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Journal articles on the topic 'NMR spectroscopy of metabolites'
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Mamone, Salvatore, Nasrollah Rezaei-Ghaleh, Felipe Opazo, Christian Griesinger, and Stefan Glöggler. "Singlet-filtered NMR spectroscopy." Science Advances 6, no. 8 (February 2020): eaaz1955. http://dx.doi.org/10.1126/sciadv.aaz1955.
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Selectively studying parts of proteins and metabolites in tissue with nuclear magnetic resonance promises new insights into molecular structures or diagnostic approaches. Nuclear spin singlet states allow the selection of signals from chemical moieties of interest in proteins or metabolites while suppressing background signal. This selection process is based on the electron-mediated coupling between two nuclear spins and their difference in resonance frequency. We introduce a generalized and versatile pulsed NMR experiment that allows populating singlet states on a broad scale of coupling patterns. This approach allowed us to filter signals from proton pairs in the Alzheimer’s disease–related b-amyloid 40 peptide and in metabolites in brain matter. In particular, for glutamine/glutamate, we have discovered a long-lived state in tissue without the typically required singlet sustaining by radiofrequency irradiation. We believe that these findings will open up new opportunities to study metabolites with a view on future in vivo applications.
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Heinzmann, Silke S., Melanie Waldenberger, Annette Peters, and Philippe Schmitt-Kopplin. "Cluster Analysis Statistical Spectroscopy for the Identification of Metabolites in 1H NMR Metabolomics." Metabolites 12, no. 10 (October 19, 2022): 992. http://dx.doi.org/10.3390/metabo12100992.
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Metabolite identification in non-targeted NMR-based metabolomics remains a challenge. While many peaks of frequently occurring metabolites are assigned, there is a high number of unknowns in high-resolution NMR spectra, hampering biological conclusions for biomarker analysis. Here, we use a cluster analysis approach to guide peak assignment via statistical correlations, which gives important information on possible structural and/or biological correlations from the NMR spectrum. Unknown peaks that cluster in close proximity to known peaks form hypotheses for their metabolite identities, thus, facilitating metabolite annotation. Subsequently, metabolite identification based on a database search, 2D NMR analysis and standard spiking is performed, whereas without a hypothesis, a full structural elucidation approach would be required. The approach allows a higher identification yield in NMR spectra, especially once pathway-related subclusters are identified.
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Lombó, Marta, Sara Ruiz-Díaz, Alfonso Gutiérrez-Adán, and María-Jesús Sánchez-Calabuig. "Sperm Metabolomics through Nuclear Magnetic Resonance Spectroscopy." Animals 11, no. 6 (June 3, 2021): 1669. http://dx.doi.org/10.3390/ani11061669.
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This report reviews current knowledge of sperm metabolomics analysis using proton nuclear magnetic resonance spectroscopy (1 H-NMR) with particular emphasis on human and farm animals. First, we present the benefits of NMR over other techniques to identify sperm metabolites and then describe the specific methodology required for NMR sperm analysis, stressing the importance of analyzing metabolites extracted from both the hydrophilic and lipophilic phases. This is followed by a description of advances produced to date in the use of NMR to diagnose infertility in humans and to identify metabolic differences among the sperm of mammalian herbivore, carnivore, and omnivore species. This last application of NMR mainly seeks to explore the possible use of lipids to fuel sperm physiology, contrary to previous theories that glycolysis and oxidative phosphorylation (OXPHOS) are the only sources of sperm energy. This review describes the use of NMR to identify sperm and seminal plasma metabolites as possible indicators of semen quality, and to examine the metabolites needed to maintain sperm motility, induce their capacitation, and consequently, to predict animal fertility.
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de Graaf, Robin A., and Kevin L. Behar. "Quantitative1H NMR Spectroscopy of Blood Plasma Metabolites." Analytical Chemistry 75, no. 9 (May 2003): 2100–2104. http://dx.doi.org/10.1021/ac020782+.
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Himmelreich, Uwe, Ray L. Somorjai, Brion Dolenko, Ok Cha Lee, Heide-Marie Daniel, Ronan Murray, Carolyn E. Mountford, and Tania C. Sorrell. "Rapid Identification of Candida Species by Using Nuclear Magnetic Resonance Spectroscopy and a Statistical Classification Strategy." Applied and Environmental Microbiology 69, no. 8 (August 2003): 4566–74. http://dx.doi.org/10.1128/aem.69.8.4566-4574.2003.
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ABSTRACT Nuclear magnetic resonance (NMR) spectra were acquired from suspensions of clinically important yeast species of the genus Candida to characterize the relationship between metabolite profiles and species identification. Major metabolites were identified by using two-dimensional correlation NMR spectroscopy. One-dimensional proton NMR spectra were analyzed by using a staged statistical classification strategy. Analysis of NMR spectra from 442 isolates of Candida albicans, C. glabrata, C. krusei, C. parapsilosis, and C. tropicalis resulted in rapid, accurate identification when compared with conventional and DNA-based identification. Spectral regions used for the classification of the five yeast species revealed species-specific differences in relative amounts of lipids, trehalose, polyols, and other metabolites. Isolates of C. parapsilosis and C. glabrata with unusual PCR fingerprinting patterns also generated atypical NMR spectra, suggesting the possibility of intraspecies discontinuity. We conclude that NMR spectroscopy combined with a statistical classification strategy is a rapid, nondestructive, and potentially valuable method for identification and chemotaxonomic characterization that may be broadly applicable to fungi and other microorganisms.
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Copeland, K. R., R. W. Yatscoff, and R. M. McKenna. "Immunosuppressive activity of cyclosporine metabolites compared and characterized by mass spectroscopy and nuclear magnetic resonance." Clinical Chemistry 36, no. 2 (February 1, 1990): 225–29. http://dx.doi.org/10.1093/clinchem/36.2.225.
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Abstract Eight cyclosporine (CsA) metabolites were isolated from the urine of renal-transplant patients by high-pressure liquid chromatography. Structure and purity of the metabolites were assessed by fast atomic bombardment/mass spectroscopy, by proton nuclear magnetic resonance (NMR), and, when the quantity of metabolites permitted, by 13C-NMR. The immunosuppressive activities (I) of the metabolites were tested in three separate in vitro systems: primary and secondary mixed lymphocyte reactions as well as by a mitogen-stimulated system. The I, as measured by comparing the concentration of each metabolite required for 50% inhibition of incorporation of [3H] thymidine, varied among the assay systems, as did the ranking of I among the test systems. In general, the I of most metabolites in all assay systems were less than 10% of that for CsA. Metabolites with single modifications exhibited the greatest I; e.g., that of M-17 was congruent to 16% of that of CsA (potency ratio 0.16) in a secondary mixed lymphocyte reaction. The significance of these findings in relation to therapeutic monitoring of CsA is discussed.
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Engelke, Udo F. H., Maria L. F. Liebrand-van Sambeek, Jan G. N. de Jong, Jules G. Leroy, Éva Morava, Jan A. M. Smeitink, and Ron A. Wevers. "N-Acetylated Metabolites in Urine: Proton Nuclear Magnetic Resonance Spectroscopic Study on Patients with Inborn Errors of Metabolism." Clinical Chemistry 50, no. 1 (January 1, 2004): 58–66. http://dx.doi.org/10.1373/clinchem.2003.020214.
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Abstract Background: There is no comprehensive analytical technique to analyze N-acetylated metabolites in urine. Many of these compounds are involved in inborn errors of metabolism. In the present study, we examined the potential of proton nuclear magnetic resonance (1H-NMR) spectroscopy as a tool to identify and quantify N-acetylated metabolites in urine of patients with various inborn errors of metabolism. Methods: We performed 1H-NMR spectroscopy on a 500 MHz spectrometer. Using a combination of one- and two-dimensional correlation spectroscopy (COSY) 1H-NMR spectra, we were able to assign and quantify resonances of characteristic N-acetylated compounds products in urine of patients with 13 inborn errors of metabolism. Results: The disease-specific N-acetylated metabolites were excreted at concentrations >100 μmol/mmol of creatinine in the patients’ urine. In control urine samples, the concentration of individual N-acetyl-containing compounds was <40 μmol/mmol of creatinine. The combination of one- and two-dimensional COSY NMR spectroscopy led to the correct diagnosis of nine different inborn errors of metabolism. No abnormalities were observed in the spectra of urine from patients with GM1- or GM2-gangliosidosis. We also determined the 1H-NMR characteristics of N-acetylated metabolites that may be relevant to human metabolism. Conclusion: 1H-NMR spectroscopy may be used to identify and quantify N-acetylated metabolites of diagnostic importance for the field of inborn errors of metabolism.
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Glinskikh, Anastasia, Olga Snytnikova, Ekaterina Zelentsova, Maria Borisova, Yuri Tsentalovich, and Andrey Akulov. "The Effect of Blood Contained in the Samples on the Metabolomic Profile of Mouse Brain Tissue: A Study by NMR Spectroscopy." Molecules 26, no. 11 (May 22, 2021): 3096. http://dx.doi.org/10.3390/molecules26113096.
