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Sedlák F, Kvasnička A, Marešová B, Brumarová R, Dobešová D, Dostálová K, Šrámková K, Pehr M, Šácha P, Friedecký D, Konvalinka J. Parallel Metabolomics and Lipidomics of a PSMA/GCPII Deficient Mouse Model Reveal Alteration of NAAG Levels and Brain Lipid Composition. ACS Chem Neurosci 2024; 15:1342-1355. [PMID: 38377674 PMCID: PMC10995945 DOI: 10.1021/acschemneuro.3c00494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 01/10/2024] [Accepted: 02/05/2024] [Indexed: 02/22/2024] Open
Abstract
Glutamate carboxypeptidase II (GCPII, also known as PSMA or FOLH1) is responsible for the cleavage of N-acetyl-aspartyl-glutamate (NAAG) to N-acetyl-aspartate and glutamate in the central nervous system and facilitates the intestinal absorption of folate by processing dietary folyl-poly-γ-glutamate in the small intestine. The physiological function of GCPII in other organs like kidneys is still not known. GCPII inhibitors are neuroprotective in various conditions (e.g., ischemic brain injury) in vivo; however, their utilization as potential drug candidates has not been investigated in regard to not yet known GCPII activities. To explore the GCPII role and possible side effects of GCPII inhibitors, we performed parallel metabolomic and lipidomic analysis of the cerebrospinal fluid (CSF), urine, plasma, and brain tissue of mice with varying degrees of GCPII deficiency (fully deficient in Folh1, -/-; one allele deficient in Folh1, +/-; and wild type, +/+). Multivariate analysis of metabolites showed no significant differences between wild-type and GCPII-deficient mice (except for NAAG), although changes were observed between the sex and age. NAAG levels were statistically significantly increased in the CSF, urine, and plasma of GCPII-deficient mice. However, no difference in NAAG concentrations was found in the whole brain lysate likely because GCPII, as an extracellular enzyme, can affect only extracellular and not intracellular NAAG concentrations. Regarding the lipidome, the most pronounced genotype-linked changes were found in the brain tissue. In brains of GCPII-deficient mice, we observed statistically significant enrichment in phosphatidylcholine-based lipids and reduction of sphingolipids and phosphatidylethanolamine plasmalogens. We hypothesize that the alteration of the NAA-NAAG axis by absent GCPII activity affected myelin composition. In summary, the absence of GCPII and thus similarly its inhibition do not have detrimental effects on metabolism, with just minor changes in the brain lipidome.
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Affiliation(s)
- František Sedlák
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Prague 6 166 10, Czechia
- Institute
of Biochemistry and Experimental Oncology, First Faculty of Medicine, Charles University, Prague 2 110 01, Czechia
- First
Department of Internal Medicine - Hematology, Charles University General Hospital in Prague, Prague 110 01, Czechia
| | - Aleš Kvasnička
- Laboratory
for Inherited Metabolic Disorders, Department of Clinical Biochemistry, University Hospital Olomouc, and Faculty of Medicine
and Dentistry, Palacký University Olomouc, Zdravotníku° 248/7, Olomouc 779 00, Czechia
| | - Barbora Marešová
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Prague 6 166 10, Czechia
- Institute
of Biochemistry and Experimental Oncology, First Faculty of Medicine, Charles University, Prague 2 110 01, Czechia
| | - Radana Brumarová
- Laboratory
for Inherited Metabolic Disorders, Department of Clinical Biochemistry, University Hospital Olomouc, and Faculty of Medicine
and Dentistry, Palacký University Olomouc, Zdravotníku° 248/7, Olomouc 779 00, Czechia
| | - Dana Dobešová
- Laboratory
for Inherited Metabolic Disorders, Department of Clinical Biochemistry, University Hospital Olomouc, and Faculty of Medicine
and Dentistry, Palacký University Olomouc, Zdravotníku° 248/7, Olomouc 779 00, Czechia
| | - Kateřina Dostálová
- Laboratory
for Inherited Metabolic Disorders, Department of Clinical Biochemistry, University Hospital Olomouc, and Faculty of Medicine
and Dentistry, Palacký University Olomouc, Zdravotníku° 248/7, Olomouc 779 00, Czechia
| | - Karolína Šrámková
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Prague 6 166 10, Czechia
| | - Martin Pehr
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Prague 6 166 10, Czechia
- Third
