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Sijko-Szpańska M, Kozłowska L. Analysis of Relationships between Metabolic Changes and Selected Nutrient Intake in Women Environmentally Exposed to Arsenic. Metabolites 2024; 14:75. [PMID: 38276310 PMCID: PMC10820439 DOI: 10.3390/metabo14010075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/17/2024] [Accepted: 01/20/2024] [Indexed: 01/27/2024] Open
Abstract
Nutrients involved in the metabolism of inorganic arsenic (iAs) may play a crucial role in mitigating the adverse health effects associated with such exposure. Consequently, the objective of this study was to analyze the association between the intake levels of nutrients involved in iAs metabolism and alterations in the metabolic profile during arsenic exposure. The study cohort comprised environmentally exposed women: WL (lower total urinary arsenic (As), n = 73) and WH (higher As, n = 73). The analysis included urinary untargeted metabolomics (conducted via liquid chromatography-mass spectrometry) and the assessment of nutrient intake involved in iAs metabolism, specifically methionine, vitamins B2, B6, and B12, folate, and zinc (based on 3-day dietary records of food and beverages). In the WL group, the intake of all analyzed nutrients exhibited a negative correlation with 5 metabolites (argininosuccinic acid, 5-hydroxy-L-tryptophan, 11-trans-LTE4, mevalonic acid, aminoadipic acid), while in the WH group, it correlated with 10 metabolites (5-hydroxy-L-tryptophan, dihyroxy-1H-indole glucuronide I, 11-trans-LTE4, isovalerylglucuronide, 18-oxocortisol, 3-hydroxydecanedioic acid, S-3-oxodecanoyl cysteamine, L-arginine, p-cresol glucuronide, thromboxane B2). Furthermore, nutrient intake demonstrated a positive association with 3 metabolites in the WL group (inosine, deoxyuridine, glutamine) and the WH group (inosine, N-acetyl-L-aspartic acid, tetrahydrodeoxycorticosterone). Altering the intake of nutrients involved in iAs metabolism could be a pivotal factor in reducing the negative impact of arsenic exposure on the human body. This study underscores the significance of maintaining adequate nutrient intake, particularly in populations exposed to arsenic.
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Affiliation(s)
- Monika Sijko-Szpańska
- Laboratory of Human Metabolism Research, Department of Dietetics, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences, 02776 Warsaw, Poland
| | - Lucyna Kozłowska
- Laboratory of Human Metabolism Research, Department of Dietetics, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences, 02776 Warsaw, Poland
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Sobolev AP, Ciampa A, Ingallina C, Mannina L, Capitani D, Ernesti I, Maggi E, Businaro R, Del Ben M, Engel P, Giusti AM, Donini LM, Pinto A. Blueberry-Based Meals for Obese Patients with Metabolic Syndrome: A Multidisciplinary Metabolomic Pilot Study. Metabolites 2019; 9:metabo9070138. [PMID: 31295937 PMCID: PMC6680695 DOI: 10.3390/metabo9070138] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 12/23/2022] Open
Abstract
A pilot study was carried out on five obese/overweight patients suffering from metabolic syndrome, with the aim to evaluate postprandial effects of high fat/high glycemic load meals enriched by blueberries. Postprandial urine samples were analyzed by 1H-NMR spectroscopy after 2 and 4 h from ingestion to identify potential markers of blueberry intake. Significant decrease of methylamines, acetoacetate, acetone and succinate, known indicators of type 2 diabetes mellitus, were observed after the intake of meals enriched with blueberries. On the other hand, an accumulation of p-hydroxyphenyl-acetic acid and 3-(3’-hydroxyphenyl)-3-hydropropionic acid originating from gut microbial dehydrogenation of proanthocyanidins and procyanidins was detected. Real-time PCR-analysis of mRNAs obtained from mononuclear blood cells showed significant changes in cytokine gene expression levels after meals integrated with blueberries. In particular, the mRNAs expression of interleukin-6 (IL-6) and Transforming Growth Factor-β (TGF-β), pro and anti-inflammation cytokines, respectively, significantly decreased and increased after blueberry supplementation, indicating a positive impact of blueberry ingestion in the reduction of risk of inflammation. The combined analysis of the urine metabolome and clinical markers represents a promising approach in monitoring the metabolic impact of blueberries in persons with metabolic syndrome.