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(1) Recently, metabolic profiling of the tissue in the native state or extracts of its metabolites has become increasingly important in the field of metabolomics. An important factor, in this case, is the presence of blood in a tissue sample, which can potentially lead to a change in the concentration of tissue metabolites and, as a result, distortion of experimental data and their interpretation. (2) In this paper, the metabolomic profiling based on NMR spectroscopy was performed to determine the effect of blood contained in the studied samples of brain tissue on their metabolomic profile. We used 13 male laboratory CD-1® IGS mice for this study. The animals were divided into two groups. The first group of animals (n = 7) was subjected to the perfusion procedure, and the second group of animals (n = 6) was not perfused. The brain tissues of the animals were homogenized, and the metabolite fraction was extracted with a water/methanol/chloroform solution. Samples were studied by high-frequency 1H-NMR spectroscopy with subsequent statistical data analysis. The group comparison was performed with the use of the Student’s test. We identified 36 metabolites in the brain tissue with the use of NMR spectroscopy. (3) For the major set of studied metabolites, no significant differences were found in the brain tissue metabolite concentrations in the native state and after the blood removal procedure. (4) Thus, it was shown that the presence of blood does not have a significant effect on the metabolomic profile of the brain in animals without pathologies.
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Tesevic, Vele, Ivana Aljancic, Slobodan Milosavljevic, Vlatka Vajs, Iris Djordjevic, Milka Jadranin, Nebojsa Menkovic, and Vlado Matevski. "Secondary metabolites of three endemic Centaurea L. species." Journal of the Serbian Chemical Society 79, no. 11 (2014): 1355–62. http://dx.doi.org/10.2298/jsc140318048t.
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The aerial parts of three endemic Centaurea L. species, namely C. tomorosii Micevski, C. soskae Hayek and C. galicicae Micevski, afforded sesquiterpene lactone cnicin (1) and seven flavonoids: apigenin (2), isokaempferide (3), hispidulin (4), eupatorin (5), cirsimaritin (6), santaflavone (7) and salvigenin (8). The structures of the isolated compounds were determined by UV, 1H NMR and 13C NMR spectroscopy and HR-ESI-MS spectrometry. 1H NMR spectroscopy was used as a method for quantitative analysis of sesquiterpene lactone cnicin.
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Tasic, Ljubica, Nataša Avramović, Melissa Quintero, Danijela Stanisic, Lucas G. Martins, Tassia Brena Barroso Carneiro da Costa, Milka Jadranin, et al. "A Metabonomic View on Wilms Tumor by High-Resolution Magic-Angle Spinning Nuclear Magnetic Resonance Spectroscopy." Diagnostics 12, no. 1 (January 10, 2022): 157. http://dx.doi.org/10.3390/diagnostics12010157.
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Pediatric cancer NMR-metabonomics might be a powerful tool to discover modified biochemical pathways in tumor development, improve cancer diagnosis, and, consequently, treatment. Wilms tumor (WT) is the most common kidney tumor in young children whose genetic and epigenetic abnormalities lead to cell metabolism alterations, but, so far, investigation of metabolic pathways in WT is scarce. We aimed to explore the high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) metabonomics of WT and normal kidney (NK) samples. For this study, 14 WT and 7 NK tissue samples were obtained from the same patients and analyzed. One-dimensional and two-dimensional HR-MAS NMR spectra were processed, and the one-dimensional NMR data were analyzed using chemometrics. Chemometrics enabled us to elucidate the most significant differences between the tumor and normal tissues and to discover intrinsic metabolite alterations in WT. The metabolic differences in WT tissues were revealed by a validated PLS-DA applied on HR-MAS T2-edited 1H-NMR and were assigned to 16 metabolites, such as lipids, glucose, and branched-chain amino acids (BCAAs), among others. The WT compared to NK samples showed 13 metabolites with increased concentrations and 3 metabolites with decreased concentrations. The relative BCAA concentrations were decreased in the WT while lipids, lactate, and glutamine/glutamate showed increased levels. Sixteen tissue metabolites distinguish the analyzed WT samples and point to altered glycolysis, glutaminolysis, TCA cycle, and lipid and BCAA metabolism in WT. Significant variation in the concentrations of metabolites, such as glutamine/glutamate, lipids, lactate, and BCAAs, was observed in WT and opened up a perspective for their further study and clinical validation.
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Bustamam, Muhammad Safwan Ahamad, Hamza Ahmed Pantami, Awanis Azizan, Khozirah Shaari, Chong Chou Min, Faridah Abas, Norio Nagao, et al. "Complementary Analytical Platforms of NMR Spectroscopy and LCMS Analysis in the Metabolite Profiling of Isochrysis galbana." Marine Drugs 19, no. 3 (March 2, 2021): 139. http://dx.doi.org/10.3390/md19030139.
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This study was designed to profile the metabolites of Isochrysis galbana, an indigenous and less explored microalgae species. 1H Nuclear Magnetic Resonance (NMR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LCMS) were used to establish the metabolite profiles of five different extracts of this microalga, which are hexane (Hex), ethyl acetate (EtOAc), absolute ethanol (EtOH), EtOH:water 1:1 (AqE), and 100% water (Aq). Partial least square discriminant analysis (PLS–DA) of the generated profiles revealed that EtOAc and Aq extracts contain a diverse range of metabolites as compared to the other extracts with a total of twenty-one metabolites, comprising carotenoids, polyunsaturated fatty acids, and amino acids, that were putatively identified from the NMR spectra. Meanwhile, thirty-two metabolites were successfully annotated from the LCMS/MS data, ten of which (palmitic acid, oleic acid, α-linolenic acid, arachidic acid, cholesterol, DHA, DPA, fucoxanthin, astaxanthin, and pheophytin) were similar to those present in the NMR profile. Another eleven glycerophospholipids were discovered using MS/MS-based molecular network (MN) platform. The results of this study, besides providing a better understanding of I.galbana’s chemical make-up, will be of importance in exploring this species potential as a feed ingredient in the aquaculture industry.
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Tasic, Ljubica, Nataša Avramović, Milka Jadranin, Melissa Quintero, Danijela Stanisic, Lucas G. Martins, Tássia Brena Barroso Carneiro Costa, et al. "High-Resolution Magic-Angle-Spinning NMR in Revealing Hepatoblastoma Hallmarks." Biomedicines 10, no. 12 (December 1, 2022): 3091. http://dx.doi.org/10.3390/biomedicines10123091.
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Cancer is one of the leading causes of death in children and adolescents worldwide; among the types of liver cancer, hepatoblastoma (HBL) is the most common in childhood. Although it affects only two to three individuals in a million, it is mostly asymptomatic at diagnosis, so by the time it is detected it has already advanced. There are specific recommendations regarding HBL treatment, and ongoing studies to stratify the risks of HBL, understand the pathology, and predict prognostics and survival rates. Although magnetic resonance imaging spectroscopy is frequently used in diagnostics of HBL, high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy of HBL tissues is scarce. Using this technique, we studied the alterations among tissue metabolites of ex vivo samples from (a) HBL and non-cancer liver tissues (NCL), (b) HBL and adjacent non-tumor samples, and (c) two regions of the same HBL samples, one more centralized and the other at the edge of the tumor. It was possible to identify metabolites in HBL, then metabolites from the HBL center and the border samples, and link them to altered metabolisms in tumor tissues, highlighting their potential as biochemical markers. Metabolites closely related to liver metabolisms such as some phospholipids, triacylglycerides, fatty acids, glucose, and amino acids showed differences between the tissues.
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Tynkkynen, Tuulia, Qin Wang, Jussi Ekholm, Olga Anufrieva, Pauli Ohukainen, Jouko Vepsäläinen, Minna Männikkö, et al. "Proof of concept for quantitative urine NMR metabolomics pipeline for large-scale epidemiology and genetics." International Journal of Epidemiology 48, no. 3 (January 25, 2019): 978–93. http://dx.doi.org/10.1093/ije/dyy287.
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Abstract Background Quantitative molecular data from urine are rare in epidemiology and genetics. NMR spectroscopy could provide these data in high throughput, and it has already been applied in epidemiological settings to analyse urine samples. However, quantitative protocols for large-scale applications are not available. Methods We describe in detail how to prepare urine samples and perform NMR experiments to obtain quantitative metabolic information. Semi-automated quantitative line shape fitting analyses were set up for 43 metabolites and applied to data from various analytical test samples and from 1004 individuals from a population-based epidemiological cohort. Novel analyses on how urine metabolites associate with quantitative serum NMR metabolomics data (61 metabolic measures; n = 995) were performed. In addition, confirmatory genome-wide analyses of urine metabolites were conducted (n = 578). The fully automated quantitative regression-based spectral analysis is demonstrated for creatinine and glucose (n = 4548). Results Intra-assay metabolite variations were mostly <5%, indicating high robustness and accuracy of urine NMR spectroscopy methodology per se. Intra-individual metabolite variations were large, ranging from 6% to 194%. However, population-based inter-individual metabolite variations were even larger (from 14% to 1655%), providing a sound base for epidemiological applications. Metabolic associations between urine and serum were found to be clearly weaker than those within serum and within urine, indicating that urinary metabolomics data provide independent metabolic information. Two previous genome-wide hits for formate and 2-hydroxyisobutyrate were replicated at genome-wide significance. Conclusion Quantitative urine metabolomics data suggest broad novelty for systems epidemiology. A roadmap for an open access methodology is provided.
