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Strekalova T, Radford-Smith D, Dunstan IK, Gorlova A, Svirin E, Sheveleva E, Burova A, Morozov S, Lyundup A, Berger G, Anthony DC, Walitza S. Omega-3 alleviates behavioral and molecular changes in a mouse model of stress-induced juvenile depression. Neurobiol Stress 2024; 31:100646. [PMID: 38912378 PMCID: PMC11190747 DOI: 10.1016/j.ynstr.2024.100646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/29/2024] [Accepted: 05/19/2024] [Indexed: 06/25/2024] Open
Abstract
Introduction Depression is increasingly diagnosed in adolescence, necessitating specific prevention and treatment methods. However, there is a lack of animal models mimicking juvenile depression. This study explores a novel model using ultrasound (US) stress in juvenile mice. Methods We employed the US stress model in one-month-old C57/BL6 mice, exposing them to alternating ultrasound frequencies (20-25 kHz and 25-45 kHz) for three weeks. These frequencies correspond to negative and neutral emotional states in rodents and can induce a depressive-like syndrome. Concurrently, mice received either an omega-3 food supplement (FS) containing eicosapentaenoic acid (EPA; 0.55 mg/kg/day) and docosahexaenoic acid (DHA; 0.55 mg/kg/day) or a vehicle. Post-stress, we evaluated anxiety- and depressive-like behaviors, blood corticosterone levels, brain expression of pro-inflammatory cytokines, and conducted metabolome analysis of brain, liver and blood plasma. Results US-exposed mice treated with vehicle exhibited decreased sucrose preference, a sign of anhedonia, a key feature of depression, increased anxiety-like behavior, elevated corticosterone levels, and enhanced TNF and IL-1β gene expression in the brain. In contrast, US-FS mice did not display these changes. Omega-3 supplementation also reduced anxiety-like behavior in non-stressed mice. Metabolomic analysis revealed US-induced changes in brain energy metabolism, with FS increasing brain sphingomyelin. Liver metabolism was affected by both US and FS, while plasma metabolome changes were exclusive to FS. Brain glucose levels correlated positively with activity in anxiety tests. Conclusion Chronic omega-3 intake counteracted depressive- and anxiety-like behaviors in a US model of juvenile depression in mice. These effects likely stem from the anti-inflammatory properties of the supplement, suggesting potential therapeutic applications in juvenile depression.
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Affiliation(s)
- Tatyana Strekalova
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, the Netherlands
- Department of Pharmacology, Oxford University, Oxford, UK
| | | | | | - Anna Gorlova
- Laboratory of Cognitive Dysfunctions, Institute of General Pathology and Pathophysiology, Moscow, Russia
- RUDN University, 6 Miklukho-Maklaya Str, Moscow, Russia
| | - Evgeniy Svirin
- Laboratory of Cognitive Dysfunctions, Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Elisaveta Sheveleva
- Laboratory of Cognitive Dysfunctions, Institute of General Pathology and Pathophysiology, Moscow, Russia
- Department of Normal Physiology, Sechenov Moscow State Medical University, Moscow, Russia
| | - Alisa Burova
- Laboratory of Cognitive Dysfunctions, Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Sergey Morozov
- Laboratory of Cognitive Dysfunctions, Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Aleksey Lyundup
- RUDN University, 6 Miklukho-Maklaya Str, Moscow, Russia
- Endocrinology Research Centre, Dmitry Ulyanov str. 19, Moscow, 117036, Russia
| | - Gregor Berger
- Department of Child and Adolescent Psychiatry and Psychotherapy, University of Zuerich, Zuerich, Switzerland
| | | | - Susanne Walitza
- Department of Child and Adolescent Psychiatry and Psychotherapy, University of Zuerich, Zuerich, Switzerland
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Chowdhury GMI, Behar KL, Mason GF, Rothman DL, de Graaf RA. Measurement of neuro-energetics and neurotransmission in the rat olfactory bulb using 1H and 1H-[ 13C] NMR spectroscopy. NMR IN BIOMEDICINE 2024; 37:e4957. [PMID: 37088548 PMCID: PMC10590826 DOI: 10.1002/nbm.4957] [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: 01/13/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 05/03/2023]
Abstract
The olfactory bulb (OB) plays a fundamental role in the sense of smell and has been implicated in several pathologies, including Alzheimer's disease. Despite its importance, high metabolic activity and unique laminar architecture, the OB is not frequently studied using MRS methods, likely due to the small size and challenging location. Here we present a detailed metabolic characterization of OB metabolism, in terms of both static metabolite concentrations using 1H MRS and metabolic fluxes associated with neuro-energetics and neurotransmission by tracing the dynamic 13C flow from intravenously administered [1,6-13C2]-glucose, [2-13C]-glucose and [2-13C]-acetate to downstream metabolites, including [4-13C]-glutamate, [4-13C]-glutamine and [2-13C]-GABA. The unique laminar architecture and associated metabolism of the OB, distinctly different from that of the cerebral cortex, is characterized by elevated GABA and glutamine levels, as well as increased GABAergic and astroglial energy metabolism and neurotransmission. The results show that, despite the technical challenges, high-quality 1H and 1H-[13C] MR spectra can be obtained from the rat OB in vivo. The derived metabolite concentrations and metabolic rates demonstrate a unique metabolic profile for the OB. The metabolic model provides a solid basis for future OB studies on functional activation or pathological conditions.