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Affiliation(s)
- Anatoly Petrovich Sobolev
- Laboratorio di Risonanza Magnetica "Annalaura Segre", Istituto per i Sistemi Biologici, CNR, via Salaria km 29.300, I-00015 Monterotondo, Italy
| | - Alessandra Ciampa
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Cinzia Ingallina
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy.
| | - Luisa Mannina
- Laboratorio di Risonanza Magnetica "Annalaura Segre", Istituto per i Sistemi Biologici, CNR, via Salaria km 29.300, I-00015 Monterotondo, Italy.
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy.
| | - Donatella Capitani
- Laboratorio di Risonanza Magnetica "Annalaura Segre", Istituto per i Sistemi Biologici, CNR, via Salaria km 29.300, I-00015 Monterotondo, Italy
| | - Ilaria Ernesti
- Sezione di Fisiopatologia Medica, Scienza dell'Alimentazione ed Endocrinologia - Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Elisa Maggi
- Dipartimento di Scienze e Biotecnologie medico-chirurgiche, Sapienza Università di Roma, Corso della Repubblica 79, 04100 Latina, Italy
| | - Rita Businaro
- Dipartimento di Scienze e Biotecnologie medico-chirurgiche, Sapienza Università di Roma, Corso della Repubblica 79, 04100 Latina, Italy
| | - Maria Del Ben
- Dipartimento di Medicina Interna e Specialità Mediche, Policlinico Umberto 1 Sapienza Università di Roma, viale del Policlinico 151, I-00185, Roma, Italy
| | - Petra Engel
- Consiglio per la Ricerca in Agricoltura e l'Analisi dell'Economia Agraria (CREA), Ufficio Rapporti Istituzionali e Relazioni Internazionali, Via Po 14, 00198 Roma, Italy
| | - Anna Maria Giusti
- Sezione di Fisiopatologia Medica, Scienza dell'Alimentazione ed Endocrinologia - Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Lorenzo M Donini
- Sezione di Fisiopatologia Medica, Scienza dell'Alimentazione ed Endocrinologia - Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
| | - Alessandro Pinto
- Sezione di Fisiopatologia Medica, Scienza dell'Alimentazione ed Endocrinologia - Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
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Maitre L, Robinson O, Martinez D, Toledano MB, Ibarluzea J, Marina LS, Sunyer J, Villanueva CM, Keun HC, Vrijheid M, Coen M. Urine Metabolic Signatures of Multiple Environmental Pollutants in Pregnant Women: An Exposome Approach. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:13469-13480. [PMID: 30285427 DOI: 10.1021/acs.est.8b02215] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Exposure to environmental pollutants, particularly during pregnancy, can have adverse consequences on child development but little is known about the effects of pollutant mixtures on endogenous metabolism in pregnant women. We aimed to identify urinary metabolic signatures associated with low level exposure to multiple environmental pollutants in pregnant women from the INMA (INfancia y Medio Ambiente) birth cohort (Spain, N = 750). 35 chemical exposures were quantified in first trimester blood samples (organochlorine pesticides, PCBs, PFAS), in cord blood (mercury), and twice in urine at 12 and 32 weeks of pregnancy (metals, phthalates, bisphenol A). 1H nuclear magnetic resonance (NMR) metabolic profiles of urine were acquired in the same samples as pollutants. We explored associations between exposures and metabolism through an exposome-metabolome wide association scan and multivariate O2PLS modeling. Novel and reproducible associations were found across two periods of pregnancy for three nonpersistent pollutants and across two subcohorts for four of the persistent pollutants. We found novel metabolic signatures associated with arsenic exposure: TMAO and dimethylamine possibly related to gut microbial methylamine metabolism and homarine related to fish intake. Tobacco smoke exposure was related to coffee metabolism and PCBs with 3-hydroxyvaleric acid, usually released under ketoacidosis. These findings will have implications for further understanding of maternal-fetal health, and health across the life-course.