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Altenbuchinger, Michael, Henry Berndt, Robin Kosch, Iris Lang, Jürgen Dönitz, Peter J. Oefner, Wolfram Gronwald, Helena U. Zacharias, and GCKD Study Investigators. "Bucket Fuser: Statistical Signal Extraction for 1D 1H NMR Metabolomic Data." Metabolites 12, no. 9 (August 29, 2022): 812. http://dx.doi.org/10.3390/metabo12090812.
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Untargeted metabolomics is a promising tool for identifying novel disease biomarkers and unraveling underlying pathomechanisms. Nuclear magnetic resonance (NMR) spectroscopy is particularly suited for large-scale untargeted metabolomics studies due to its high reproducibility and cost effectiveness. Here, one-dimensional (1D) 1H NMR experiments offer good sensitivity at reasonable measurement times. Their subsequent data analysis requires sophisticated data preprocessing steps, including the extraction of NMR features corresponding to specific metabolites. We developed a novel 1D NMR feature extraction procedure, called Bucket Fuser (BF), which is based on a regularized regression framework with fused group LASSO terms. The performance of the BF procedure was demonstrated using three independent NMR datasets and was benchmarked against existing state-of-the-art NMR feature extraction methods. BF dynamically constructs NMR metabolite features, the widths of which can be adjusted via a regularization parameter. BF consistently improved metabolite signal extraction, as demonstrated by our correlation analyses with absolutely quantified metabolites. It also yielded a higher proportion of statistically significant metabolite features in our differential metabolite analyses. The BF algorithm is computationally efficient and it can deal with small sample sizes. In summary, the Bucket Fuser algorithm, which is available as a supplementary python code, facilitates the fast and dynamic extraction of 1D NMR signals for the improved detection of metabolic biomarkers.
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Fennell, Timothy R., and Susan C. J. Sumner. "Identification of Metabolites of Carcinogens by13C NMR Spectroscopy." Drug Metabolism Reviews 26, no. 1-2 (January 1994): 469–81. http://dx.doi.org/10.3109/03602539409029809.
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Schewitz, Jens, Petra Gfrörer, Klaus Pusecker, Li-Hong Tseng, Klaus Albert, Ernst Bayer, Ian D. Wilson, et al. "Directly coupled CZE-NMR and CEC-NMR spectroscopy for metabolite analysis: paracetamol metabolites in human urine." Analyst 123, no. 12 (1998): 2835–37. http://dx.doi.org/10.1039/a807387b.
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Silva, Catarina L., Ana Olival, Rosa Perestrelo, Pedro Silva, Helena Tomás, and José S. Câmara. "Untargeted Urinary 1H NMR-Based Metabolomic Pattern as a Potential Platform in Breast Cancer Detection." Metabolites 9, no. 11 (November 7, 2019): 269. http://dx.doi.org/10.3390/metabo9110269.
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Breast cancer (BC) remains the second leading cause of death among women worldwide. An emerging approach based on the identification of endogenous metabolites (EMs) and the establishment of the metabolomic fingerprint of biological fluids constitutes a new frontier in medical diagnostics and a promising strategy to differentiate cancer patients from healthy individuals. In this work we aimed to establish the urinary metabolomic patterns from 40 BC patients and 38 healthy controls (CTL) using proton nuclear magnetic resonance spectroscopy (1H-NMR) as a powerful approach to identify a set of BC-specific metabolites which might be employed in the diagnosis of BC. Orthogonal partial least squares-discriminant analysis (OPLS-DA) was applied to a 1H-NMR processed data matrix. Metabolomic patterns distinguished BC from CTL urine samples, suggesting a unique metabolite profile for each investigated group. A total of 10 metabolites exhibited the highest contribution towards discriminating BC patients from healthy controls (variable importance in projection (VIP) >1, p < 0.05). The discrimination efficiency and accuracy of the urinary EMs were ascertained by receiver operating characteristic curve (ROC) analysis that allowed the identification of some metabolites with the highest sensitivities and specificities to discriminate BC patients from healthy controls (e.g. creatine, glycine, trimethylamine N-oxide, and serine). The metabolomic pathway analysis indicated several metabolism pathway disruptions, including amino acid and carbohydrate metabolisms, in BC patients, namely, glycine and butanoate metabolisms. The obtained results support the high throughput potential of NMR-based urinary metabolomics patterns in discriminating BC patients from CTL. Further investigations could unravel novel mechanistic insights into disease pathophysiology, monitor disease recurrence, and predict patient response towards therapy.
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Derveaux, Elien, Michiel Thomeer, Liesbet Mesotten, Gunter Reekmans, and Peter Adriaensens. "Detection of Lung Cancer via Blood Plasma and 1H-NMR Metabolomics: Validation by a Semi-Targeted and Quantitative Approach Using a Protein-Binding Competitor." Metabolites 11, no. 8 (August 12, 2021): 537. http://dx.doi.org/10.3390/metabo11080537.
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Metabolite profiling of blood plasma, by proton nuclear magnetic resonance (1H-NMR) spectroscopy, offers great potential for early cancer diagnosis and unraveling disruptions in cancer metabolism. Despite the essential attempts to standardize pre-analytical and external conditions, such as pH or temperature, the donor-intrinsic plasma protein concentration is highly overlooked. However, this is of utmost importance, since several metabolites bind to these proteins, resulting in an underestimation of signal intensities. This paper describes a novel 1H-NMR approach to avoid metabolite binding by adding 4 mM trimethylsilyl-2,2,3,3-tetradeuteropropionic acid (TSP) as a strong binding competitor. In addition, it is demonstrated, for the first time, that maleic acid is a reliable internal standard to quantify the human plasma metabolites without the need for protein precipitation. Metabolite spiking is further used to identify the peaks of 62 plasma metabolites and to divide the 1H-NMR spectrum into 237 well-defined integration regions, representing these 62 metabolites. A supervised multivariate classification model, trained using the intensities of these integration regions (areas under the peaks), was able to differentiate between lung cancer patients and healthy controls in a large patient cohort (n = 160), with a specificity, sensitivity, and area under the curve of 93%, 85%, and 0.95, respectively. The robustness of the classification model is shown by validation in an independent patient cohort (n = 72).
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Whitehead, Michelle C., Olivia A. Petritz, Mary Doerr, Michael K. Stoskopf, and Tara M. Harrison. "Biochemical Effects of Routine Gonadectomy on Blood of Domestic Ferrets (Mustela putorius furo)." Journal of the American Association for Laboratory Animal Science 59, no. 5 (September 1, 2020): 567–74. http://dx.doi.org/10.30802/aalas-jaalas-19-000173.
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We studied domestic ferrets (Mustela putorius furo) to evaluate the physiologic effects of routine surgery. Standard plasma biochemistry panels and 1H-NMR spectroscopy of heparinized whole blood were performed on samples taken 24 h prior to and immediately after surgery from female and male ferrets undergoing routine gonadectomy. Increases in plasma glucose, phosphorus, potassium, and creatine kinase concentrations associated with the duration of surgery were identified on plasma biochemistry panels. Whole-blood NMR spectra allowed us to identify 42 metabolites and one drug residue. Variations between pre- and postoperative metabolite concentrations were most pronounced for female ferrets, which underwent more prolonged surgery than males. Affected metabolites included organic acids and osmolytes (betaine, methylmalonate, <small>D</small>-lactate), fatty acids and lipids (2-hydroxy-3-methylbutyric acid), and amino acid groups (acetylglycine, alloisoleucine, leucine, and isoleucine). These findings indicate that 1H-NMR spectroscopy of whole blood provides insight into metabolic perturbations in domestic ferrets undergoing surgery that are not detected in routine clinical chemistry panels.
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Kim, Seonghye, Yuri Song, Seyeon Kim, Siyeong Kim, Heesam Na, Sujin Lee, Jin Chung, and Suhkmann Kim. "Identification of a Biomarker Panel for Diagnosis of Early Childhood Caries Using Salivary Metabolic Profile." Metabolites 13, no. 3 (February 27, 2023): 356. http://dx.doi.org/10.3390/metabo13030356.
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Several studies have demonstrated that nuclear magnetic resonance (NMR) metabolic profiles can differentiate patients with caries from healthy individuals; however, these studies only identified individual metabolites. The present study aimed to identify a salivary metabolite biomarker panel for the diagnosis of early childhood caries (ECC). Saliva samples from children with and without caries were analyzed using NMR spectroscopy. Multivariate and univariate analyses were performed to identify the discriminating metabolites. Selected metabolites were further evaluated and used to detect ECC. The saliva samples of children with ECC were characterized based on the increased levels of formate, glycerophosphocholine, and lactate and reduced levels of alanine, glycine, isoleucine, lysine, proline, and tyrosine. The levels of these metabolites were significantly different from those in the control in the ECC subgroup according to caries severity and correlated with the number of decayed and filled teeth or surfaces. Subsequently, an optimal salivary metabolite biomarker panel comprising formate, lactate, proline, and glycine was developed. This panel exhibited a better diagnostic performance for ECC than a single metabolite. These results demonstrate that salivary metabolic signatures can reflect oral conditions associated with dental caries, thereby emphasizing the importance of distinct salivary metabolic profiles as potential biomarkers of ECC.
