC6321680 DOI: 10.1186/s12937-018-0428-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 12/20/2018] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The Australian Research Council Longevity Intervention (ARCLI) was designed to investigate the effects of two active supplements, Pycnogenol and Bacopa monnieri (CDRI08) on cognitive performance in a cohort of elderly participants. An additional antioxidant supplement has been included into the trial. A neuroimaging component has also been added to the ARCLI study to investigate the neurochemical biomarkers of oxidative stress in vivo, as well as structural and functional changes associated with ageing and oxidative stress. Faecal biomarkers of gut microflora will also be analysed to investigate if gut microbiota are associated with domains of cognition (e.g., attention, processing speed, memory), mood or other ARCLI outcome variables. The aim of this paper is to update the published methods of the ARCLI clinical trial before it is completed, and data analysis commences. METHODS ARCLI is a randomised, placebo controlled, double-blind, now 4-arm clinical trial including neuroimaging and gut microflora sub-studies. Along with the demographic, haematological, mood, cardiovascular and cognitive assessments described in the initial protocol, 80 eligible participants from the overall study pool of ~ 400 will be recruited into the neuroimaging study and undergo scans at baseline, 3 months and 12 months. Proton magnetic resonance spectroscopy, resting state functional connectivity and arterial spin labelled perfusion sequences are neuroimaging techniques included for each MRI visit in the study. Similarly, approximately 300 participants from the main study pool will be recruited to provide faecal samples at baseline, 3 months and 12 months so that the gut microbiome can be studied. DISCUSSION ARCLI is 12-month intervention study, currently underway with a group of older adults, investigating a range of outcomes and their association with ageing. The additional measurements in the ARCLI trial will further the understanding of the underlying mechanisms associated with healthy ageing and may provide insights into novel preventative therapeutic strategies for maintaining cognitive and brain health into old age. TRIAL REGISTRATION Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000487970 .
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Affiliation(s)
- Tamara Simpson
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Saurenne Deleuil
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Nicole Echeverria
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Mrudhula Komanduri
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Helen Macpherson
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
- Institute for Physical Activity and Nutrition Research, Deakin University, Melbourne, Australia
| | - Chao Suo
- Brain and Mental Health Laboratory, Monash Institute of Cognitive and Clinical Neurosciences, School of Psychological Sciences, Monash University, Melbourne, Australia
| | - Shakuntla Gondalia
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Masoumeh Tangestani Fard
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Andrew Pipingas
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
| | - Con Stough
- Centre for Human Psychopharmacology, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria, Melbourne, Australia
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Teskey G, Abrahem R, Cao R, Gyurjian K, Islamoglu H, Lucero M, Martinez A, Paredes E, Salaiz O, Robinson B, Venketaraman V. Glutathione as a Marker for Human Disease. Adv Clin Chem 2018; 87:141-159. [PMID: 30342710 DOI: 10.1016/bs.acc.2018.07.004] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Glutathione (GSH), often referred to as "the master antioxidant," participates not only in antioxidant defense systems, but many metabolic processes, and therefore its role cannot be overstated. GSH deficiency causes cellular risk for oxidative damage and thus as expected, GSH imbalance is observed in a wide range of pathological conditions including tuberculosis (TB), HIV, diabetes, cancer, and aging. Consequently, it is not surprising that GSH has attracted the attention of biological researchers and pharmacologists alike as a possible target for medical intervention. Here, we discuss the role GSH plays amongst these pathological conditions to illuminate how it can be used as a marker for human disease.