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Affiliation(s)
- Golam M. I. Chowdhury
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Kevin L. Behar
- Department of Psychiatry, 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
- Department of Psychiatry, 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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3
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Chen X, Bertho G, Caradeuc C, Giraud N, Lucas-Torres C. Present and future of pure shift NMR in metabolomics. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:654-673. [PMID: 37157858 DOI: 10.1002/mrc.5356] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 04/30/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023]
Abstract
NMR is one of the most powerful techniques for the analysis of biological samples in the field of metabolomics. However, the high complexity of fluids, tissues, or other biological materials taken from living organisms is still a challenge for state-of-the-art pulse sequences, thereby limiting the detection, the identification, and the quantification of metabolites. In this context, the resolution enhancement provided by broadband homonuclear decoupling methods, which allows for simplifying 1 H multiplet patterns into singlets, has placed this so-called pure shift technique as a promising approach to perform metabolic profiling with unparalleled level of detail. In recent years, the many advances achieved in the design of pure shift experiments has paved the way to the analysis of a wide range of biological samples with ultra-high resolution. This review leads the reader from the early days of the main pure shift methods that have been successfully developed over the last decades to address complex samples, to the most recent and promising applications of pure shift NMR to the field of NMR-based metabolomics.
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Affiliation(s)
- Xi Chen
- Université Paris Cité, CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Paris, France
| | - Gildas Bertho
- Université Paris Cité, CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Paris, France
| | - Cédric Caradeuc
- Université Paris Cité, CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Paris, France
| | - Nicolas Giraud
- Université Paris Cité, CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Paris, France
| | - Covadonga Lucas-Torres
- Université Paris Cité, CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Paris, France
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4
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Chen X, Caradeuc C, Montagne A, Baud V, Bertho G, Lucas-Torres C, Giraud N. Absolute Metabolite Quantification Using Pure Shift NMR: Toward Quantitative Metabolic Profiling of Aqueous Biological Samples. Anal Chem 2022; 94:14974-14984. [PMID: 36260070 DOI: 10.1021/acs.analchem.2c02823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Accurate quantification of metabolites by nuclear magnetic resonance (NMR) is of prime importance in the field of health sciences for understanding the metabolic pathways of the investigated system, to address the mechanisms of action of diseases, and improving their diagnosis, treatment, and prognosis. Unfortunately, the absolute quantitative analysis of complex samples is still limited by sensitivity and resolution issues that are intrinsic to this technique. Ultrahigh-resolution pure shift methods have especially shown to be suitable for interpreting mixtures of metabolites in biological samples. Here, we introduce a robust analytical protocol based on the use of a pure shift library of calibration reference spectra to fit the fingerprint of each metabolite of interest and determine its concentration. The approach based on the SAPPHIRE pulse sequence enhanced with a block for solvent suppression has been validated through the results of a series of model mixtures, exhibiting excellent trueness (slope values in the range of 0.93-1.02) and linearity (R2 > 0.996) in a total time (a few hours) that is fully compatible with metabolomics studies. Furthermore, we have successfully applied our method to determine the absolute metabolite concentrations in a lymphoma extracellular medium, which improves metabolomic protocols reported to date by providing a quantitative and highly resolved vision of metabolic processes at play.