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Nurani, Laela Hayu, Abdul Rohman, Anjar Windarsih, Any Guntarti, Florentinus Dika Octa Riswanto, Endang Lukitaningsih, Nurrulhidayah Ahmad Fadzillah, and Mohamad Rafi. "Metabolite Fingerprinting Using 1H-NMR Spectroscopy and Chemometrics for Classification of Three Curcuma Species from Different Origins." Molecules 26, no. 24 (December 16, 2021): 7626. http://dx.doi.org/10.3390/molecules26247626.
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Curcuma longa, Curcuma xanthorrhiza, and Curcuma manga have been widely used for herbal or traditional medicine purposes. It was reported that turmeric plants provided several biological activities such as antioxidant, anti-inflammatory, hepatoprotector, cardioprotector, and anticancer activities. Authentication of the Curcuma species is important to ensure its authenticity and to avoid adulteration practices. Plants from different origins will have different metabolite compositions because metabolites are affected by soil nutrition, climate, temperature, and humidity. 1H-NMR spectroscopy, principal component analysis (PCA), and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) were used for authentication of C. longa, C. xanthorrhiza, and C. manga from seven different origins in Indonesia. From the 1H-NMR analysis it was obtained that 14 metabolites were responsible for generating classification model such as curcumin, demethoxycurcumin, alanine, methionine, threonine, lysine, alpha-glucose, beta-glucose, sucrose, alpha-fructose, beta-fructose, fumaric acid, tyrosine, and formate. Both PCA and OPLS-DA model demonstrated goodness of fit (R2 value more than 0.8) and good predictivity (Q2 value more than 0.45). All OPLS-DA models were validated by assessing the permutation test results with high value of original R2 and Q2. It can be concluded that metabolite fingerprinting using 1H-NMR spectroscopy and chemometrics provide a powerful tool for authentication of herbal and medicinal plants.
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Crook, Alexandra A., and Robert Powers. "Quantitative NMR-Based Biomedical Metabolomics: Current Status and Applications." Molecules 25, no. 21 (November 4, 2020): 5128. http://dx.doi.org/10.3390/molecules25215128.
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Nuclear Magnetic Resonance (NMR) spectroscopy is a quantitative analytical tool commonly utilized for metabolomics analysis. Quantitative NMR (qNMR) is a field of NMR spectroscopy dedicated to the measurement of analytes through signal intensity and its linear relationship with analyte concentration. Metabolomics-based NMR exploits this quantitative relationship to identify and measure biomarkers within complex biological samples such as serum, plasma, and urine. In this review of quantitative NMR-based metabolomics, the advancements and limitations of current techniques for metabolite quantification will be evaluated as well as the applications of qNMR in biomedical metabolomics. While qNMR is limited by sensitivity and dynamic range, the simple method development, minimal sample derivatization, and the simultaneous qualitative and quantitative information provide a unique landscape for biomedical metabolomics, which is not available to other techniques. Furthermore, the non-destructive nature of NMR-based metabolomics allows for multidimensional analysis of biomarkers that facilitates unambiguous assignment and quantification of metabolites in complex biofluids.
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Avunduk, Sibel, Özgen Alankuş-Çalişkan, Tomofumi Miyamoto, Chiaki Tanaka, and Marie-Aleth Lacaille-Dubois. "Secondary Metabolites from the Roots of Paronychia chionaea." Natural Product Communications 6, no. 2 (February 2011): 1934578X1100600. http://dx.doi.org/10.1177/1934578x1100600212.
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Two novel secondary metabolites, compounds (1–2) were isolated from the roots of Paronychia chionaea. On the basis of spectroscopic data including 1D and 2D NMR experiments (COSY, TOCSY, HSQC, and HMBC), and mass spectroscopy, their structures were established as 6- C-[α-L-arabinopyranosyl-(1→2)-β-D-glucopyranosyl]-7- O-[β-D-glucopyranosyl]-luteolin 3′-methyl ether (1), and 2-(methoxy)-2-(3,5-dimethoxy 4-hydroxyphenyl)-ethane-1,2-diol 1- O-β-D-glucopyranoside (2).
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Gómez-Gallego, Carlos, Jose Morales, Daniel Monleón, Elloise du Toit, Himanshu Kumar, Kaisa Linderborg, Yumei Zhang, et al. "Human Breast Milk NMR Metabolomic Profile across Specific Geographical Locations and Its Association with the Milk Microbiota." Nutrients 10, no. 10 (September 21, 2018): 1355. http://dx.doi.org/10.3390/nu10101355.
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The composition of human breast milk is highly variable, and it can be influenced by genetics, diet, lifestyle, and other environmental factors. This study aimed to investigate the impact of geographical location and mode of delivery on the nuclear magnetic resonance spectroscopy (NMR) metabolic profile of breast milk and its relationship with the milk microbiome. Human milk metabolic and microbiota profiles were determined using NMR and 16S rRNA gene sequencing, respectively, in 79 healthy women from Finland, Spain, South Africa, and China. Up to 68 metabolites, including amino acids, oligosaccharides, and fatty acid-associated metabolites, were identified in the milk NMR spectra. The metabolite profiles showed significant differences between geographical locations, with significant differences (p < 0.05) in the levels of galactose, lacto-N-fucopentaose III, lacto-N-fucopentaose I and 2-fucosyllactose, 3-fucosyllactose, lacto-N-difucohexaose II, lacto-N-fucopentaose III, 2-hydroxybutyrate, 3-hydroxybutyrate, proline, N-acetyl lysine, methyl-histidine, dimethylamine, kynurenine, urea, creatine and creatine phosphate, formate, lactate, acetate, phosphocholine, acetylcholine, LDL, VLDL, ethanolamine, riboflavin, hippurate, spermidine, spermine and uridine. Additionally, the effect of caesarean section on milk metabolome was dependent on the geographical region. Specific interrelations between human milk metabolites and microbiota were also identified. Proteobacteria, Actinobacteria, and Bacilli were most significantly associated with the milk metabolites, being either positively or negatively correlated depending on the metabolite. Our results reveal specific milk metabolomic profiles across geographical locations and also highlight the potential interactions between human milk’s metabolites and microbes.
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Çalış, Ihsan, S. Serap Birincioǧlu, Hasan Kırmızıbekmez, Bernhard Pfeiffer, and Jörg Heilmann. "Secondary Metabolites from Asphodelus aestivus." Zeitschrift für Naturforschung B 61, no. 10 (October 1, 2006): 1304–10. http://dx.doi.org/10.1515/znb-2006-1019.
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Together with ten well known compounds, the quinic acid derivative chlorogenic acid, the nucleoside adenosine, two amino acids, tryptophan and phenylalanine, the anthraquinone derivatives, aloemodin, aloemodin acetate and chyrosphanol 1-O-gentiobioside, the flavon C-glycosides, isovitexin, isoorientin and isoorientin 4’-O-β -glucopyranoside, as well as two new acylated isoorientin derivatives, 6”-O-(malonyl)-isoorientin and 6”-O-[(S)-3-hydroxy-3-methylglutaroyl]-isoorientin, were isolated from the water soluble part of the methanolic extract of the fresh leaves of Asphodelus aestivus. All compounds were structurally identified by spectroscopic methods, including UV, MS, and NMR (1D and 2D) spectroscopy. Among the compounds isolated, chlorogenic acid and isoorientin were found to be the main compounds of the methanolic extract.
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Bottomley, P. A., and C. J. Hardy. "Rapid, reliable in vivo assays of human phosphate metabolites by nuclear magnetic resonance." Clinical Chemistry 35, no. 3 (March 1, 1989): 392–95. http://dx.doi.org/10.1093/clinchem/35.3.392.
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Abstract This accurate, reliable, and fast method of assaying absolute concentrations of phosphate metabolites noninvasively in living tissue, including that of humans, combines 31P nuclear magnetic resonance (NMR) spectroscopy and 1H NMR imaging. The images are used to measure the areas of metabolite-bearing tissue in selected sections through the subject, and 31P spectra are acquired from the same section, together with a concentration reference located on the periphery. Metabolite concentrations are calculated from the ratios of areas and integrated signal intensities. Apparatus and protocol are designed to eliminate corrections due to magnetic field nonuniformities and NMR relaxation times. Mean (and SD) concentrations of adenosine triphosphate (ATP), phosphocreatine, and inorganic phosphate (Pi) measured in the brains of 15 normal adult human volunteers with a 1.5-T NMR system were 3.03 (0.49), 5.18 (0.89), and 1.5 (0.7) mmol per liter of wet tissue, respectively. Acquisition times of only a few minutes should facilitate metabolic studies of patients with disorders in limbs and brain, particularly those affecting entire organs.
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Gowda, G. A. Nagana, and Daniel Raftery. "Quantitating Metabolites in Protein Precipitated Serum Using NMR Spectroscopy." Analytical Chemistry 86, no. 11 (May 14, 2014): 5433–40. http://dx.doi.org/10.1021/ac5005103.
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Ali, Sara, Rania El Gedaily, Andrei Mocan, Mohamed Farag, and Hesham El-Seedi. "Profiling Metabolites and Biological Activities of Sugarcane (Saccharum officinarum Linn.) Juice and its Product Molasses via a Multiplex Metabolomics Approach." Molecules 24, no. 5 (March 7, 2019): 934. http://dx.doi.org/10.3390/molecules24050934.