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Affiliation(s)
- Garrett Teskey
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Rachel Abrahem
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Ruoqiong Cao
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, United States; College of life Sciences, Hebei University, Baoding, China
| | - Karo Gyurjian
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, United States
| | - Hicret Islamoglu
- Department of Biological Sciences, California State Polytechnic University, Pomona, CA, United States
| | - Mariana Lucero
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Andrew Martinez
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Erik Paredes
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States
| | - Oscar Salaiz
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, United States
| | - Brittanie Robinson
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, United States
| | - Vishwanath Venketaraman
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA, United States; Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, United States
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6
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Glutathione in the human brain: Review of its roles and measurement by magnetic resonance spectroscopy. Anal Biochem 2016; 529:127-143. [PMID: 28034792 DOI: 10.1016/j.ab.2016.12.022] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 12/21/2016] [Accepted: 12/23/2016] [Indexed: 12/12/2022]
Abstract
We review the transport, synthesis and catabolism of glutathione in the brain as well as its compartmentation and biochemistry in different brain cells. The major reactions involving glutathione are reviewed and the factors limiting its availability in brain cells are discussed. We also describe and critique current methods for measuring glutathione in the human brain using magnetic resonance spectroscopy, and review the literature on glutathione measurements in healthy brains and in neurological, psychiatric, neurodegenerative and neurodevelopmental conditions In summary: Healthy human brain glutathione concentration is ∼1-2 mM, but it varies by brain region, with evidence of gender differences and age effects; in neurological disease glutathione appears reduced in multiple sclerosis, motor neurone disease and epilepsy, while being increased in meningiomas; in psychiatric disease the picture is complex and confounded by methodological differences, regional effects, length of disease and drug-treatment. Both increases and decreases in glutathione have been reported in depression and schizophrenia. In Alzheimer's disease and mild cognitive impairment there is evidence for a decrease in glutathione compared to age-matched healthy controls. Improved methods to measure glutathione in vivo will provide better precision in glutathione determination and help resolve the complex biochemistry of this molecule in health and disease.
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Erkenekli K, Sanhal CY, Yucel A, Bicer CK, Erel O, Uygur D. Thiol/disulfide homeostasis in patients with idiopathic recurrent pregnancy loss assessed by a novel assay: Report of a preliminary study. J Obstet Gynaecol Res 2015; 42:136-41. [DOI: 10.1111/jog.12860] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Revised: 07/29/2015] [Accepted: 08/16/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Kudret Erkenekli
- Department of Perinatology; Dr. Zekai Tahir Burak Women's Health Care, Education and Research Hospital; Ankara Turkey
| | - Cem Yasar Sanhal
- Department of Perinatology; Dr. Zekai Tahir Burak Women's Health Care, Education and Research Hospital; Ankara Turkey
| | - Aykan Yucel
- Department of Perinatology; Dr. Zekai Tahir Burak Women's Health Care, Education and Research Hospital; Ankara Turkey
| | - Cemile Koca Bicer
- Department of Clinical Biochemistry, Faculty of Medicine; Yildirim Beyazit University; Ankara Turkey
| | - Ozcan Erel
- Department of Clinical Biochemistry, Faculty of Medicine; Yildirim Beyazit University; Ankara Turkey
| | - Dilek Uygur
- Department of Perinatology; Dr. Zekai Tahir Burak Women's Health Care, Education and Research Hospital; Ankara Turkey
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Toncelli A, Noeske R, Cosottini M, Costagli M, Domenici V, Tiberi G, Tosetti M. STEAM-MiTiS: An MR spectroscopy method for the detection of scalar-coupled metabolites and its application to glutamate at 7 T. Magn Reson Med 2014; 74:1515-22. [DOI: 10.1002/mrm.25556] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 10/28/2014] [Accepted: 11/09/2014] [Indexed: 11/07/2022]
Affiliation(s)
| | - Ralph Noeske
- MR Applications and Workflow Development; GE Healthcare; Berlin Germany