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Affiliation(s)
- Léa Maitre
- ISGlobal, Institute for Global Health , Barcelona , Spain
- Universitat Pompeu Fabra (UPF) , Barcelona , Spain
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
| | - Oliver Robinson
- ISGlobal, Institute for Global Health , Barcelona , Spain
- Universitat Pompeu Fabra (UPF) , Barcelona , Spain
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
- Medical Research Council-Public Health England (MRC-PHE) Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health , Imperial College London , London , U.K
| | - David Martinez
- ISGlobal, Institute for Global Health , Barcelona , Spain
- Universitat Pompeu Fabra (UPF) , Barcelona , Spain
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
| | - Mireille B Toledano
- Medical Research Council-Public Health England (MRC-PHE) Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health , Imperial College London , London , U.K
| | - Jesús Ibarluzea
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
- School of Psychology , University of the Basque Country UPV/EHU , San Sebastian , Basque Country Spain
- Biodonostia Health Research Institute , San Sebastian , Basque Country Spain
- Sub-Directorate for Public Health of Gipuzkoa, Department of Health , Government of the Basque Country , San Sebastian , Basque Country Spain
| | - Loreto Santa Marina
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
- Biodonostia Health Research Institute , San Sebastian , Basque Country Spain
- Sub-Directorate for Public Health of Gipuzkoa, Department of Health , Government of the Basque Country , San Sebastian , Basque Country Spain
| | - Jordi Sunyer
- ISGlobal, Institute for Global Health , Barcelona , Spain
- Universitat Pompeu Fabra (UPF) , Barcelona , Spain
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
- Municipal Institute of Medical Research (IMIM-Hospital del Mar) , Barcelona , Spain
| | - Cristina M Villanueva
- ISGlobal, Institute for Global Health , Barcelona , Spain
- Universitat Pompeu Fabra (UPF) , Barcelona , Spain
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
- Municipal Institute of Medical Research (IMIM-Hospital del Mar) , Barcelona , Spain
| | - Hector C Keun
- Division of Cancer, Department of Surgery & Cancer, Faculty of Medicine , Imperial College London , U.K
| | - Martine Vrijheid
- ISGlobal, Institute for Global Health , Barcelona , Spain
- Universitat Pompeu Fabra (UPF) , Barcelona , Spain
- CIBER Epidemiología y Salud Pública (CIBERESP) , Madrid , Spain
| | - Muireann Coen
- Integrative Systems Medicine & Digestive Disease, Department of Surgery & Cancer, Faculty of Medicine , Imperial College London , U.K
- Oncology Safety, Drug Safety and Metabolism , IMED Biotech Unit, AstraZeneca, 1 Francis Crick Avenue , Cambridge CB2 0RE , U.K
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Determination of β-hydroxy-β-methylbutyrate concentration and enrichment in human plasma using chemical ionization gas chromatography tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1040:233-238. [PMID: 27856194 DOI: 10.1016/j.jchromb.2016.11.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 10/31/2016] [Accepted: 11/06/2016] [Indexed: 01/01/2023]
Abstract
Our objective was to develop a quick and simplified method for the determination of β-Hydroxy-β-methylbutyrate (HMB) and ɑ-ketoisocaproic acid (KIC) concentrations and enrichments by GC/MS/MS to determine the turnover rate of HMB in humans. In experiment 1, we provided a pulse of L-[5,5,5-2H3]leucine to younger adults in the postabsorptive state then collected blood samples over a 4h time period. In experiment 2, we provided a pulse of [3,4,methyl-13C3]HMB to older adults in the postabsorptive state then collected blood samples over a 3h time period. Plasma concentrations of KIC and HMB and MPE of KIC and HMB were determined by GC/MS/MS. Plasma enrichment of leucine was determined by LC/MS/MS. To determine plasma enrichment of [5,5,5-2H3]HMB and [3,4,methyl-13C3]HMB, samples were derivatized using pentafluorobenzyl bromide and analyzed using chemical ionization mode. The final methods used included multiple reaction monitoring of transitions 117.3>59.3 for M+0 and 120.3>59.3 for M+3. In experiment 1, peak MPE of Leu peaked at 9.76% generating a peak MPE of KIC at 2.67% and a peak HMB MPE of 0.3%. In experiment 2, the rate of appearance for HMB was 0.66μmol/kg ffm/h. We calculated that production of HMB in humans accounts for 0.66% of total leucine turnover.