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Affiliation(s)
- X Chen
- CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, F-75006Paris, France
| | - C Caradeuc
- CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, F-75006Paris, France
| | - A Montagne
- NF-κB, Différenciation et Cancer, Université Paris Cité, F-75006Paris, France
| | - V Baud
- NF-κB, Différenciation et Cancer, Université Paris Cité, F-75006Paris, France
| | - G Bertho
- CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, F-75006Paris, France
| | - C Lucas-Torres
- CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, F-75006Paris, France
| | - N Giraud
- CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, F-75006Paris, France
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5
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Kumaragamage C, Coppoli A, Brown PB, McIntyre S, Nixon TW, De Feyter HM, Mason GF, de Graaf RA. Short symmetric and highly selective asymmetric first and second order gradient modulated offset independent adiabaticity (GOIA) pulses for applications in clinical MRS and MRSI. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 341:107247. [PMID: 35691241 PMCID: PMC9933141 DOI: 10.1016/j.jmr.2022.107247] [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: 02/19/2022] [Revised: 05/04/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Gradient modulated RF pulses, especially gradient offset independent adiabaticity (GOIA) pulses, are increasingly gaining attention for high field clinical magnetic resonance spectroscopy and spectroscopic imaging (MRS/MRSI) due to the lower peak B1 amplitude and associated power demands achievable relative to its non-modulated adiabatic full passage counterparts. In this work we describe the development of two GOIA RF pulses: 1) A power efficient, 3.0 ms wideband uniform rate with smooth truncation (WURST) modulated RF pulse with 15 kHz bandwidth compatible with a clinically feasible peak B1 amplitude of 0.87 kHz (or 20 µT), and 2) A highly selective asymmetric 6.66 ms RF pulse with 20 kHz bandwidth designed to achieve a single-sided, fractional transition width of only 1.7%. Effects of potential asynchrony between RF and gradient-modulated (GM) waveforms for 3 ms GOIA-WURST RF pulses was evaluated by simulation and experimentally. Results demonstrate that a 20+ µs asynchrony between RF and GM functions substantially degrades inversion performance when using large RF offsets to achieve translation. A projection-based method is presented that allows a quick calibration of RF and GM asynchrony on pre-clinical/clinical MR systems. The asymmetric GOIA pulse was implemented within a multi-pulse OVS sequence to achieve power efficient, highly-selective, and B1 and T1-independent signal suppression for extracranial lipid suppression. The developed GOIA pulses were utilized with linear gradient modulation (X, Y, Z gradient fields), and with second-order-field modulations (Z2, X2Y2 gradient fields) to provide elliptically-shaped regions-of-interest for MRS and MRSI acquisitions. Both described GOIA-RF pulses have substantial clinical value; specifically, the 3.0 ms GOIA-WURST pulse is beneficial to realize short TE sLASER localized proton MRS/MRSI sequences, and the asymmetric GOIA RF pulse has applications in highly selective outer volume signal suppression to allow interrogation of tissue proximal to extracranial lipids with full-intensity.
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Affiliation(s)
- Chathura Kumaragamage
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA.
| | - Anastasia Coppoli
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA
| | - Peter B Brown
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA
| | - Scott McIntyre
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA
| | - Terence W Nixon
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA
| | - Henk M De Feyter
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA
| | - Graeme F Mason
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Biomedical Engineering, Yale University School of Medicine, New Haven, CT, USA
| | - Robin A de Graaf
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT, USA; Department of Biomedical Engineering, Yale University School of Medicine, New Haven, CT, USA
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6
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Berner S, Schmidt AB, Ellermann F, Korchak S, Chekmenev EY, Glöggler S, von Elverfeldt D, Hennig J, Hövener JB. High field parahydrogen induced polarization of succinate and phospholactate. Phys Chem Chem Phys 2021; 23:2320-2330. [PMID: 33449978 DOI: 10.1039/d0cp06281b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The signal enhancement provided by the hyperpolarization of nuclear spins of metabolites is a promising technique for diagnostic magnetic resonance imaging (MRI). To date, most 13C-contrast agents are hyperpolarized utilizing a complex or cost-intensive polarizer. Recently, the in situ parahydrogen-induced 13C hyperpolarization was demonstrated. Hydrogenation, spin order transfer (SOT) by a pulsed NMR sequence, in vivo administration, and detection was achieved within the magnet bore of a 7 Tesla MRI system. So far, the hyperpolarization of the xenobiotic molecule 1-13C-hydroxyethylpropionate (HEP) and the biomolecule 1-13C-succinate (SUC) through the PH-INEPT+ sequence and a SOT scheme proposed by Goldman et al., respectively, was shown. Here, we investigate further the hyperpolarization of SUC at 7 Tesla and study the performance of two additional SOT sequences. Moreover, we present first results of the hyperpolarization at high magnetic field of 1-13C-phospholactate (PLAC), a derivate to obtain the metabolite lactate, employing the PH-INEPT+ sequence. For SUC and PLAC, 13C polarizations of about 1-2% were achieved within seconds and with minimal equipment. Effects that potentially may explain loss of 13C polarization have been identified, i.e. low hydrogenation yield, fast T1/T2 relaxation and the rarely considered 13C isotope labeling effect.