Department of Medicine − Department of Endocrinology and Metabolism
of the first Faculty of Medicine and General University Hospital in
Prague, Charles University, Prague 110 01, Czechia
| | - Pavel Šácha
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Prague 6 166 10, Czechia
| | - David Friedecký
- Laboratory
for Inherited Metabolic Disorders, Department of Clinical Biochemistry, University Hospital Olomouc, and Faculty of Medicine
and Dentistry, Palacký University Olomouc, Zdravotníku° 248/7, Olomouc 779 00, Czechia
| | - Jan Konvalinka
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Prague 6 166 10, Czechia
- Department
of Biochemistry, Faculty of Science, Charles
University, Hlavova 8, Prague 128 00, Czechia
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Chen Y, Yang Y, Zeng X, Feng JL, Oakes K, Zhang X, Cui S. Microfluidic chip interfacing microdialysis and mass spectrometry for in vivo monitoring of nanomedicine pharmacokinetics in real time. J Chromatogr A 2022; 1683:463520. [DOI: 10.1016/j.chroma.2022.463520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 09/16/2022] [Accepted: 09/17/2022] [Indexed: 12/01/2022]
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3
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Naseri Kouzehgarani G, Feldsien T, Engelhard HH, Mirakhur KK, Phipps C, Nimmrich V, Clausznitzer D, Lefebvre DR. Harnessing cerebrospinal fluid circulation for drug delivery to brain tissues. Adv Drug Deliv Rev 2021; 173:20-59. [PMID: 33705875 DOI: 10.1016/j.addr.2021.03.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/10/2021] [Accepted: 03/01/2021] [Indexed: 12/31/2022]
Abstract
Initially thought to be useful only to reach tissues in the immediate vicinity of the CSF circulatory system, CSF circulation is now increasingly viewed as a viable pathway to deliver certain therapeutics deeper into brain tissues. There is emerging evidence that this goal is achievable in the case of large therapeutic proteins, provided conditions are met that are described herein. We show how fluid dynamic modeling helps predict infusion rate and duration to overcome high CSF turnover. We posit that despite model limitations and controversies, fluid dynamic models, pharmacokinetic models, preclinical testing, and a qualitative understanding of the glymphatic system circulation can be used to estimate drug penetration in brain tissues. Lastly, in addition to highlighting landmark scientific and medical literature, we provide practical advice on formulation development, device selection, and pharmacokinetic modeling. Our review of clinical studies suggests a growing interest for intra-CSF delivery, particularly for targeted proteins.
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Li N, Li S, Li T, Yang H, Zhang Y, Zhao Z. Co-Incorporated Mesoporous Carbon Material-Assisted Laser Desorption/Ionization Ion Source as an Online Interface of In Vivo Microdialysis Coupled with Mass Spectrometry. Anal Chem 2020; 92:5482-5491. [PMID: 32181652 DOI: 10.1021/acs.analchem.0c00227] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The combination of microdialysis and mass spectrometry (MS) provides the potential for rapidly monitoring diverse metabolites in vivo. Unfortunately, the high concentration of salt in biological microdialysates hindered the sensitive and online detection of these small molecular compounds. In this study, we synthesized Co-incorporated mesoporous carbon material (Co-NC) and developed a Co-NC-assisted laser desorption/ionization (LDI) ion source as an online interface of in vivo microdialysis coupled with MS for the direct analysis of diverse metabolites in microdialysates. The Co-NC could be used as a matrix for surface-assisted laser desorption/ionization mass spectrometry (SALDI MS) analysis of small molecular compounds, even under high concentration salt conditions. The Co-NC possessed the adsorption ability for small molecular compounds, and it was believed that the adsorption ability of Co-NC might separate the analytes from the salt in microdialysates at a microscopic level, which might facilitate the desorption and ionization of the analytes and finally improved the salt-tolerance ability as a matrix. Furthermore, the Co-NC-assisted LDI ion source as a novel interface of in vivo microdialysis coupled with MS has been applied to the online monitoring of liver metabolites from the CCl4-induced liver injury rat model for the first time.