| | - Mirco Cosottini
- Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia; University of Pisa; Pisa Italy
- Fondazione IMAGO7; Pisa Italy
| | - Mauro Costagli
- Fondazione IMAGO7; Pisa Italy
- Laboratorio di Fisica Medica e Biotecnologie per la Risonanza Magnetica IRCCS Fondazione Stella Maris; Pisa Italy
| | - Valentina Domenici
- Dipartimento di Chimica e Chimica Industriale; University of Pisa; Pisa Italy
| | - Gianluigi Tiberi
- Fondazione IMAGO7; Pisa Italy
- Laboratorio di Fisica Medica e Biotecnologie per la Risonanza Magnetica IRCCS Fondazione Stella Maris; Pisa Italy
| | - Michela Tosetti
- Fondazione IMAGO7; Pisa Italy
- Laboratorio di Fisica Medica e Biotecnologie per la Risonanza Magnetica IRCCS Fondazione Stella Maris; Pisa Italy
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Poels EMP, Kegeles LS, Kantrowitz JT, Slifstein M, Javitt DC, Lieberman JA, Abi-Dargham A, Girgis RR. Imaging glutamate in schizophrenia: review of findings and implications for drug discovery. Mol Psychiatry 2014; 19:20-9. [PMID: 24166406 DOI: 10.1038/mp.2013.136] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 08/25/2013] [Accepted: 09/09/2013] [Indexed: 12/11/2022]
Abstract
Currently, all treatments for schizophrenia (SCZ) function primarily by blocking D(2)-type dopamine receptors. Given the limitations of these medications, substantial efforts have been made to identify alternative neurochemical targets for treatment development in SCZ. One such target is brain glutamate. The objective of this article is to review and synthesize the proton magnetic resonance spectroscopy ((1)H MRS) and positron emission tomography (PET)/single-photon emission computed tomography (SPECT) investigations that have examined glutamatergic indices in SCZ, including those of modulatory compounds such as glutathione (GSH) and glycine, as well as data from ketamine challenge studies. The reviewed (1)H MRS and PET/SPECT studies support the theory of hypofunction of the N-methyl-D-aspartate receptor (NMDAR) in SCZ, as well as the convergence between the dopamine and glutamate models of SCZ. We also review several advances in MRS and PET technologies that have opened the door for new opportunities to investigate the glutamate system in SCZ and discuss some ways in which these imaging tools can be used to facilitate a greater understanding of the glutamate system in SCZ and the successful and efficient development of new glutamate-based treatments for SCZ.
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Affiliation(s)
- E M P Poels
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
| | - L S Kegeles
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
| | - J T Kantrowitz
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
| | - M Slifstein
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
| | - D C Javitt
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
| | - J A Lieberman
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
| | - A Abi-Dargham
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA [3] Department of Radiology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - R R Girgis
- 1] Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA [2] New York State Psychiatric Institute, New York, NY, USA
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Choi IY, Lee P. Doubly selective multiple quantum chemical shift imaging and T(1) relaxation time measurement of glutathione (GSH) in the human brain in vivo. NMR IN BIOMEDICINE 2013; 26:28-34. [PMID: 22730142 PMCID: PMC3465620 DOI: 10.1002/nbm.2815] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2011] [Revised: 04/11/2012] [Accepted: 04/13/2012] [Indexed: 05/06/2023]
Abstract
Mapping of a major antioxidant, glutathione (GSH), was achieved in the human brain in vivo using a doubly-selective multiple quantum filtering based chemical shift imaging (CSI) of GSH at 3 T. Both in vivo and phantom tests in CSI and single voxel measurements were consistent with excellent suppression of overlapping signals from creatine, γ-Amino butyric acid (GABA) and macromolecules. GSH concentration in the fronto-parietal region was 1.20 ± 0.16 µmol/g (mean ± SD, n = 7). The longitudinal relaxation time (T(1) ) of GSH in the human brain was 397 ± 44 ms (mean ± SD, n = 5), which was substantially shorter than that of other metabolites. This GSH-CSI method permits us to address regional differences of GSH in the human brain under conditions where oxidative stress has been implicated, including multiple sclerosis, aging and neurodegenerative diseases.
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Affiliation(s)
- In-Young Choi
- Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, KS 66160, USA.