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Affiliation(s)
- Stephan Berner
- Department of Radiology, Medical Physics, Medical Center, University of Freiburg, Faculty of Medicine, Germany.
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7
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Bahadoor A, Brinkmann A, Melanson JE. 13C-Satellite Decoupling Strategies for Improving Accuracy in Quantitative Nuclear Magnetic Resonance. Anal Chem 2021; 93:851-858. [PMID: 33300782 DOI: 10.1021/acs.analchem.0c03428] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quantitative 1H nuclear magnetic resonance (qHNMR) with an appropriate internal standard is a well-established quantitation method for assigning purity to organic molecules. For accurate measurements, the premise of qHNMR relies on the careful selection of integrals, for both the analyte and the standard, in such a way that the selected integrals are free from interferences. The 13C-satellite signals of adjacent integrals, low-level impurities, and tautomer signals are among the common integral interferences that are typically encountered. One of the simplest ways to identify and avoid these interferences is to decouple the 13C-satellites. Two decoupling schemes were explored to illustrate the benefits of 13C-decoupling for qHNMR or qH{13C}NMR: GARP and bilevel adiabatic broadband decoupling. Unwanted sample heating and nuclear Overhauser effect (NOE) enhancements are the two main drawbacks of decoupling schemes. We show that with careful optimization of acquisition parameters and decoupling power, no excessive sample heating occurred during acquisition at 400 MHz. At 900 MHz, only bilevel adiabatic decoupling could be safely implemented. Furthermore, any undesirable NOE enhancements were completely avoided if acquisition was executed with an inverse-gated pulse sequence. We explored and confirmed the benefits of qH{13C}NMR through the quantitation of a diverse set of compounds, namely, small molecules (dimethyl terephthalate and zearalenone), a 13C-labeled compound (13C6-ochratoxin A), and an octapeptide (angiotensin II). Statistical comparisons confirmed that qH{13C}NMR produced comparable data to qHNMR. However, with qH{13C}NMR data providing added clarity about the presence of overlapping 13C-satellites, impurities, and tautomers, it has an edge over qHNMR for accurate measurements.
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Affiliation(s)
- Adilah Bahadoor
- Metrology, National Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Andreas Brinkmann
- Metrology, National Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Jeremy E Melanson
- Metrology, National Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
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Chen YL, He ZG, Wang Q, Xiang HB, Fan L, Xiong J. Specific Patterns of Spinal Metabolite Ratio Underlying α-Me-5-HT-evoked Pruritus Compared with Compound 48/80 Based on Proton Nuclear Magnetic Resonance Spectroscopy. Curr Med Sci 2020; 40:761-766. [PMID: 32862388 DOI: 10.1007/s11596-020-2233-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 06/12/2020] [Indexed: 01/03/2023]
Abstract
Mechanisms of pruritus are implicated in the dysregulation of the metabolites in the spinal cord. We investigated pruritus behavioral testing in three groups of young adult male C57Bl/6 mice, including one group treated with normal saline, while the other groups intradermally injected with α-Me-5-HT (histamine-independent pruritogen), compound 48/80 (histamine-dependent pruritogen) at the nape skin of the neck, respectively. Proton nuclear magnetic resonance spectroscopy (MRS) was used to compare spinal metabolites from the vertebral cervical among three groups, and to study the association of spinal metabolite ratio and pruritus intensity. The MRS-measured N-acetylaspartate-to-myoinositol ratio (NAA/Ins) was significantly correlated with the number of scratches between normal saline group and 48/80 group or α-Me-5-HT group (both P<0.0001), indicating that NAA/Ins may be a robust surrogate marker of histamine-independent/dependent pruritogen. There was significant difference in Glu/Ins between normal saline group and 48/80 group (P=0.017), indicating that Glu/Ins may be a surrogate marker of histamine-dependent pruritogen, while GABA/Ins was highly significantly different between normal saline group and α-Me-5-HT group (P=0.008), suggesting that GABA/Ins may be a surrogate marker of histamine-independent pruritogen. MRS may reflect the extent of pruritus intensity elicited by α-Me-5-HT and compound 48/80 with sensitivity similar to the number of scratches, and above potential markers need to be further validated in pre-clinical and clinical treatment trials.