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Affiliation(s)
- Na Li
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing Mass Spectrum Center, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,Graduate School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shumu Li
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing Mass Spectrum Center, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China
| | - Tuo Li
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing Mass Spectrum Center, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,Graduate School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui Yang
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing Mass Spectrum Center, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,Graduate School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yangyang Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing Mass Spectrum Center, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,Graduate School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhenwen Zhao
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Beijing Mass Spectrum Center, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,Graduate School, University of Chinese Academy of Sciences, Beijing 100049, China
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5
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Rickard JJS, Di-Pietro V, Smith DJ, Davies DJ, Belli A, Oppenheimer PG. Rapid optofluidic detection of biomarkers for traumatic brain injury via surface-enhanced Raman spectroscopy. Nat Biomed Eng 2020; 4:610-623. [DOI: 10.1038/s41551-019-0510-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 12/11/2019] [Indexed: 02/07/2023]
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6
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Zaitsu K, Hayashi Y, Murata T, Yokota K, Ohara T, Kusano M, Tsuchihashi H, Ishikawa T, Ishii A, Ogata K, Tanihata H. In Vivo Real-Time Monitoring System Using Probe Electrospray Ionization/Tandem Mass Spectrometry for Metabolites in Mouse Brain. Anal Chem 2018. [DOI: 10.1021/acs.analchem.7b05291] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Kei Zaitsu
- In Vivo Real-time Omics Laboratory, Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Yumi Hayashi
- In Vivo Real-time Omics Laboratory, Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya, 461-8673, Japan
| | - Tasuku Murata
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Kazumi Yokota
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Tomomi Ohara
- In Vivo Real-time Omics Laboratory, Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Maiko Kusano
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Hitoshi Tsuchihashi
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Tetsuya Ishikawa
- Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya, 461-8673, Japan
| | - Akira Ishii
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Koretsugu Ogata
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Hiroshi Tanihata
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
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Jurdáková H, Górová R, Addová G, Behúlová D, Ostrovský I. The state of treatment approach and diagnostics in Canavan disease with focus on the determination of N-acetylasparic acid. CHEMICAL PAPERS 2017. [DOI: 10.1007/s11696-016-0033-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Ukraintseva YS, Shchegolevskii NV, Korshunov VA, Kucheryanu VG, Ugryumov MV, Bazya AS. Modeling of the presymptomatic stage of parkinsonism in mice: Analysis of dopamine release in the striatum. NEUROCHEM J+ 2010. [DOI: 10.1134/s1819712410020108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Sun L, Stenken JA, Brunner JE, Michel KB, Adelsberger JK, Yang AY, Zhao JJ, Musson DG. An in vivo microdialysis coupled with liquid chromatography/tandem mass spectrometry study of cortisol metabolism in monkey adipose tissue. Anal Biochem 2008; 381:214-23. [DOI: 10.1016/j.ab.2008.06.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 06/16/2008] [Accepted: 06/24/2008] [Indexed: 11/26/2022]
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10
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Tranberg M, Abbas AK, Sandberg M. In Vitro Studies on the Putative Function of N-acetylaspartate as an Osmoregulator. Neurochem Res 2007; 32:1248-55. [PMID: 17401659 DOI: 10.1007/s11064-007-9300-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Accepted: 01/30/2007] [Indexed: 10/23/2022]
Abstract
Efflux and tissue content of N-acetylaspartate (NAA) and amino acids were evaluated from cultured and acutely prepared hippocampal slices in response to changes in osmolarity. The osmoregulator taurine, but not NAA, was lost from both types of slices after moderate reductions in extracellular osmolarity (-60 mOsm) for 10-48 h. Hypoosmotic shock (-166 mOsm) for 5 min resulted in unselective efflux of several amino acids from acutely prepared slices. Notably, the efflux of taurine, but not NAA, was prominent also after the shock. Efflux of NAA was markedly enhanced by NMDA and high K(+), in particular after the stimulation period. The high K(+)-mediated efflux was decreased by high extracellular osmolarity and a NMDA-receptor antagonist. The results indicate that NAA efflux can be induced by a sudden non-physiological decrease in extracellular osmolarity but not by prolonged more moderate changes in osmolarity. The mechanisms behind the efflux of NAA by high K(+) are complex and may involve both swelling and activation of NMDA-receptors.