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11
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Kim H, Thompson RB, Allen PS. Enhancement of spectral editing efficacy of multiple quantum filters in in vivo proton magnetic resonance spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 223:90-97. [PMID: 22975239 DOI: 10.1016/j.jmr.2012.07.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 07/12/2012] [Accepted: 07/24/2012] [Indexed: 06/01/2023]
Abstract
The performance of multiple quantum filters (MQFs) can be disappointing when the background signal also arises from coupled spins. Moreover, at 3.0 T and even higher fields the majority of the spin systems of key brain metabolites fall into the strong-coupling regime. In this manuscript we address comprehensively, the importance of the phase of the multiple quantum coherence-generating pulse (MQ-pulse) in the design of MQFs, using both product operator and numerical analysis, in both zero and double quantum filter designs. The theoretical analyses were experimentally validated with the examples of myo-inositol editing and the separation of glutamate from glutamine. The results demonstrate that the phase of the MQ-pulse per se provides an additional spectral discrimination mechanism based on the degree of coupling beyond the conventional level-of-coherence approach of MQFs. To obtain the best spectral discrimination of strongly-coupled spin systems, therefore, the phase of the MQ-pulse must be included in the portfolio of the sequence parameters to be optimized.
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Affiliation(s)
- Hyeonjin Kim
- Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea.
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12
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Wei L, Hong S, Yoon Y, Hwang SN, Park JC, Zhang Z, Olson JJ, Hu XP, Shim H. Early prediction of response to Vorinostat in an orthotopic rat glioma model. NMR IN BIOMEDICINE 2012; 25:1104-11. [PMID: 22302519 PMCID: PMC3356508 DOI: 10.1002/nbm.2776] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 12/13/2011] [Accepted: 12/13/2011] [Indexed: 05/22/2023]
Abstract
Glioblastoma is the most common primary brain tumor and is uniformly fatal despite aggressive surgical and adjuvant therapy. As survival is short, it is critical to determine the value of therapy early on in treatment. Improved early predictive assessment would allow neuro-oncologists to personalize and adjust or change treatment sooner to maximize the use of efficacious therapy. During carcinogenesis, tumor suppressor genes can be silenced by aberrant histone deacetylation. This epigenetic modification has become an important target for tumor therapy. Suberoylanilide hydroxamic acid (SAHA, Vorinostat, Zolinza) is an orally active, potent inhibitor of histone deacetylase (HDAC) activity. A major shortcoming of the use of HDAC inhibitors in the treatment of patients with brain tumors is the lack of reliable biomarkers to predict and determine response. Histological evaluation may reflect tumor viability following treatment, but is an invasive procedure and impractical for glioblastoma. Another problem is that response to SAHA therapy is associated with tumor redifferentiation and cytostasis rather than tumor size reduction, thus limiting the use of traditional imaging methods. A noninvasive method to assess drug delivery and efficacy is needed. Here, we investigated whether changes in (1)H MRS metabolites could render reliable biomarkers for an early response to SAHA treatment in an orthotopic animal model for glioma. Untreated tumors exhibited significantly elevated alanine and lactate levels and reduced inositol, N-acetylaspartate and creatine levels, typical changes reported in glioblastoma relative to normal brain tissues. The (1)H MRS-detectable metabolites of SAHA-treated tumors were restored to those of normal-like brain tissues. In addition, reduced inositol and N-acetylaspartate were found to be potential biomarkers for mood alteration and depression, which may also be alleviated with SAHA treatment. Our study suggests that (1)H MRS can provide reliable metabolic biomarkers at the earliest stage of SAHA treatment to predict the therapeutic response.