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Affiliation(s)
- Ying-le Chen
- Department of Anesthesiology, the First Affiliated Quanzhou Hospital of Fujian Medical University, Quanzhou, 362000, China
| | - Zhi-Gang He
- Emergency Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qian Wang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hong-Bing Xiang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Li Fan
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
| | - Jun Xiong
- Hepatobiliary Surgery Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
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Dong JW, Li XJ, Cai L, Shi JY, Li YF, Yang C, Li ZJ. Simultaneous determination of alkaloids dicentrine and sinomenine in Stephania epigeae by 1H NMR spectroscopy. J Pharm Biomed Anal 2018; 160:330-335. [PMID: 30114611 DOI: 10.1016/j.jpba.2018.08.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 07/30/2018] [Accepted: 08/04/2018] [Indexed: 02/06/2023]
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Kondo T, Kimura Y, Yamada H, Aoyama Y. Polymeric 1 H MRI Probes for Visualizing Tumor In Vivo. CHEM REC 2017; 17:555-568. [PMID: 28387472 DOI: 10.1002/tcr.201600144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Indexed: 11/09/2022]
Abstract
Magnetic resonance imaging (MRI) has become a prominent non- or low-invasive imaging technique, providing high-resolution, three-dimensional images as well as physiological information about tissues. Low-molecular-weight Gd-MRI contrast agents (CAs), such as Gd-DTPA (DTPA: diethylenetriaminepentaacetic acid), are commonly used in the clinical diagnosis, while macromolecular Gd-MRI CAs have several advantages over low-molecular-weight Gd-MRI CAs, which help minimize the dose of CAs and the risk of side effects. Accordingly, we developed chiral dendrimer Gd-MRI CAs, which showed high r1 values. The association constant values (Ka ) of S-isomeric dendrimer CAs to bovine serum albumin (BSA) were higher than those of R-isomeric dendrimer CAs. Besides, based on a totally new concept, we developed 13 C/15 N-enriched multiple-resonance NMR/MRI probes, which realized highly selective observation of the probes and analysis of metabolic reactions of interest. This account summarizes our recent study on developing both chiral dendrimer Gd-MRI CAs, and self-traceable 13 C/15 N-enriched phosphorylcholine polymer probes for early detection of tumors.
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Affiliation(s)
- Teruyuki Kondo
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 6158510, JAPAN
| | - Yu Kimura
- Research and Educational Unit of Leaders for Integrated Medical Systems, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 6158510, JAPAN
| | - Hisatsugu Yamada
- Field of Bioresource Chemistry and Technology, Graduate School of Bioscience and Bioindustry, Tokushima University, 2-1, Minamijosanjima-cho, Tokushima, 7708506, JAPAN
| | - Yasuhiro Aoyama
- Professor emeritus, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 6158510, JAPAN
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Liu T, He Z, Tian X, Kamal GM, Li Z, Liu Z, Liu H, Xu F, Wang J, Xiang H. Specific patterns of spinal metabolites underlying α-Me-5-HT-evoked pruritus compared with histamine and capsaicin assessed by proton nuclear magnetic resonance spectroscopy. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1222-1230. [PMID: 28344131 DOI: 10.1016/j.bbadis.2017.03.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 03/22/2017] [Accepted: 03/22/2017] [Indexed: 12/29/2022]
Abstract
The mechanism behind itching is not well understood. Proton nuclear magnetic resonance (1H-NMR) spectroscopic analysis of spinal cord extracts provides a quick modality for evaluating the specific metabolic activity of α-Me-5-HT-evoked pruritus mice. In the current study, four groups of young adult male C57Bl/6 mice were investigated; one group treated with saline, while the other groups intradermally injected with α-Me-5-HT (histamine independent pruritogen), histamine (histamine dependent pruritogen) and capsaicin (algogenic substance), respectively. The intradermal microinjection of α-Me-5-HT and histamine resulted in a dramatic increase in the itch behavior. Furthermore, the results of NMR studies of the spinal cord extracts revealed that the metabolites show very different patterns for these different drugs, especially when comparing α-Me-5-HT and capsaicin. All the animals in the groups of α-Me-5-HT and capsaicin were completely separated using the metabolite parameters and principal component analysis. For α-Me-5-HT, the concentrations of glutamate, GABA, glycine and aspartate increased significantly, especially for GABA (increased 17.2%, p=0.008). Furthermore, the concentration of NAA increased, but there was no significant difference (increased 11.3%, p=0.191) compared to capsaicin (decreased 29.1%, p=0.002). Thus the application of magnetic resonance spectroscopy technique, coupled with statistical analysis, could further explain the mechanism behind itching evoked by α-Me-5-HT or other drugs. It can thus improve our understanding of itch pathophysiology and pharmacological therapies which may contribute to itch relief.
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Affiliation(s)
- Taotao Liu
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China; Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Zhigang He
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Xuebi Tian
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Ghulam Mustafa Kamal
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Zhixiao Li
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Zeyuan Liu
- College of Life Science, Wuhan University, Wuhan, Hubei 430076, PR China
| | - Huili Liu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China
| | - Fuqiang Xu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Jie Wang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Hongbing Xiang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China.