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Sugarcane (Saccharum officinarum L.) is an important perennial grass in the Poaceae family cultivated worldwide due to its economical and medicinal value. In this study, a combined approach using mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy was employed for the large-scale metabolite profiling of sugarcane juice and its by-product molasses. The polyphenols were analysed via UPLC-UV-ESI-MS, whereas the primary metabolites such as sugars and organic and amino acids were profiled using NMR spectroscopy and gas chromatography/mass spectrometry (GC/MS). UPLC/MS was more effective than NMR spectroscopy or GC/MS for determining differences among the metabolite compositions of the products. Under the optimized conditions, UPLC/MS led to the identification of 42 metabolites, including nine flavonoids, nine fatty acids, and two sterols. C/O Flavone glycosides were the main subclass detected, with tricin-7-O-deoxyhexosyl glucuronide being detected in sugarcane and molasses for the first time. Based on GC/MS analysis, disaccharides were the predominant species in the sugarcane juice and molasses, with sucrose accounting for 66% and 59%, respectively, by mass of all identified metabolites. The phenolic profiles of sugarcane and molasses were further investigated in relation to their in vitro antioxidant activities using free radical scavenging assays such as 2,2-Diphenyl-1-picrylhydrazyl free radical-scavenging ability (DPPH), Trolox equivalent antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP). In view of its higher total phenolic content (TPC) (196 ± 2.1 mg GAE/100 g extract) compared to that of sugarcane juice (93 ± 2.9 mg GAE/100 g extract), molasses exhibited a substantially higher antioxidant effect. Interestingly, both extracts were also found to inhibit α-glucosidase and α-amylase enzymes, suggesting a possible antihyperglycaemic effect. These findings suggest molasses may be a new source of natural antioxidants for functional foods.
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Bairaktari, Eleni, Kostas Katopodis, Kostas C. Siamopoulos, and Orestes Tsolas. "Paraquat-induced renal injury studied by 1H nuclear magnetic resonance spectroscopy of urine." Clinical Chemistry 44, no. 6 (June 1, 1998): 1256–61. http://dx.doi.org/10.1093/clinchem/44.6.1256.
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Abstract The herbicide paraquat (1,1′-dimethyl-4,4′-bipyridylium dichloride; PQ), is a poison known to cause delayed mortality due to lung and kidney injuries. High-resolution proton nuclear magnetic resonance (1H NMR) spectroscopy has been extensively applied in evaluating nephrotoxicity by the characteristic perturbations in the excretion pattern of low molecular weight endogenous metabolites. The application of the method allows the rapid localization of the renal injury noninvasively. In this study, we report 1H NMR and conventional clinical chemistry urinalysis in two patients suffering from paraquat intoxication after overdose with suicidal intent. The alterations in the urine NMR spectrum suggest necrosis of the pars recta of the proximal renal tubules. The molecule of paraquat is also clearly detected in the same spectrum. In conclusion, the rapid screening of urine by NMR spectroscopy provides information about both the identity of the poison and the abnormal pattern of endogenous metabolites that characterize the location of the injury in renal tubules and reveals alterations in unusual metabolites that are not commonly measured.
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Parlak, Yeliz, and Nuray Güzeler. "Nuclear Magnetic Resonance Spectroscopy Applications In Foods." Current Research in Nutrition and Food Science Journal 4, Special-Issue-October (October 8, 2016): 161–68. http://dx.doi.org/10.12944/crnfsj.4.special-issue-october.22.
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Nuclear magnetic resonance spectroscopy (NMR) is the most powerful technique for determining the structure of organic compounds. NMR techniques are used successfully in various food systems for quality control and research. NMR spectroscopy is used to determine structure of proteins, aminoacid profile, carotenoids, organic acids, lipid fractions, the mobility of the water in foods. NMR spectroscopy is also used to identify and quantify the metabolites in foods. Also vegetable oils, fish oils, fish and meat, milk, cheese, wheat, fruit juices, coffee, green tea, foods such as wine and beer are among the last NMR applications. In addition, NMR spectroscopy is utilized for foodomics which is a new discipline that brings food science and nutritional research together. NMR techniques used for the food authentication are one- and two-dimensional NMR techniques, high resolution liquid state 1H and 13C NMR techniques, N15 and P-31 NMR techniques, 1H HR/MAS (high resolution magic angle spinning) NMR techniques. At this study, usage purposes of nuclear magnetic resonance spectroscopy for foods were collected.
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Mahmud, Iqbal, Kamal Chowdhury, and Arezue Boroujerdi. "Tissue-Specific Metabolic Profile Study of Moringa oleifera L. Using Nuclear Magnetic Resonance Spectroscopy." Plant Tissue Culture and Biotechnology 24, no. 1 (June 22, 2014): 77–86. http://dx.doi.org/10.3329/ptcb.v24i1.19214.
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Moringa oleifera L. an important multipurpose crop, is rich in various phytochemicals: flavonoids, antioxidants, vitamins, minerals and carotenes. The purpose of this study was to profile the groups of metabolites in leaf and stem tissues of M. oleifera. Various sugars, amino acids, and organic acid derivatives were found in all of the M. oleifera tissues with different profiles and/or peak intensities depending on the tissue. 1D proton nuclear magnetic resonance (NMR) was applied for collecting metabolite spectra. Approximately 30 metabolites with 2 unknown peaks were identified with Chenomx and verified with MMCD databases. Among these metabolites, 22 were identified as common in both leaf and stem tissues. Of the remaining 8 metabolites, 4-aminobutyrate, adenosine, guanosine, tyrosine, and p-cresol were found only in leaf tissues; however, glutamate, glutamine, and tryptophan were found only in stem tissues. Biochemical pathway analysis revealed that 28 identified metabolites were interconnected with 36 different pathways as well as related to different fatty acids and secondary metabolite-synthesis biochemical pathways. It is well known that different tissues of M. oleifera have nutritional, medicinal, and therapeutic values; therefore, our main objective is to provide a publicly available M. oliefera tissue specific metabolite database. Plant Tissue Cult. & Biotech. 24(1): 77-86, 2014 (June) D. O. I. http://dx.doi.org/10.3329/ptcb.v24i1.19214
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Marak, Sengnolotha, Elena Shumilina, Nutan Kaushik, Eva Falch, and Alexander Dikiy. "Effect of Different Drying Methods on the Nutritional Value of Hibiscus sabdariffa Calyces as Revealed by NMR Metabolomics." Molecules 26, no. 6 (March 17, 2021): 1675. http://dx.doi.org/10.3390/molecules26061675.
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Red mature calyces of Hibiscus sabdariffa were collected from 16 different locations in Meghalaya, India. Samples were processed using shade drying (SD) and tray drying (TD). NMR spectroscopy was used to assess the metabolic composition of the calyces. In this study, 18 polar metabolites were assigned using 1D and 2D NMR spectra, and 10 of them were quantified. Proximate analysis showed that the TD method is more efficient at reducing moisture and maintaining the ash content of the Hibiscus biomass. NMR metabolomics indicates that the metabolite composition significantly differs between SD and TD samples and is more stable in TD plant processing. The differences in post-harvest drying has a greater impact on the metabolite composition of Hibiscus than the plant location.
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Coen, Muireann, Jennifer Bodkin, Damla Power, William A. Bubb, Uwe Himmelreich, Philip W. Kuchel, and Tania C. Sorrell. "Antifungal Effects on Metabolite Profiles of Medically Important Yeast Species Measured by Nuclear Magnetic Resonance Spectroscopy." Antimicrobial Agents and Chemotherapy 50, no. 12 (December 2006): 4018–26. http://dx.doi.org/10.1128/aac.00439-06.
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ABSTRACT Drug-induced inhibition of fungal growth is used in the diagnostic laboratory to predict therapeutic efficacy but is relatively slow, and determination of endpoints can be problematic. Nuclear magnetic resonance (NMR) spectroscopy identifies the metabolic complement of microorganisms while monitoring utilization of constituents of the incubation medium. This technique may provide a rapid and objective indicator of antifungal effects. We evaluated the effects of caspofungin, amphotericin B (AMB), and voriconazole on metabolic profiles of yeast species cultured in RPMI-2% glucose-morpholinepropanesulfonic acid buffer in microtiter plates in a proof-of-principle study. 1H NMR spectra were obtained using Bruker NMR spectrometers at 1H frequencies of 600 and 360 MHz. Metabolites were identified by two-dimensional correlation NMR spectra, and relative peak integrals were calculated from one-dimensional 1H NMR spectra. MICs were determined by a modification of the Clinical and Laboratory Standards Institute broth microdilution method M27-A. Utilization of glucose and branched-chain and aromatic amino acid substrates was accompanied by fungal production of acetate, acetaldehyde, ethanol, formate, fumarate, glycerol, lactate, pyruvate, and succinate. Clear-cut metabolic endpoints indicating a greater than 50% reduction in substrate utilization and fungal metabolite production which correlated with MICs were noted at 16 and 24 h for all three drugs. At 8 h, reductions of greater than 50% for selected metabolites were noted for caspofungin and AMB. Direct NMR-based observation of metabolic alterations in yeast cultures reveals changes in key metabolic pathways and should be evaluated formally as a rapid technique for determining susceptibility to antifungal drugs.