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Affiliation(s)
- Li Wei
- Department of Biomedical Engineering, Emory University, Atlanta, Georgia 30322, USA
| | - Samuel Hong
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, USA
| | - Younghyoun Yoon
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, USA
| | - Scott N. Hwang
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, USA
| | - Jaekeun C. Park
- Department of Biomedical Engineering, Emory University, Atlanta, Georgia 30322, USA
| | - Zhaobin Zhang
- Department of Neurosurgery, Emory University, Atlanta, Georgia 30322, USA
| | - Jeffrey J. Olson
- Department of Neurosurgery, Emory University, Atlanta, Georgia 30322, USA
| | - Xiaoping P. Hu
- Department of Biomedical Engineering, Emory University, Atlanta, Georgia 30322, USA
| | - Hyunsuk Shim
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, USA
- Winship Cancer Institute, Emory University, Atlanta, Georgia 30322, USA
- Correspondence to: H. Shim, Department of Radiology and Imaging Sciences, Winship Cancer Institute, Emory University, 1701 Uppergate Drive, C5018, Atlanta, GA 30322, Tel: 404-778-4564, Fax: 404-712-5813,
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Park Y, Zhao T, Miller NG, Kim SB, Accardi CJ, Ziegler TR, Hu X, Jones DP. Sulfur amino acid-free diet results in increased glutamate in human midbrain: a pilot magnetic resonance spectroscopic study. Nutrition 2011; 28:235-41. [PMID: 21917421 DOI: 10.1016/j.nut.2011.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 05/01/2011] [Indexed: 01/08/2023]
Abstract
OBJECTIVE This pilot study was designed to determine if metabolic effects in different brain regions (left and right parietal lobes, midbrain) caused by 3 d of food consumption without methionine or cysteine could be detected by proton magnetic resonance spectroscopy. METHODS Healthy individuals 18 to 36 y old (n = 8) were studied by magnetic resonance spectroscopy after receiving a diet with adequate sulfur amino acids (SAAs) or with zero SAA for 3 d. Pulse sequences were used to selectively measure glutathione (GSH), and linear combination modeling of spectra was used to measure other high-abundance brain metabolites and expressed relative to creatine (Cr). RESULTS Although dietary SAAs are required to maintain GSH, the 3-d SAA insufficiency resulted in no significant change in GSH/Cr in the three brain regions. Principal component analysis of 16 metabolites measured by linear combination modeling showed that the metabolic pattern in the midbrain, but not in the parietal lobes, was distinguished according to the dietary SAAs. Multivariate statistical analysis showed that the major discriminating factors were signals of glutamate/Cr, (glutamate + glutamine)/Cr, and myoinositol/Cr. Correlation analyses between midbrain metabolites and GSH-related metabolites in plasma showed that midbrain glutamate/Cr had an inverse correlation with plasma cystine. CONCLUSION The data show that magnetic resonance spectroscopy is a non-invasive tool suitable for nutritional assessment and suggest that nutritional imbalance caused by 3 d of SAA-free food more selectively affects the midbrain than the parietal lobes.
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Affiliation(s)
- Youngja Park
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, Atlanta, Georgia, USA
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Choi C, Dimitrov IE, Douglas D, Patel A, Kaiser LG, Amezcua CA, Maher EA. Improvement of resolution for brain coupled metabolites by optimized (1)H MRS at 7T. NMR IN BIOMEDICINE 2010; 23:1044-1052. [PMID: 20963800 DOI: 10.1002/nbm.1529] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Resolution enhancement for glutamate (Glu), glutamine (Gln) and glutathione (GSH) in the human brain by TE-optimized point-resolved spectroscopy (PRESS) at 7 T is reported. Sub-TE dependences of the multiplets of Glu, Gln, GSH, γ-aminobutyric acid (GABA) and N-acetylaspartate (NAA) at 2.2-2.6 ppm were investigated with density matrix simulations, incorporating three-dimensional volume localization. The numerical simulations indicated that the C4-proton multiplets can be completely separated with (TE(1), TE(2)) = (37, 63) ms, as a result of a narrowing of the multiplets and suppression of the NAA 2.5 ppm signal. Phantom experiments reproduced the signal yield and lineshape from simulations within experimental errors. In vivo tests of optimized PRESS were conducted on the prefrontal cortex of six healthy volunteers. In spectral fitting by LCModel, Cramér-Rao lower bounds (CRLBs) of Glu, Gln and GSH were 2 ± 1, 5 ± 1 and 6 ± 2 (mean ± SD), respectively. To evaluate the performance of the optimized PRESS method under identical experimental conditions, stimulated-echo spectra were acquired with (TE, TM) = (14, 37) and (74, 68) ms. The CRLB of Glu was similar between PRESS and short-TE stimulated-echo acquisition mode (STEAM), but the CRLBs of Gln and GSH were lower in PRESS than in both STEAM acquisitions.