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12
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Vinaixa M, Rodríguez MA, Aivio S, Capellades J, Gómez J, Canyellas N, Stracker TH, Yanes O. Positional Enrichment by Proton Analysis (PEPA): A One-Dimensional 1 H-NMR Approach for 13 C Stable Isotope Tracer Studies in Metabolomics. Angew Chem Int Ed Engl 2017; 56:3531-3535. [PMID: 28220994 PMCID: PMC5363230 DOI: 10.1002/anie.201611347] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 01/11/2017] [Indexed: 11/12/2022]
Abstract
A novel metabolomics approach for NMR-based stable isotope tracer studies called PEPA is presented, and its performance validated using human cancer cells. PEPA detects the position of carbon label in isotopically enriched metabolites and quantifies fractional enrichment by indirect determination of 13 C-satellite peaks using 1D-1 H-NMR spectra. In comparison with 13 C-NMR, TOCSY and HSQC, PEPA improves sensitivity, accelerates the elucidation of 13 C positions in labeled metabolites and the quantification of the percentage of stable isotope enrichment. Altogether, PEPA provides a novel framework for extending the high-throughput of 1 H-NMR metabolic profiling to stable isotope tracing in metabolomics, facilitating and complementing the information derived from 2D-NMR experiments and expanding the range of isotopically enriched metabolites detected in cellular extracts.
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Affiliation(s)
- Maria Vinaixa
- Department of Electronic Engineering-Universitat Rovira i VirgiliSpanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)43204ReusSpain
| | - Miguel A. Rodríguez
- Universitat Rovira i VirgiliSpanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)43204ReusSpain
| | - Suvi Aivio
- Institute for Research in Biomedicine (IRB Barcelona)The Barcelona Institute of Science and Technology08028BarcelonaSpain
| | - Jordi Capellades
- Universitat Rovira i VirgiliSpanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)43204ReusSpain
| | - Josep Gómez
- Department of Electronic Engineering-Universitat Rovira i Virgili43007TarragonaSpain
| | - Nicolau Canyellas
- Department of Electronic Engineering-Universitat Rovira i Virgili43007TarragonaSpain
| | - Travis H. Stracker
- Institute for Research in Biomedicine (IRB Barcelona)The Barcelona Institute of Science and Technology08028BarcelonaSpain
| | - Oscar Yanes
- Department of Electronic Engineering-Universitat Rovira i VirgiliSpanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)43204ReusSpain
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13
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Vinaixa M, Rodríguez MA, Aivio S, Capellades J, Gómez J, Canyellas N, Stracker TH, Yanes O. Positional Enrichment by Proton Analysis (PEPA): A One‐Dimensional
1
H‐NMR Approach for
13
C Stable Isotope Tracer Studies in Metabolomics. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Maria Vinaixa
- Department of Electronic Engineering-Universitat Rovira i Virgili Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM) 43204 Reus Spain
| | - Miguel A. Rodríguez
- Universitat Rovira i Virgili Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM) 43204 Reus Spain
| | - Suvi Aivio
- Institute for Research in Biomedicine (IRB Barcelona) The Barcelona Institute of Science and Technology 08028 Barcelona Spain
| | - Jordi Capellades
- Universitat Rovira i Virgili Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM) 43204 Reus Spain
| | - Josep Gómez
- Department of Electronic Engineering- Universitat Rovira i Virgili 43007 Tarragona Spain
| | - Nicolau Canyellas
- Department of Electronic Engineering- Universitat Rovira i Virgili 43007 Tarragona Spain
| | - Travis H. Stracker
- Institute for Research in Biomedicine (IRB Barcelona) The Barcelona Institute of Science and Technology 08028 Barcelona Spain
| | - Oscar Yanes
- Department of Electronic Engineering-Universitat Rovira i Virgili Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM) 43204 Reus Spain
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14
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de Graaf RA, De Feyter HM, Brown PB, Nixon TW, Rothman DL, Behar KL. Detection of cerebral NAD + in humans at 7T. Magn Reson Med 2016; 78:828-835. [PMID: 27670385 DOI: 10.1002/mrm.26465] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 12/31/2022]
Abstract