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Khalkhal, Ensieh, Mostafa Rezaei-Tavirani, Fariba Fathi, B. Fatemeh Nobakht M. Gh, Amir Taherkhani, Mohammad Rostami-Nejad, Nastaran Asri, and Mohammad Hossain Haidari. "Screening of Altered Metabolites and Metabolic Pathways in Celiac Disease Using NMR Spectroscopy." BioMed Research International 2021 (November 15, 2021): 1–11. http://dx.doi.org/10.1155/2021/1798783.
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Background. Celiac disease (CeD) is an autoimmune intestinal disorder caused by gluten protein consumption in genetically predisposed individuals. As biopsy sampling is an invasive procedure, finding novel noninvasive serological markers for screening of at-risk CeD population is a priority. Metabolomics is helpful in monitoring metabolite changes in body fluids and tissues. In the present study, we evaluated serum metabolite levels of CeD patients relative to healthy controls with the aim of introducing new biomarkers for population screening. Method. We compared the serum metabolic profile of CeD patients ( n = 42 ) and healthy controls ( n = 22 ) using NMR spectroscopy and multivariate analysis. Result. 25 metabolites were identified by serum metabolic profiling. Levels of 3-hydroxyisobutyric acid and isobutyrate showed significant differences in CeD patients’ samples compared with healthy controls ( p < 0.05 ). According to pathway analysis, our data demonstrated that changes in nine metabolic pathways were significantly disrupted/affected in patients with CeD. These enriched pathways are involved in aminoacyl-tRNA biosynthesis; primary bile acid biosynthesis; nitrogen metabolism; glutamine and glutamate metabolism; valine, leucine, and isoleucine biosynthesis and degradation; taurine and hypotaurine metabolism; glyoxylate and dicarboxylate metabolism; glycine, serine, and threonine metabolism; and arginine biosynthesis. Conclusion. In summary, our results demonstrated that changes in the serum level of 25 metabolites may be useful in distinguishing CeD patients from healthy controls, which have the potential to be considered candidate biomarkers of CeD.
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Yuk, Jimmy, Jennifer R. McKelvie, Myrna J. Simpson, Manfred Spraul, and André J. Simpson. "Comparison of 1-D and 2-D NMR techniques for screening earthworm responses to sub-lethal endosulfan exposure." Environmental Chemistry 7, no. 6 (2010): 524. http://dx.doi.org/10.1071/en10084.
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Environmental context The application of metabolomics from an environmental perspective depends on the analytical ability to discriminate minute changes in the organism resulting from exposure. In this study, 1-D and 2-D Nuclear Magnetic Resonance (NMR) experiments were examined to characterise the earthworm’s metabolic response to an organochlorine pesticide. 2-D NMR showed considerable improvement in discriminating exposed worms from controls and in identifying the metabolites responsible. This study demonstrates the potential of 2-D NMR in understanding subtle biochemical responses resulting from environmental exposure. Abstract Nuclear Magnetic Resonance (NMR) based metabolomics is a powerful approach to monitoring an organism’s metabolic response to environmental exposure. However, the discrimination between exposed and control groups, depends largely on the NMR technique chosen. Here, three 1-D NMR and three 2-D NMR techniques were investigated for their ability to discriminate between control earthworms (Eisenia fetida) and those exposed to a sub-lethal concentration of a commonly occurring organochlorine pesticide, endosulfan. Partial least-squares discriminant analysis found 1H–13C Heteronuclear Single Quantum Coherence (HSQC) spectroscopy to have the highest discrimination with a MANOVA value (degree of separation) three orders lower than any of the 1-D and 2-D NMR techniques. HSQC spectroscopy identified alanine, leucine, lysine, glutamate, glucose and maltose as the major metabolites of exposure to endosulfan, more than all the other techniques combined. HSQC spectroscopy in combination with a shorter 1-D experiment may prove to be an effective tool for the discrimination and identification of significant metabolites in organisms under environmental stress.
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Huang, Xueqiang, Qunwei Chen, Genjin Yang, Weixing Dai, Qingbo Lang, Juan Du, Shikai Yan, Weidong Zhang, and Changquan Ling. "Metabolic Profiling Study of Yang Deficiency Syndrome in Hepatocellular Carcinoma byH1NMR and Pattern Recognition." Evidence-Based Complementary and Alternative Medicine 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/843048.
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This study proposes a1H NMR-based metabonomic approach to explore the biochemical characteristics of Yang deficiency syndrome in hepatocellular carcinoma (HCC) based on serum metabolic profiling. Serum samples from 21 cases of Yang deficiency syndrome HCC patients (YDS-HCC) and 21 cases of non-Yang deficiency syndrome HCC patients (NYDS-HCC) were analyzed using1H NMR spectroscopy and partial least squares discriminant analysis (PLS-DA) was applied to visualize the variation patterns in metabolic profiling of sera from different groups. The differential metabolites were identified and the biochemical characteristics were analyzed. We found that the intensities of six metabolites (LDL/VLDL, isoleucine, lactate, lipids, choline, and glucose/sugars) in serum of Yang deficiency syndrome patients were lower than those of non-Yang deficiency syndrome patients. It implies that multiple metabolisms, mainly including lipid, amino acid, and energy metabolisms, are unbalanced or weakened in Yang deficiency syndrome patients with HCC. The decreased intensities of metabolites including LDL/VLDL, isoleucine, lactate, lipids, choline, and glucose/sugars in serum may be the distinctive metabolic variations of Yang deficiency syndrome patients with HCC. And these metabolites may be potential biomarkers for diagnosis of Yang deficiency syndrome in HCC.
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Raza, S. A., A. R. Chaudhary, M. W. Mumtaz, and S. Bashir. "Antioxidant, iron chelating, lipase inhibition activities and metabolite’s prediction of hyrdoethanolic leaf extract of Conocarpus erectus." Food Research 4, no. 2 (October 14, 2019): 482–87. http://dx.doi.org/10.26656/fr.2017.4(2).300.
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The current study was conducted to evaluate the antioxidant, Fe-chelating and lipase inhibition activities of hydroethanolic leaf extracts of Conocarpus erectus. The proton magnetic resonance spectroscopy (1H-NMR) was used to identify the major types of primary and secondary metabolites in extract. The 60% ethanolic extract was found to be the most effective fraction regarding antioxidant, Fe chelating and lipase inhibitory properties. The 60% ethanolic leaf extract exhibited total antioxidant power of 223.0±3.27 mg ASE/g PE, β-carotene bleaching inhibition of 81.39±2.11%, Fe-chelating of 68.21±1.17% and pancreatic lipase inhibition of 50.60±1.47%, respectively. The 1H-NMR -based prediction of metabolites provided the information for presence of polyphenolic secondary metabolites and organic acids which might be responsible for the biological activities of extract. These findings of this work may be extended for metabolite characterization, in vivo trials and toxicity determination to get benefits for functional food development with antioxidative and antiobesity attributes.
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Trivedi, A., P. Kaushik, and A. Pandey. "Identification and metabolite profiling of Sitophilus oryzae L. by 1D and 2D NMR Spectroscopy." Bulletin of Entomological Research 100, no. 3 (October 9, 2009): 287–96. http://dx.doi.org/10.1017/s0007485309990289.
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AbstractThe polyphagous insect Sitophilus oryzae L. (Coleoptera:Curculionidae) has a tremendous adaptability in feeding behaviour, making it a serious invasive pest of stored cereals. The present study identifies the metabolite composition of Sitophilus oryzae (S. oryzae) using Nuclear Magnetic Resonance (NMR) spectroscopy. Assignment of 1D-proton by NMR, 1H-1H COSY, 2D-TOCSY 1H-1H, had been done. Amongst the various biochemically important metabolites isoleucine, valine, leucine, β-hydroxybutyrate, lysine, glutamate, glutamine, proline, lactate, alanine, di-methylamine, α-glucose, β-glucose, choline, glycerophosphorylcholine and tyrosine are present in S. oryzae. In wheat-fed S. oryzae, the presence of threonine and the absence of lactate is observed. In rice-fed S. oryzae, however, the presence of lactate and the absence of threonine were observed. Barley-fed S. oryzae shows presence of both tyrosine and lactate. It is concluded that the pest S. oryzae has adaptability on different stored cereals and grains, depicting the presence of earlier reported metabolites. The present study aims to identify the key metabolic components and associated enzymes in Sitophilus oryzae fed on different cereals.
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Guo, Zhe, and Zhong-Mei Zou. "Discovery of New Secondary Metabolites by Epigenetic Regulation and NMR Comparison from the Plant Endophytic Fungus Monosporascus eutypoides." Molecules 25, no. 18 (September 12, 2020): 4192. http://dx.doi.org/10.3390/molecules25184192.
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Overexpression of the histone acetyltransferase and the 1H NMR spectroscopic experiments of the endophytic fungus Monosporascus eutypoides resulted in the isolation of two new compounds, monosporasols A (1) and B (2), and two known compounds, pestaloficin C (3) and arthrinone (4). Their planar structures and absolute configurations were determined by spectroscopic analysis including high resolution electrospray ionization mass spectroscopy (HRESIMS), one-dimensional (1D) and two-dimensional (2D) NMR, and calculated electronic circular dichroism data. Compounds 1–2 were screened in cytotoxic bioassays against HeLa, HCT-8, A549 and MCF-7 cells. Our work highlights the enormous potential of epigenetic manipulation along with the NMR comparison as an effective strategy for unlocking the chemical diversity encoded by fungal genomes.