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Hilvo M, de Santiago I, Gopalacharyulu P, Schmitt WD, Budczies J, Kuhberg M, Dietel M, Aittokallio T, Markowetz F, Denkert C, Sehouli J, Frezza C, Darb-Esfahani S, Braicu EI. Accumulated Metabolites of Hydroxybutyric Acid Serve as Diagnostic and Prognostic Biomarkers of Ovarian High-Grade Serous Carcinomas. Cancer Res 2016; 76:796-804. [PMID: 26685161 PMCID: PMC4762194 DOI: 10.1158/0008-5472.can-15-2298] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/01/2015] [Indexed: 11/16/2022]
Abstract
Ovarian cancer is a heterogeneous disease of low prevalence, but poor survival. Early diagnosis is critical for survival, but it is often challenging because the symptoms of ovarian cancer are subtle and become apparent only during advanced stages of the disease. Therefore, the identification of robust biomarkers of early disease is a clinical priority. Metabolomic profiling is an emerging diagnostic tool enabling the detection of biomarkers reflecting alterations in tumor metabolism, a hallmark of cancer. In this study, we performed metabolomic profiling of serum and tumor tissue from 158 patients with high-grade serous ovarian cancer (HGSOC) and 100 control patients with benign or non-neoplastic lesions. We report metabolites of hydroxybutyric acid (HBA) as novel diagnostic and prognostic biomarkers associated with tumor burden and patient survival. The accumulation of HBA metabolites caused by HGSOC was also associated with reduced expression of succinic semialdehyde dehydrogenase (encoded by ALDH5A1), and with the presence of an epithelial-to-mesenchymal transition gene signature, implying a role for these metabolic alterations in cancer cell migration and invasion. In conclusion, our findings represent the first comprehensive metabolomics analysis in HGSOC and propose a new set of metabolites as biomarkers of disease with diagnostic and prognostic capabilities.
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Affiliation(s)
- Mika Hilvo
- VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT, Espoo, Finland
| | - Ines de Santiago
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | | | | | - Jan Budczies
- Institute of Pathology, Charité University Hospital, 10117 Berlin, Germany
| | - Marc Kuhberg
- Department for Gynecology, Campus Virchow Clinic, Charité Medical University, Berlin
| | - Manfred Dietel
- Institute of Pathology, Charité University Hospital, 10117 Berlin, Germany
| | - Tero Aittokallio
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
| | - Florian Markowetz
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Carsten Denkert
- Institute of Pathology, Charité University Hospital, 10117 Berlin, Germany
| | - Jalid Sehouli
- Department for Gynecology, Campus Virchow Clinic, Charité Medical University, Berlin
- On behalf of the Tumor Bank Ovarian Cancer Network (www.toc-network.de)
| | - Christian Frezza
- MRC Cancer Unit, Hutchison/MRC Research Centre, University of Cambridge, Cambridge, UK
| | | | - Elena Ioana Braicu
- Department for Gynecology, Campus Virchow Clinic, Charité Medical University, Berlin
- On behalf of the Tumor Bank Ovarian Cancer Network (www.toc-network.de)
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Law WS, Huang PY, Ong ES, Sethi SK, Saw S, Ong CN, Li SFY. Combination of 1H nuclear magnetic resonance spectroscopy and liquid chromatography/mass spectrometry with pattern recognition techniques for evaluation of metabolic profile associated with albuminuria. J Proteome Res 2009; 8:1828-37. [PMID: 19714874 DOI: 10.1021/pr800771f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A method using 1H NMR and LC/MS with pattern recognition tools such as principal component analysis (PCA) and orthogonal projection to latent structure discriminant analysis (O-PLS-DA) was used to study the urinary metabolic profiles associated with an increase in urinary albumin in a general population. The normalized peak intensities obtained from 1H NMR and LC/MS with nonparametric two-tailed Mann-Whitney analysis was used for the identification of network of potential biomarkers corresponding to the increase of albumin in urine. The specificity of detecting the stated metabolites by 1H NMR and LC/MS was demonstrated. Our preliminary data obtained demonstrated that LC/MS may produce more distinctive metabolic profiles. For the patient group, changes in alanine, kyneurnic acid, and xanthurenic acid might be associated with changes in the tryptophan metabolism. At the same time, other metabolites that were involved in citric acid cycle, amino acid metabolism, and cellular functions were affected in the patient group. The proposed approach provided a comprehensive picture of the metabolic changes induced by the increase of protein in urine and demonstrated the advantages of using multiple diagnostic biomarkers. At the same time, the current work was demonstrated as a potential cost-effective solution of high-throughput analysis with pattern recognition tools as applied here in a real clinical situation.