PURPOSE To develop 1 H-based MR detection of nicotinamide adenine dinucleotide (NAD+ ) in the human brain at 7T and validate the 1 H results with NAD+ detection based on 31 P-MRS. METHODS 1 H-MR detection of NAD+ was achieved with a one-dimensional double-spin-echo method on a slice parallel to the surface coil transceiver. Perturbation of the water resonance was avoided through the use of frequency-selective excitation. 31 P-MR detection of NAD+ was performed with an unlocalized pulse-acquire sequence. RESULTS Both 1 H- and 31 P-MRS allowed the detection of NAD+ signals on every subject in 16 min. Spectral fitting provided an NAD+ concentration of 107 ± 28 μM for 1 H-MRS and 367 ± 78 μM and 312 ± 65 μM for 31 P-MRS when uridine diphosphate glucose (UDPG) was excluded and included, respectively, as an overlapping signal. CONCLUSIONS NAD+ detection by 1 H-MRS is a simple method that comes at the price of reduced NMR visibility. NAD+ detection by 31 P-MRS has near-complete NMR visibility, but it is complicated by spectral overlap with NADH and UDPG. Overall, the 1 H- and 31 P-MR methods both provide exciting opportunities to study NAD+ metabolism on human brain in vivo. © 2016 International Society for Magnetic Resonance in Medicine. Magn Reson Med 78:828-835, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- 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
| | - Henk M De Feyter
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Peter B Brown
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Terence W Nixon
- 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
| | - Kevin L Behar
- Department of Psychiatry, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut, USA
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15
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van Duynhoven JPM, Jacobs DM. Assessment of dietary exposure and effect in humans: The role of NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2016; 96:58-72. [PMID: 27573181 DOI: 10.1016/j.pnmrs.2016.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 03/19/2016] [Accepted: 03/19/2016] [Indexed: 06/06/2023]
Abstract
In human nutritional science progress has always depended strongly on analytical measurements for establishing relationships between diet and health. This field has undergone significant changes as a result of the development of NMR and mass spectrometry methods for large scale detection, identification and quantification of metabolites in body fluids. This has allowed systematic studies of the metabolic fingerprints that biological processes leave behind, and has become the research field of metabolomics. As a metabolic profiling technique, NMR is at its best when its unbiased nature, linearity and reproducibility are exploited in well-controlled nutritional intervention and cross-sectional population screening studies. Although its sensitivity is less good than that of mass spectrometry, NMR has maintained a strong position in metabolomics through implementation of standardisation protocols, hyphenation with mass spectrometry and chromatographic techniques, accurate quantification and spectral deconvolution approaches, and high-throughput automation. Thus, NMR-based metabolomics has contributed uniquely to new insights into dietary exposure, in particular by unravelling the metabolic fates of phytochemicals and the discovery of dietary intake markers. NMR profiling has also contributed to the understanding of the subtle effects of diet on central metabolism and lipoprotein metabolism. In order to hold its ground in nutritional metabolomics, NMR will need to step up its performance in sensitivity and resolution; the most promising routes forward are the analytical use of dynamic nuclear polarisation and developments in microcoil construction and automated fractionation.
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Affiliation(s)
- John P M van Duynhoven
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, 3130AC Vlaardingen, The Netherlands; Laboratory of Biophysics and Wageningen NMR Centre, Wageningen University, Dreijenlaan 3, 6703HA Wageningen, The Netherlands.
| | - Doris M Jacobs
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, 3130AC Vlaardingen, The Netherlands
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16
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Yamada H, Kameda T, Kimura Y, Imai H, Matsuda T, Sando S, Toshimitsu A, Aoyama Y, Kondo T. (13)C/(15)N-Enriched l-Dopa as a Triple-Resonance NMR Probe to Monitor Neurotransmitter Dopamine in the Brain and Liver Extracts of Mice. ChemistryOpen 2016; 5:125-8. [PMID: 27308224 PMCID: PMC4906467 DOI: 10.1002/open.201500196] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Indexed: 12/28/2022] Open
Abstract
In an attempt to monitor μm-level trace constituents, we applied here (1)H-{(13)C-(15)N} triple-resonance nuclear magnetic resonance (NMR) to (13)C/(15)N-enriched l-Dopa as the inevitable precursor of the neurotransmitter dopamine in the brain. The perfect selectivity (to render endogenous components silent) and μm-level sensitivity (700 MHz spectrometer equipped with a cryogenic probe) of triple-resonance allowed the unambiguous and quantitative metabolic and pharmacokinetic analyses of administered l-Dopa/dopamine in the brain and liver of mice. The level of dopamine generated in the brain (within the range 7-76 μm, which covers the typical stimulated level of ∼30 μm) could be clearly monitored ex vivo, but was slightly short of the detection limit of a 7 T MR machine for small animals. This work suggests that μm-level trace constituents are potential targets of ex vivo monitoring as long as they contain N atom(s) and their appropriate (13)C/(15)N-enrichment is synthetically accessible.