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Affiliation(s)
- Changho Choi
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Choi IY, Lee SP, Denney DR, Lynch SG. Lower levels of glutathione in the brains of secondary progressive multiple sclerosis patients measured by 1H magnetic resonance chemical shift imaging at 3 T. Mult Scler 2010; 17:289-96. [PMID: 20921235 DOI: 10.1177/1352458510384010] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Disability levels for patients with secondary progressive multiple sclerosis (SPMS) often worsen despite a stable MRI T(2) lesion burden. The presence of oxidative stress in the absence of measurable inflammation could help explain this phenomenon. In this study, the assessment of an in vivo marker of oxidative stress, cerebral glutathione (GSH), using magnetic resonance chemical shift imaging (CSI) is described, and GSH levels were compared in patients with SPMS and healthy controls. OBJECTIVE To assess whether GSH, a key antioxidant in the brain, is lower in the SPMS patients compared to matched controls. METHODS Seventeen patients with SPMS (Expanded Disability Status Scale=4.0-7.0; length of MS diagnosis=19.4 ± 7 years) and 17 age- and gender-matched healthy controls were studied. GSH levels were measured in the fronto-parietal regions of the brain using a specially designed magnetic resonance spectroscopy technique, CSI of GSH, at 3T. RESULTS The levels of GSH were lower for SPMS patients than for controls, the largest reduction (18.5%) being in the frontal region (p=0.001). CONCLUSION The lower GSH levels in these patients indicate the presence of oxidative stress in SPMS. This process could be at least partially responsible for ongoing functional decline in SPMS.
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Affiliation(s)
- I-Y Choi
- Hoglund Brain Imaging Center, Department of Neurology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
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Lin Y, Gu T, Chen Z, Kennedy S, Jacob M, Zhong J. High-resolution MRS in the presence of field inhomogeneity via intermolecular double-quantum coherences on a 3-T whole-body scanner. Magn Reson Med 2010; 63:303-11. [PMID: 20099324 DOI: 10.1002/mrm.22224] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Signals from intermolecular double-quantum coherences (iDQCs) have been shown to be insensitive to macroscopic field inhomogeneities and thus enable acquisition of high- resolution MR spectroscopy in the presence of large inhomogeneous fields. In this paper, localized iDQC (1)H spectroscopy on a whole-body 3-T MR scanner is reported. Experiments with a brain metabolite phantom were performed to quantify characteristics of the iDQC signal under different conditions. The feasibility of in vivo iDQC high-resolution MR spectroscopy in the presence of large intrinsic and external field inhomogeneity (in the order of hundreds of hertz) was demonstrated in the whole cerebellum of normal volunteers in a scan time of about 6.5 min. Major metabolite peaks were well resolved in the reconstructed one-dimensional spectra projected from two-dimensional iDQC acquisitions. Investigations on metabolite ratios, signal-to-noise ratio, and line width were performed and compared with results obtained with conventional point-resolved spectroscopy/MR spectroscopy in homogeneous fields. Metabolite ratios from iDQC results showed excellent consistency under different in vitro and in vivo conditions, and they were similar to those from point-resolved spectroscopy with small voxel sizes in homogeneous fields. MR spectroscopy with iDQCs can be applied potentially for quantification of gross metabolite changes due to diseases in large brain volumes with high field inhomogeneity.
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Affiliation(s)
- Yanqin Lin
- Department of Imaging Sciences, University of Rochester, Rochester, New York 14642-8648, USA
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Jones DP, Liang Y. Measuring the poise of thiol/disulfide couples in vivo. Free Radic Biol Med 2009; 47:1329-38. [PMID: 19715755 PMCID: PMC2774737 DOI: 10.1016/j.freeradbiomed.2009.08.021] [Citation(s) in RCA: 235] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 08/13/2009] [Accepted: 08/16/2009] [Indexed: 02/07/2023]
Abstract
The reduction potentials (E(h)) for the redox couples GSH/GSSG and cysteine/cystine (Cys/CySS) in plasma are useful indicators of systemic oxidative stress and other medically relevant physiological states. This article describes a sensitive method for determining plasma levels of GSH, GSSG, Cys, and CySS used to calculate the in vivo E(h) values. The method uses iodoacetate to alkylate free thiols, derivatization with dansyl chloride to fluorescently tag amino groups, and HPLC and fluorescence to separate, detect, and quantify the molecules. Benefits of the method, such as sensitivity and dynamic range, are described, as are caveats, such as the importance of preventing red blood cell hemolysis and limitations in quantification of GSSG. General principles of redox chemistry and previous studies showing that the compounds are more oxidized than predicted from their standard reduction potentials are reviewed. The calculated in vivo E(h) is a convenient and informative way of summarizing the redox environment of plasma and is also useful for studies of cerebrospinal fluid, lymph, bronchoalveolar lavage fluid, human biopsies, and a broad range of in vitro cell culture conditions.