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Affiliation(s)
- Mattias Tranberg
- Institute of Neuroscience and Physiology, Department of Physiology, Göteborg University, Göteborg, Sweden
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11
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Nagel J, Belozertseva I, Greco S, Kashkin V, Malyshkin A, Jirgensons A, Shekunova E, Eilbacher B, Bespalov A, Danysz W. Effects of NAAG peptidase inhibitor 2-PMPA in model chronic pain - relation to brain concentration. Neuropharmacology 2006; 51:1163-71. [PMID: 16926034 DOI: 10.1016/j.neuropharm.2006.07.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Revised: 06/27/2006] [Accepted: 07/13/2006] [Indexed: 10/24/2022]
Abstract
N-acetylated-alpha-linked-acidic peptidase (NAAG peptidase) converts N-acetyl-aspartyl-glutamate (NAAG, mGluR3 agonist) into N-acetyl-aspartate and glutamate. The NAAG peptidase inhibitor 2-PMPA (2-(phosphonomethyl)pentanedioic acid) had neuroprotective activity in an animal model of stroke and anti-allodynic activity in CCI model despite its uncertain ability to penetrate the blood-brain barrier. The NAAG concentration in brain ECF under basal conditions and its alteration in relation to the brain ECF concentration of 2-PMPA is unclear. We therefore assessed those brain concentrations after i.p. administration of 2-PMPA, using in vivo microdialysis combined with LC/MS/MS analysis. Administration of 2-PMPA (50mg/kg) produced a mean peak concentration of 2-PMPA of 29.66+/-8.1microM. This concentration is about 100,000 fold more than is needed for inhibition of NAAG peptidase, and indicates very good penetration to the brain. Application of 2-PMPA was followed by a linear increase of NAAG-concentration reaching a maximum of 2.89+/-0.42microM at the end of microdialysis. However, during the time the anti-allodynic effects of 2-PMPA were observed, the NAAG concentration in the ECF did not reach levels which are likely to have an impact on any known target. It appears therefore that the observed behavioural effects of 2-PMPA may not be mediated by NAAG nor, in turn, by mGluR3 receptors.
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MESH Headings
- Analgesics, Non-Narcotic/administration & dosage
- Analgesics, Non-Narcotic/pharmacokinetics
- Analgesics, Non-Narcotic/pharmacology
- Analgesics, Non-Narcotic/therapeutic use
- Animals
- Biotransformation/drug effects
- Blood-Brain Barrier
- Brain Chemistry/drug effects
- Chronic Disease
- Dipeptides/analysis
- Dipeptides/pharmacology
- Dose-Response Relationship, Drug
- Drug Evaluation, Preclinical
- Extracellular Fluid/chemistry
- Glutamate Carboxypeptidase II/antagonists & inhibitors
- Injections, Intraperitoneal
- Ligation
- Male
- Microdialysis
- Models, Animal
- Neuralgia/drug therapy
- Neuralgia/etiology
- Neuroprotective Agents/administration & dosage
- Neuroprotective Agents/pharmacokinetics
- Neuroprotective Agents/pharmacology
- Neuroprotective Agents/therapeutic use
- Organophosphorus Compounds/administration & dosage
- Organophosphorus Compounds/pharmacokinetics
- Organophosphorus Compounds/pharmacology
- Organophosphorus Compounds/therapeutic use
- Pain Threshold/drug effects
- Pyridazines/pharmacology
- Quinolines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Rats, Wistar
- Receptors, Metabotropic Glutamate/antagonists & inhibitors
- Receptors, Metabotropic Glutamate/physiology
- Sciatic Nerve/injuries
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Affiliation(s)
- Jens Nagel
- Preclinical R & D, Merz Pharmaceuticals GmbH, Eckenheimer Landstrasse 100, 60318 Frankfurt am Main, Germany