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Affiliation(s)
- Hisatsugu Yamada
- Advanced Biomedical Engineering Research UnitCenter for the Promotion of Interdisciplinary Education and ResearchKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
- Department of Life SystemsInstitute of Technology and Science Graduate SchoolTokushima UniversityTokushima770-8506Japan
| | - Tetsuro Kameda
- Department of Energy and Hydrocarbon ChemistryGraduate School of EngineeringKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
| | - Yu Kimura
- Department of Energy and Hydrocarbon ChemistryGraduate School of EngineeringKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
- Research and Educational Unit of Leaders for Integrated Medical SystemCenter for the Promotion of Interdisciplinary Education and ResearchKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
| | - Hirohiko Imai
- Department of Systems ScienceGraduate School of InformaticsKyoto University, Yoshida-honmachi, Sakyo-kuKyoto606-8501Japan
| | - Tetsuya Matsuda
- Department of Systems ScienceGraduate School of InformaticsKyoto University, Yoshida-honmachi, Sakyo-kuKyoto606-8501Japan
| | - Shinsuke Sando
- Department of Chemistry and BiotechnologyThe University of Tokyo, 7-3-1 Hongo, Bunkyo-kuTokyo113-8656Japan
| | - Akio Toshimitsu
- Department of Energy and Hydrocarbon ChemistryGraduate School of EngineeringKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
- Division of Multidisciplinary ChemistryInstitute for Chemical ResearchKyoto University, Gokanosho, UjiKyoto611-0011Japan
| | | | - Teruyuki Kondo
- Advanced Biomedical Engineering Research UnitCenter for the Promotion of Interdisciplinary Education and ResearchKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
- Department of Energy and Hydrocarbon ChemistryGraduate School of EngineeringKyoto University, Katsura, Nishikyo-kuKyoto615-8510Japan
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17
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Patel AB, de Graaf RA, Rothman DL, Behar KL. Effects of γ-Aminobutyric acid transporter 1 inhibition by tiagabine on brain glutamate and γ-Aminobutyric acid metabolism in the anesthetized rat In vivo. J Neurosci Res 2015; 93:1101-8. [PMID: 25663257 DOI: 10.1002/jnr.23548] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 11/14/2014] [Accepted: 12/02/2014] [Indexed: 12/24/2022]
Abstract
γ-Aminobutyric acid (GABA) clearance from the extracellular space after release from neurons involves reuptake into terminals and astrocytes through GABA transporters (GATs). The relative flows through these two pathways for GABA released from neurons remains unclear. This study determines the effect of tiagabine, a selective inhibitor of neuronal GAT-1, on the rates of glutamate (Glu) and GABA metabolism and GABA resynthesis via the GABA-glutamine (Gln) cycle. Halothane-anesthetized rats were administered tiagabine (30 mg/kg, i.p.) and 45 min later received an intravenous infusion of either [1,6-(13)C2]glucose (in vivo) or [2-(13)C]acetate (ex vivo). Nontreated rats served as controls. Metabolites and (13)C enrichments were measured with (1)H-[(13)C]-nuclear magnetic resonance spectroscopy and referenced to their corresponding endpoint values measured in extracts from in situ frozen brain. Metabolic flux estimates of GABAergic and glutamatergic neurons were determined by fitting a metabolic model to the (13)C turnover data measured in vivo during [1,6-(13)C2]glucose infusion. Tiagabine-treated rats were indistinguishable (P > 0.05) from controls in tissue amino acid levels and in (13)C enrichments from [2-(13)C]acetate. Tiagabine reduced average rates of glucose oxidation and neurotransmitter cycling in both glutamatergic neurons (↓18%, CMR(glc(ox)Glu): control, 0.27 ± 0.05 vs. tiagabine, 0.22 ± 0.04 µmol/g/min; ↓11%, V(cyc(Glu-Gln)): control 0.23 ± 0.05 vs. tiagabine 0.21 ± 0.04 µmol/g/min and GABAergic neurons (↓18-25%, CMR(glc(ox)GABA): control 0.09 ± 0.02 vs. tiagabine 0.07 ± 0.03 µmol/g/min; V(cyc(GABA-Gln)): control 0.08 ± 0.02 vs. tiagabine 0.07 ± 0.03 µmol/g/min), but the changes in glutamatergic and GABAergic fluxes were not significant (P > 0.10). The results suggest that any reduction in GABA metabolism by tiagabine might be an indirect response to reduced glutamatergic drive rather than direct compensatory effects.
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Affiliation(s)
- Anant B Patel
- Department of Diagnostic Radiology and the Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Robin A de Graaf
- Department of Diagnostic Radiology and the Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut
| | - Douglas L Rothman
- Department of Diagnostic Radiology and the Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut
| | - Kevin L Behar
- Department of Psychiatry and the Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, Connecticut
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