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Affiliation(s)
- Dean P Jones
- Clinical Biomarkers Laboratory, Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Determination of glutathione and glutathione disulfide in biological samples: An in-depth review. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:3331-46. [DOI: 10.1016/j.jchromb.2009.06.016] [Citation(s) in RCA: 197] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Revised: 06/02/2009] [Accepted: 06/10/2009] [Indexed: 12/13/2022]
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An L, Zhang Y, Thomasson DM, Latour LL, Baker EH, Shen J, Warach S. Measurement of glutathione in normal volunteers and stroke patients at 3T using J-difference spectroscopy with minimized subtraction errors. J Magn Reson Imaging 2009; 30:263-70. [PMID: 19629994 DOI: 10.1002/jmri.21832] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To develop and optimize a (1)H magnetic resonance spectroscopy (MRS) method for measuring brain glutathione (GSH) levels. MATERIALS AND METHODS Phantom experiments and density operator simulations were performed to determine the optimal TE for measuring GSH at 3T using J-difference spectral editing. In vivo data collected from 11 normal volunteers (43 measurements) and five stroke patients (10 measurements) were processed using a new spectral alignment method (adaptive spectral registration). RESULTS In phantom experiments and density operator simulations where relaxation effects were ignored, close to maximum GSH signal (2.95 ppm) was obtained at TE approximately 131 msec with minimum N-acetyl-aspartate (NAA) signal interference. Using adaptive spectral registration, GSH levels in healthy volunteers were found to be 1.20 +/- 0.14 mM (mean +/- standard deviation [SD]). GSH levels in stroke patients were found to be 1.19 +/- 0.24 mM in lesion and 1.25 +/- 0.19 mM in contralateral normal tissue. In comparison, the SDs were significantly larger when only the NAA singlet (2.01 ppm) was used as a navigator for spectral alignment. CONCLUSION Spectral editing using J-differences is a reliable method for measuring GSH levels in volunteers and stroke patients.
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Affiliation(s)
- Li An
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20814, USA.
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Choi C, Zhao C, Dimitrov I, Douglas D, Coupland NJ, Kalra S, Hawesa H, Davis J. Measurement of glutathione in human brain at 3T using an improved double quantum filter in vivo. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2009; 198:160-166. [PMID: 19261496 PMCID: PMC2921904 DOI: 10.1016/j.jmr.2009.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 02/05/2009] [Accepted: 02/05/2009] [Indexed: 05/27/2023]
Abstract
A single voxel proton NMR double quantum filter (DQF) for measurement of glutathione (GSH) in human brain at 3T is reported. Yield enhancement for the CH(2) resonances of the cysteine moiety at 2.95ppm has been achieved by means of dual encoding. After the preparation of double quantum and zero quantum coherences (DQC and ZQC) at equal magnitude, the first DQC encoding was followed by interchange of DQC and ZQC, and another DQC encoding. The multi-quantum coherences were fully utilized to generate a GSH target signal at approximately 2.95ppm. The optimal echo time and the editing efficiency were obtained with numerical analysis of the filtering performance and phantom measurements. The dual-DQC encoding method provided GSH yield greater by a factor of 2.1 than single-DQC encoding for identical slice-selective RF pulses in phantom tests. Using the phantom relaxation times and the ratio of edited GSH to N-acetylaspartate (NAA) 2.0-ppm peak areas, the concentration of GSH in the medial parietal cortex of the healthy human brain in vivo was estimated to be 1.0+/-0.3mM (mean+/-SD, n=7), with reference to NAA at 10mM.