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Kondrat RW, Kanamori K, Ross BD. In vivo microdialysis and gas-chromatography/mass-spectrometry for 13C-enrichment measurement of extracellular glutamate in rat brain. J Neurosci Methods 2002; 120:179-92. [PMID: 12385768 DOI: 10.1016/s0165-0270(02)00201-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Extracellular glutamate (GLU(ECF)) was collected by microdialysis from the corticostriatal region of awake rats, at the basal level and after elevation by perfusion of GLU uptake inhibitor, L-trans-pyrrolidine-2,4-dicarboxylic acid. Concurrently, [2,5-(13)C]glucose was infused intravenously to 13C-enrich brain GLU predominantly at C5. The 13C enrichment of GLU(ECF) was measured, after tert-butyldimethylsilylation, by gas-chromatography/mass-spectrometry. Excellent signal-to-noise ratios of the analyte signals at three selected ion-pairs were achieved at approximately 20 pmol. The fractional 13C enrichment of basal dialysate GLU C5, collected during 0.75-1.25 h of [2,5-(13)C]glucose infusion, was 0.263+/-0.01, very close to the enrichment of whole-brain (predominantly intracellular) GLU C5 measured in parallel NMR study. The result strongly suggests that the dialysate GLU consists predominantly of neurotransmitter GLU, which was 13C-enriched in, and released from, neurons by exocytosis and had diffused to the dialysis probe; the label is undiluted by 12C-GLU(ECF) present before the enrichment. Hence, our result supports the view, proposed on the basis of Ca(2+)- and tetrodotoxin-sensitivity of dialysate GLU, that basal dialysate GLU in awake non-stimulated brain mainly represents neurotransmitter GLU. Isotope labeling provides a novel method for determining the extent to which dialysate GLU reflects synaptic GLU(ECF), and for measuring its turnover under physiological or pathological conditions.
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Affiliation(s)
- Richard W Kondrat
- Mass Spectrometry Facility, University of California, Riverside, CA, USA
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Faull KF, Rafie R, Pascoe N, Marsh L, Pfefferbaum A. N-acetylaspartic acid (NAA) and N-acetylaspartylglutamic acid (NAAG) in human ventricular, subarachnoid, and lumbar cerebrospinal fluid. Neurochem Res 1999; 24:1249-61. [PMID: 10492520 DOI: 10.1023/a:1020973023059] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
N-Acetylaspartic and N-acetylaspartylglutamic acid concentrations in human ventricular, subarachnoid and lumbar cerebrospinal fluid were measured by combined gas chromatography-mass spectrometry using selected ion monitoring with deuterated internal standards. N-Acetylaspartate concentrations were in the range 55, 9, and 1 microM, respectively; N-acetylaspartylglutamate concentrations in the same fluids were in the range 8, 3 and 4 microM, respectively. There did not appear to be any difference in lumbar fluid concentrations of either compound between control subjects, schizophrenic patients, Alzheimer's disease patients and a pooled group of patients with neurological degeneration. Ventricular concentrations of both compounds were greatly increased in deceased patients suggesting that maintenance of their intracellular concentrations is probably energy dependent. The concentrations of these compounds in lumbar cerebrospinal fluid from living, and ventricular cerebrospinal fluid from deceased subjects were weakly correlated with one another. In lumbar fluid neither compound appeared to be correlated with age. Analysis of serially collected lumbar samples from two subjects showed a weak concentration gradient for both compounds. Neither antipsychotic medication nor the acid transport inhibitor probenecid had any effect on lumbar concentrations of either compound. Attempts to use anion exchange high pressure liquid chromatography with UV detection for measurement of the low concentrations of N-acetylaspartate found in cerebrospinal fluid from living subjects were unsuccessful.
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Affiliation(s)
- K F Faull
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, CA 90095, USA.
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