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Prysor-Jones, R. A., J. J. Silverlight, J. S. Jenkins, A. N. Stevens, J. L. Rodrigues, and J. R. Griffiths. "31P-Nuclear magnetic resonance spectroscopy of rat pituitary tumours in vivo." Journal of Endocrinology 106, no. 3 (September 1985): 349–53. http://dx.doi.org/10.1677/joe.0.1060349.
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ABSTRACT 31P-Nuclear magnetic resonance (NMR) spectra were obtained in the living rat from 19 implanted prolactin-secreted pituitary tumours. Seven major peaks were found including those arising from the high energy phosphorus metabolites ATP and phosphocreatine. Intracellular pH of the tumours was measured and a relationship with prolactin secretion was observed, the highest plasma prolactin concentrations being associated with an intracellular pH >7·18. Repeated NMR measurements in three tumours over periods of up to 21 days revealed progressive changes with age, shown by an increase in inorganic phosphate, a decrease in high energy phosphorus metabolites and a decrease in prolactin secretion. It is concluded that NMR spectroscopy provides a useful method of studying intracellular events which accompany hormone secretion in vivo. J. Endocr. (1985) 106, 349–353
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Moussallieh, F.-M., K. Elbayed, JB Chanson, G. Rudolf, M. Piotto, J. De Seze, and IJ Namer. "Serum analysis by1H Nuclear Magnetic Resonance spectroscopy: a new tool for distinguishing neuromyelitis optica from multiple sclerosis." Multiple Sclerosis Journal 20, no. 5 (September 30, 2013): 558–65. http://dx.doi.org/10.1177/1352458513504638.
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Background:Neuromyelitis optica (NMO) and multiple sclerosis (MS), two inflammatory demyelinating diseases, are characterized by different therapeutic strategies. Currently, the only biological diagnostic tool available to distinguish NMO from MS is the specific serum autoantibody that targets aquaporin 4, but its sensitivity is low.Objective:To assess the diagnostic accuracy of metabolomic biomarker profiles in these two neurological conditions, compared to control patients.Methods:We acquired serum spectra (47 MS, 44 NMO and 42 controls) using proton nuclear magnetic resonance (1H-NMR) spectroscopy. We used multivariate pattern recognition analysis to identify disease-specific metabolic profiles.Results:The1H-NMR spectroscopic analysis evidenced two metabolites, originating probably from astrocytes, scyllo-inositol and acetate, as promising serum biomarkers of MS and NMO, respectively. In 87.8% of MS patients, scyllo-inositol increased 0.15 to 3-fold, compared to controls and in 74.3% of NMO patients, acetate increased 0.4 to 7-fold, compared to controls. Using these two metabolites simultaneously, we can discriminate MS versus NMO patients (sensitivity, 94.3%; specificity, 90.2%).Conclusion:This study demonstrates the potential of1H-NMR spectroscopy of serum as a novel, promising analytical tool to discriminate populations of patients affected by NMO or MS.
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Bertoldo, Michael J., Lydie Nadal-Desbarats, Nadine Gérard, Alexis Dubois, Patricia K. Holyoake, and Christopher G. Grupen. "Differences in the metabolomic signatures of porcine follicular fluid collected from environments associated with good and poor oocyte quality." REPRODUCTION 146, no. 3 (September 2013): 221–31. http://dx.doi.org/10.1530/rep-13-0142.
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The microenvironment of the developing follicle is critical to the acquisition of oocyte developmental competence, which is influenced by several factors including follicle size and season. The aim of this study was to characterise the metabolomic signatures of porcine follicular fluid (FF) collected from good and poor follicular environments, using high-resolution proton nuclear magnetic resonance (1H-NMR) spectroscopy. Sow ovaries were collected at slaughter, 4 days after weaning, in summer and winter. The contents of small (3–4 mm) and large (5–8 mm) diameter follicles were aspirated and pooled separately for each ovary pair. Groups classified as summer-small (n=8), summer-large (n=15), winter-small (n=9) and winter-large (n=15) were analysed by1H-NMR spectroscopy. The concentrations of 11 metabolites differed due to follicle size alone (P<0.05), including glucose, lactate, hypoxanthine and five amino acids. The concentrations of all these metabolites, except for glucose, were lower in large FF compared with small FF. Significant interaction effects of follicle size and season were found for the concentrations of glutamate, glycine,N-acetyl groups and uridine. Succinate was the only metabolite that differed in concentration due to season alone (P<0.05). The FF levels of progesterone, androstenedione and oestradiol were correlated with the concentrations of most of the metabolites examined. The results indicate that there is a distinct shift in follicular glucose metabolism as follicles increase in diameter and suggest that follicular cells may be more vulnerable to oxidative stress during the summer months. Our findings demonstrate the power of1H-NMR spectroscopy to expand our understanding of the dynamic and complex microenvironment of the developing follicle.
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Wang, Ziyan, Zuoyuan Wang, Miaomiao Jiang, Jing Yang, Qingfen Meng, Jianli Guan, Maoling Xu, and Xin Chai. "Qualitative and Quantitative Evaluation of Chemical Constituents from Shuanghuanglian Injection Using Nuclear Magnetic Resonance Spectroscopy." Journal of Analytical Methods in Chemistry 2022 (March 9, 2022): 1–11. http://dx.doi.org/10.1155/2022/7763207.
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By employing nuclear magnetic resonance (NMR), we implemented a chemical research on Shuanghuanglian injection (SHLI) and identified 17 components, including eight primary metabolites and nine secondary metabolites. Guided by the approach of network pharmacology, the potential activities were briefly predicted for seven primary metabolites except for formic acid, such as anti-inflammation, antioxidation, and cardiovascular protection. The focused primary metabolites were quantified by a proton nuclear magnetic resonance (1H-NMR) method, which was verified with good linearity and satisfactory precision, repeatability, stability, and accuracy (except for myo-inositol with mean recovery at 135.78%). Based on the successfully established method, seven primary metabolites were effectively quantified with a slight fluctuation in 20 batches of SHLIs. The average total content of these compounds was 6.85 mg/mL, accounting for 24.84% in total solid of SHLI. This research provides an alternative method for analysis of primary metabolites and contributes to the quality control of SHLI.
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Yi, Wenwen, Le Qin, Xiao-Yuan Lian, and Zhizhen Zhang. "New Antifungal Metabolites from the Mariana Trench Sediment-Associated Actinomycete Streptomyces sp. SY1965." Marine Drugs 18, no. 8 (July 24, 2020): 385. http://dx.doi.org/10.3390/md18080385.
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New streptothiazolidine A (1), streptodiketopiperazines A (2) and B (3), and (S)-1-(3-ethylphenyl)-1,2-ethanediol (4), together with eight known compounds (5–12), were isolated from the Mariana Trench sediment-associated actinomycete Streptomyces sp. SY1965. The racemic mixtures of (±)-streptodiketopiperazine (2 and 3) and (±)-1-(3-ethylphenyl)-1,2-ethanediol (4 and 5) were separated on a chiral high-performance liquid chromatography (HPLC) column. Structures of the new compounds were elucidated by their high-resolution electrospray ionization mass spectroscopy (HRESIMS) data and extensive nuclear magnetic resonance (NMR) spectroscopic analyses. Streptothiazolidine A is a novel salicylamide analogue with a unique thiazolidine-contained side chain and its absolute configuration was established by a combination of nuclear Overhauser effect spectroscopy (NOESY) experiment, electronic circular dichroism (ECD) and 13C NMR calculations. New streptothiazolidine A (1) and streptodiketopiperazines A (2) and B (3) showed antifungal activity against Candida albicans with MIC values of 47, 42, and 42 g/mL, respectively.
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Urzì, Christian, Damian Hertig, Christoph Meyer, Sally Maddah, Jean-Marc Nuoffer, and Peter Vermathen. "Determination of Intra- and Extracellular Metabolic Adaptations of 3D Cell Cultures upon Challenges in Real-Time by NMR." International Journal of Molecular Sciences 23, no. 12 (June 12, 2022): 6555. http://dx.doi.org/10.3390/ijms23126555.
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NMR flow devices provide longitudinal real-time quantitative metabolome characterisation of living cells. However, discrimination of intra- and extracellular contributions to the spectra represents a major challenge in metabolomic NMR studies. The present NMR study demonstrates the possibility to quantitatively measure both metabolic intracellular fingerprints and extracellular footprints on human control fibroblasts by using a commercially available flow tube system with a standard 5 mm NMR probe. We performed a comprehensive 3D cell culture system characterisation. Diffusion NMR was employed for intra- and extracellular metabolites separation. In addition, complementary extracellular footprints were determined. The implemented perfused NMR bioreactor system allowed the determination of 35 metabolites and intra- and extracellular separation of 19 metabolites based on diffusion rate differences. We show the reliability and sensitivity of NMR diffusion measurements to detect metabolite concentration changes in both intra- and extracellular compartments during perfusion with different selective culture media, and upon complex I inhibition with rotenone. We also demonstrate the sensitivity of extracellular footprints to determine metabolic variations at different flow rates. The current method is of potential use for the metabolomic characterisation of defect fibroblasts and for improving physiological comprehension.