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Affiliation(s)
- Changho Choi
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA.
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Jones DP. Radical-free biology of oxidative stress. Am J Physiol Cell Physiol 2008; 295:C849-68. [PMID: 18684987 PMCID: PMC2575825 DOI: 10.1152/ajpcell.00283.2008] [Citation(s) in RCA: 783] [Impact Index Per Article: 48.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2008] [Accepted: 07/31/2008] [Indexed: 12/12/2022]
Abstract
Free radical-induced macromolecular damage has been studied extensively as a mechanism of oxidative stress, but large-scale intervention trials with free radical scavenging antioxidant supplements show little benefit in humans. The present review summarizes data supporting a complementary hypothesis for oxidative stress in disease that can occur without free radicals. This hypothesis, which is termed the "redox hypothesis," is that oxidative stress occurs as a consequence of disruption of thiol redox circuits, which normally function in cell signaling and physiological regulation. The redox states of thiol systems are sensitive to two-electron oxidants and controlled by the thioredoxins (Trx), glutathione (GSH), and cysteine (Cys). Trx and GSH systems are maintained under stable, but nonequilibrium conditions, due to a continuous oxidation of cell thiols at a rate of about 0.5% of the total thiol pool per minute. Redox-sensitive thiols are critical for signal transduction (e.g., H-Ras, PTP-1B), transcription factor binding to DNA (e.g., Nrf-2, nuclear factor-kappaB), receptor activation (e.g., alphaIIbbeta3 integrin in platelet activation), and other processes. Nonradical oxidants, including peroxides, aldehydes, quinones, and epoxides, are generated enzymatically from both endogenous and exogenous precursors and do not require free radicals as intermediates to oxidize or modify these thiols. Because of the nonequilibrium conditions in the thiol pathways, aberrant generation of nonradical oxidants at rates comparable to normal oxidation may be sufficient to disrupt function. Considerable opportunity exists to elucidate specific thiol control pathways and develop interventional strategies to restore normal redox control and protect against oxidative stress in aging and age-related disease.
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Affiliation(s)
- Dean P Jones
- Division of Pulmonary, Allergy and Critical Care Medicine, Clinical Biomarkers Laboratory, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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Yahya A, Gino Fallone B. Incorporating homonuclear polarization transfer into PRESS for proton spectral editing: illustration with lactate and glutathione. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2007; 188:111-21. [PMID: 17638584 DOI: 10.1016/j.jmr.2007.06.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Revised: 06/19/2007] [Accepted: 06/19/2007] [Indexed: 05/16/2023]
Abstract
A proton spectral editing pulse sequence for the detection of metabolites with spin systems that involve weak coupling is presented. The sequence is based on homonuclear polarization transfer incorporated into the standard PRESS (Point RESolved Spectroscopy) sequence, which is a volume-selective double spin echo method, to enable spatial localization. All peaks in the region of interest are initially suppressed whether they are peaks from the target metabolite or from contaminating background. The target signal is then restored by polarization transfer from a proton that has a resonance outside the suppressed region and to which the target spins are weakly coupled. This is achieved by the application of a 90 degrees hard pulse with phase orthogonal to that of the PRESS excitation pulse at the location of the first echo in PRESS and by optimizing the two PRESS timings, TE(1) and TE(2), for most efficient yield. Background signal not coupled to any protons outside the initially saturated region remains suppressed. The advantage of this sequence compared to multiple quantum filters is that signal from singlet peaks outside the suppressed area are preserved and can thus be used as a reference. The efficacy of the sequence was verified experimentally on phantom solutions of lactate and glutathione at 3.0 T. For the AX(3) spin system of lactate, the sequence timings were optimized by product operator calculations whereas for the ABX spin system of the cysteinyl group of glutathione numerical calculations were performed for sequence timing optimization.
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Affiliation(s)
- Atiyah Yahya
- Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta, Canada T6G 1Z2
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