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Affiliation(s)
- Wai Siang Law
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Republic of Singapore
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Salek RM, Maguire ML, Bentley E, Rubtsov DV, Hough T, Cheeseman M, Nunez D, Sweatman BC, Haselden JN, Cox RD, Connor SC, Griffin JL. A metabolomic comparison of urinary changes in type 2 diabetes in mouse, rat, and human. Physiol Genomics 2006; 29:99-108. [PMID: 17190852 DOI: 10.1152/physiolgenomics.00194.2006] [Citation(s) in RCA: 304] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Type 2 diabetes mellitus is the result of a combination of impaired insulin secretion with reduced insulin sensitivity of target tissues. There are an estimated 150 million affected individuals worldwide, of whom a large proportion remains undiagnosed because of a lack of specific symptoms early in this disorder and inadequate diagnostics. In this study, NMR-based metabolomic analysis in conjunction with multivariate statistics was applied to examine the urinary metabolic changes in two rodent models of type 2 diabetes mellitus as well as unmedicated human sufferers. The db/db mouse and obese Zucker (fa/fa) rat have autosomal recessive defects in the leptin receptor gene, causing type 2 diabetes. 1H-NMR spectra of urine were used in conjunction with uni- and multivariate statistics to identify disease-related metabolic changes in these two animal models and human sufferers. This study demonstrates metabolic similarities between the three species examined, including metabolic responses associated with general systemic stress, changes in the TCA cycle, and perturbations in nucleotide metabolism and in methylamine metabolism. All three species demonstrated profound changes in nucleotide metabolism, including that of N-methylnicotinamide and N-methyl-2-pyridone-5-carboxamide, which may provide unique biomarkers for following type 2 diabetes mellitus progression.
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Affiliation(s)
- R M Salek
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
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Carl GF, Hoffman WH, Blankenship PR, Litaker MS, Hoffman MG, Mabe PA. Diabetic ketoacidosis depletes plasma tryptophan. Endocr Res 2002; 28:91-102. [PMID: 12108794 DOI: 10.1081/erc-120004541] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Diabetic ketoacidosis (DKA) is a severe metabolic disturbance of insulin-dependent diabetes mellitus (IDDM) which has a significant effect on amino acid metabolism. Amino acids serve as precursors for various neurotransmitters which are involved in affective disorders, and patients with IDDM are known to have an increased prevalence of affective disorders. We monitored the plasma concentrations of 23 amino acids in six adolescents prior to treatment of DKA and at 6, 24 and 120 hours after initiation of treatment. The well-known increase in the concentrations of the glucogenic amino acids and the decrease in the branched-chain amino acids were observed in response to treatment of DKA. Low levels of tryptophan were found prior to treatment of DKA. Treatment increased the plasma tryptophan levels, but the mean concentration remained low throughout the sampling period. Only the glutamate-derived amino acids (glutamate, proline and glutamine) from the Krebs cycle pool were significantly affected by treatment. Glutamine declined initially, but recovered as the plasma pH normalized. Our results indicate that DKA causes a depletion of plasma tryptophan. This depletion may predispose some patients with IDDM to have affective disorders secondary to a neurotransmitter imbalance.
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Affiliation(s)
- G F Carl
- Department of Neurology, Medical College of Georgia, USA
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10
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Hušek P. Improved procedure for the derivation and gas chromatographic determination of hydroxycarboxylic acids treated with chloroformates. J Chromatogr A 1993. [DOI: 10.1016/0021-9673(93)80483-o] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hušek P. Derivatization and gas chromatographic determination of hydroxycarboxylic acids treated with chloroformates. J Chromatogr A 1991. [DOI: 10.1016/s0021-9673(01)88654-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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