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Tambay, Vincent, Valérie-Ann Raymond, Corentine Goossens, Louise Rousseau, Simon Turcotte, and Marc Bilodeau. "Metabolomics-Guided Identification of a Distinctive Hepatocellular Carcinoma Signature." Cancers 15, no. 12 (June 18, 2023): 3232. http://dx.doi.org/10.3390/cancers15123232.
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Background: Hepatocellular carcinoma (HCC) is a major contributor to cancer-related morbidity and mortality burdens globally. Given the fundamental metabolic activity of hepatocytes within the liver, hepatocarcinogenesis is bound to be characterized by alterations in metabolite profiles as a manifestation of metabolic reprogramming. Methods: HCC and adjacent non-tumoral liver specimens were obtained from patients after HCC resection. Global patterns in tissue metabolites were identified using non-targeted 1H Nuclear Magnetic Resonance (1H-NMR) spectroscopy whereas specific metabolites were quantified using targeted liquid chromatography–mass spectrometry (LC/MS). Results: Principal component analysis (PCA) within our 1H-NMR dataset identified a principal component (PC) one of 53.3%, along which the two sample groups were distinctively clustered. Univariate analysis of tissue specimens identified more than 150 metabolites significantly altered in HCC compared to non-tumoral liver. For LC/MS, PCA identified a PC1 of 45.2%, along which samples from HCC tissues and non-tumoral tissues were clearly separated. Supervised analysis (PLS–DA) identified decreases in tissue glutathione, succinate, glycerol-3-phosphate, alanine, malate, and AMP as the most important contributors to the metabolomic signature of HCC by LC/MS. Conclusions: Together, 1H-NMR and LC/MS metabolomics have the capacity to distinguish HCC from non-tumoral liver. The characterization of such distinct profiles of metabolite abundances underscores the major metabolic alterations that result from hepatocarcinogenesis.
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Perera, Asha, Catherine Soos, and Karen Machin. "Identification of Metabolomic Biomarkers of Long-Term Stress Using NMR Spectroscopy in a Diving Duck." Metabolites 12, no. 4 (April 15, 2022): 353. http://dx.doi.org/10.3390/metabo12040353.
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Human-induced environmental changes that act as long-term stressors pose significant impacts on wildlife health. Energy required for maintenance or other functions may be re-routed towards coping with stressors, ultimately resulting in fluctuations in metabolite levels associated with energy metabolism. While metabolomics approaches are used increasingly to study environmental stressors, its use in studying stress in birds is in its infancy. We implanted captive lesser scaup (Aythya affinis) with either a biodegradable corticosterone (CORT) pellet to mimic the effects of a prolonged stressor or a placebo pellet. 1D 1H nuclear magnetic resonance (NMR) spectroscopy was performed on serum samples collected over 20 days after implant surgery. We hypothesized that CORT pellet-induced physiological stress would alter energy metabolism and result in distinct metabolite profiles in ducks compared with placebo (control). Quantitative targeted metabolite analysis revealed that metabolites related to energy metabolism: glucose, formate, lactate, glutamine, 3-hydroxybutyrate, ethanolamine, indole-3- acetate, and threonine differentiated ducks with higher circulatory CORT from controls on day 2. These metabolites function as substrates or intermediates in metabolic pathways related to energy production affected by elevated serum CORT. The use of metabolomics shows promise as a novel tool to identify and characterize physiological responses to stressors in wild birds.
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Bouffiou, Jesse, Jane Ann A. Boles, and Jennifer M. Thomson. "PSXIII-20 Using 1H NMR Spectroscopy reveals metabolite markers associated to temperament and carcass quality in feedlot cattle." Journal of Animal Science 99, Supplement_3 (October 8, 2021): 438. http://dx.doi.org/10.1093/jas/skab235.784.
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Abstract The objective of this study was to identify small molecule metabolites in a serum sample taken at entry into the feedlot that can predict performance, and animal health. One-hundred and thirty-one Angus x Simmental steers from a single ranch were sampled at a commercial feedlot in Chappell, NE. Blood samples for metabolite analysis, chute score, exit velocity, and blood lactate concentration for temperament classification were collected in addition to feedlot performance data and carcass quality measurements. The GLM and LSM procedures of SAS (SAS 9.4, 2014) were used to evaluate differences between temperament classifications. Steers were divided into three exit velocity classifications one standard deviation from the mean were classified as fast and exit velocities lower than one standard deviation from the mean were slow. Forty metabolites were quantified using 1H NMR Spectroscopy from serum. Metaboloanalyst was used to analyze serum metabolites and phenotypic values using one way- ANOVA, PCA, PLS-DA, and a permutation test to cross validate. Data were normalized and scaled. No metabolites were predictive of any of the animal health metrics collected. Five metabolites were different in exit velocity class at (P < 0.01; Methanol, Isopropanol, Lactate, Isobutyrate, and Pyruvate). Similarly, seven metabolites were different in chute score classes at (P < 0.01) (Methanol, Isobutyrate, Creatinine, Dimethly Sulfone, Hippurate, Isopropanol, and Succinate). Furthermore, several metabolites in serum at entry in the feedlot were related to carcass quality metrics; Back Fat (Urea and 2-Hydroxyisobutyrate at (P < 0.01), a trend for prediction of quality grade at (P = 0.068), carcass value (P = 0.085). The relationship between serum metabolites identified on entry into the feedlot, feedlot performance traits, and eventual carcass quality warrants further research to elucidate the roles these metabolites play during the feedlot period and in predicting carcass merit.
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Liu, Yan-Yan, Zhong-Xian Yang, Li-Min Ma, Xu-Qing Wen, Huan-Lin Ji, and Ke Li. "1H-NMR spectroscopy identifies potential biomarkers in serum metabolomic signatures for early stage esophageal squamous cell carcinoma." PeerJ 7 (November 29, 2019): e8151. http://dx.doi.org/10.7717/peerj.8151.
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Background Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent types of upper gastrointestinal malignancies. Here, we used 1H nuclear magnetic resonance spectroscopy (1H-NMR) to identify potential serum biomarkers in patients with early stage ESCC. Methods Sixty-five serum samples from early stage ESCC patients (n = 25) and healthy controls (n = 40) were analysed using 1H-NMR spectroscopy. We distinguished between different metabolites through principal component analysis, partial least squares-discriminant analysis, and orthogonal partial least squares-discriminant analysis (OPLS-DA) using SIMCA-P+ version 14.0 software. Receiver operating characteristic (ROC) analysis was conducted to verify potential biomarkers. Results Using OPLS-DA, 31 altered serum metabolites were successfully identified between the groups. Based on the area under the ROC curve (AUROC), and the biomarker panel with AUROC of 0.969, six serum metabolites (α-glucose, choline, glutamine, glutamate, valine, and dihydrothymine) were selected as potential biomarkers for early stage ESCC. Dihydrothymine particularly was selected as a new feasible biomarker associated with tumor occurrence. Conclusions 1H-NMR spectroscopy may be a useful tumour detection approach in identifying useful metabolic ESCC biomarkers for early diagnosis and in the exploration of the molecular pathogenesis of ESCC.
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Ioannou, George N., G. A. Nagana Gowda, Danijel Djukovic, and Daniel Raftery. "Distinguishing NASH Histological Severity Using a Multiplatform Metabolomics Approach." Metabolites 10, no. 4 (April 24, 2020): 168. http://dx.doi.org/10.3390/metabo10040168.
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Nonalcoholic fatty liver disease (NAFLD) is categorized based on histological severity into nonalcoholic fatty liver (NAFL) or nonalcoholic steatohepatitis (NASH). We used a multiplatform metabolomics approach to identify metabolite markers and metabolic pathways that distinguish NAFL from early NASH and advanced NASH. We analyzed fasting serum samples from 57 prospectively-recruited patients with histologically-proven NAFLD, including 12 with NAFL, 31 with early NASH and 14 with advanced NASH. Metabolite profiling was performed using a combination of liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) spectroscopy analyzed with multivariate statistical and pathway analysis tools. We targeted 237 metabolites of which 158 were quantified. Multivariate analysis uncovered metabolite profile clusters for patients with NAFL, early NASH, and advanced NASH. Also, multiple individual metabolites were associated with histological severity, most notably spermidine which was more than 2-fold lower in advanced fibrosis vs. early fibrosis, in advanced NASH vs. NAFL and in advanced NASH vs. early NASH, suggesting that spermidine exercises a protective effect against development of fibrosing NASH. Furthermore, the results also showed metabolic pathway perturbations between early-NASH and advanced-NASH. In conclusion, using a combination of two reliable analytical platforms (LC-MS and NMR spectroscopy) we identified individual metabolites, metabolite clusters and metabolic pathways that were significantly different between NAFL, early-NASH, and advanced-NASH. These differences provide mechanistic insights as well as potentially important metabolic biomarker candidates that may noninvasively distinguish patients with NAFL, early-NASH, and advanced-NASH. The associations of spermidine levels with less advanced histology merit further assessment of the potential protective effects of spermidine in NAFLD.