ABSTRACT
The field of metabolomics has witnessed the development of hundreds of computational tools, but only a few have become cornerstones of this field. While MetaboLights and Metabolomics Workbench are two well-established data repositories for metabolomics data sets, Workflows4Metabolomics and MetaboAnalyst are two well-established web-based data analysis platforms for metabolomics. Yet, the raw data stored in the aforementioned repositories lack standardization in terms of the file system format used to store the associated acquisition files. Consequently, it is not straightforward to reuse available data sets as input data in the above-mentioned data analysis resources, especially for non-expert users. This paper presents CloMet, a novel open-source modular software platform that contributes to standardization, reusability, and reproducibility in the metabolomics field. CloMet, which is available through a Docker file, converts raw and NMR-based metabolomics data from MetaboLights and Metabolomics Workbench to a file format that can be used directly either in MetaboAnalyst or in Workflows4Metabolomics. We validated both CloMet and the output data using data sets from these repositories. Overall, CloMet fills the gap between well-established data repositories and web-based statistical platforms and contributes to the consolidation of a data-driven perspective of the metabolomics field by leveraging and connecting existing data and resources.
Subject(s)
Metabolomics , Software , Reproducibility of Results , Magnetic Resonance Spectroscopy , Data AnalysisABSTRACT
Aging is a major risk factor for metabolic impairment that may lead to age-related diseases such as cardiovascular disease. Different mechanisms that may explain the interplay between aging and lipoproteins, and between aging and low-molecular-weight metabolites (LMWMs), in the metabolic dysregulation associated with age-related diseases have been described separately. Here, we statistically evaluated the possible mediation effects of LMWMs on the relationships between chronological age and lipoprotein concentrations in healthy men ranging from 19 to 75 years of age. Relative and absolute concentrations of LMWMs and lipoproteins, respectively, were assessed by nuclear magnetic resonance (NMR) spectroscopy. Multivariate linear regression and mediation analysis were conducted to explore the associations between age, lipoproteins and LMWMs. The statistical significance of the identified mediation effects was evaluated using the bootstrapping technique, and the identified mediation effects were validated on a publicly available dataset. Chronological age was statistically associated with five lipoprotein classes and subclasses. The mediation analysis showed that serine mediated 24.1% (95% CI: 22.9 - 24.7) of the effect of age on LDL-P, and glutamate mediated 17.9% (95% CI: 17.6 - 18.5) of the effect of age on large LDL-P. In the publicly available data, glutamate mediated the relationship between age and an NMR-derived surrogate of cholesterol. Our results suggest that the age-related increase in LDL particles may be mediated by a decrease in the nonessential amino acid glutamate. Future studies may contribute to a better understanding of the potential biological role of glutamate and LDL particles in aging mechanisms and age-related diseases.
ABSTRACT
OBJECTIVES: Poor immunological recovery in treated HIV-infected patients is associated with greater morbidity and mortality. To date, predictive biomarkers of this incomplete immune reconstitution have not been established. We aimed to identify a baseline metabolomic signature associated with a poor immunological recovery after antiretroviral therapy (ART) to envisage the underlying mechanistic pathways that influence the treatment response. DESIGN: This was a multicentre, prospective cohort study in ART-naive and a pre-ART low nadir (<200 cells/µl) HIV-infected patients (nâ=â64). METHODS: We obtained clinical data and metabolomic profiles for each individual, in which low molecular weight metabolites, lipids and lipoproteins (including particle concentrations and sizes) were measured by NMR spectroscopy. Immunological recovery was defined as reaching CD4 T-cell count at least 250 cells/µl after 36 months of virologically successful ART. We used univariate comparisons, Random Forest test and receiver-operating characteristic curves to identify and evaluate the predictive factors of immunological recovery after treatment. RESULTS: HIV-infected patients with a baseline metabolic pattern characterized by high levels of large high density lipoprotein (HDL) particles, HDL cholesterol and larger sizes of low density lipoprotein particles had a better immunological recovery after treatment. Conversely, patients with high ratios of non-HDL lipoprotein particles did not experience this full recovery. Medium very-low-density lipoprotein particles and glucose increased the classification power of the multivariate model despite not showing any significant differences between the two groups. CONCLUSION: In HIV-infected patients, a baseline healthier metabolomic profile is related to a better response to ART where the lipoprotein profile, mainly large HDL particles, may play a key role.
Subject(s)
Anti-Retroviral Agents/administration & dosage , HIV Infections/drug therapy , HIV Infections/pathology , Metabolome , Adult , CD4 Lymphocyte Count , Female , Follow-Up Studies , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged , Prospective Studies , Treatment OutcomeABSTRACT
A metabolome-wide genome-wide association study (mGWAS) aims to discover the effects of genetic variants on metabolome phenotypes. Most mGWASes use as phenotypes concentrations of limited sets of metabolites that can be identified and quantified from spectral information. In contrast, in an untargeted mGWAS both identification and quantification are forgone and, instead, all measured metabolome features are tested for association with genetic variants. While the untargeted approach does not discard data that may have eluded identification, the interpretation of associated features remains a challenge. To address this issue, we developed metabomatching to identify the metabolites underlying significant associations observed in untargeted mGWASes on proton NMR metabolome data. Metabomatching capitalizes on genetic spiking, the concept that because metabolome features associated with a genetic variant tend to correspond to the peaks of the NMR spectrum of the underlying metabolite, genetic association can allow for identification. Applied to the untargeted mGWASes in the SHIP and CoLaus cohorts and using 180 reference NMR spectra of the urine metabolome database, metabomatching successfully identified the underlying metabolite in 14 of 19, and 8 of 9 associations, respectively. The accuracy and efficiency of our method make it a strong contender for facilitating or complementing metabolomics analyses in large cohorts, where the availability of genetic, or other data, enables our approach, but targeted quantification is limited.
Subject(s)
Databases, Genetic , Genome-Wide Association Study/methods , Magnetic Resonance Spectroscopy/methods , Metabolomics/methods , HumansABSTRACT
BACKGROUND AND AIMS: Dietary fat composition is known to modulate circulating lipid and lipoprotein levels. Although supplementation with long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) has been shown to reduce plasma triglyceride levels, the effect of the interactions between LCn-3PUFA and the major dietary fats consumed has not been previously investigated. METHODS: In a randomized controlled parallel design clinical intervention, we examined the effect of diets rich in either saturated fatty acids (SFA) or omega-6 polyunsaturated fatty acids (n-6PUFA) on plasma lipid levels and lipoprotein profiles (lipoprotein size, concentration and distribution in subclasses) in subjects with an adequate omega 3 index. Twenty six healthy subjects went through a four-week pre-supplementation period with LCn-3PUFA and were then randomized to diets rich in either n-6PUFA or SFA both supplemented with LCn-3PUFA. RESULTS: The diet rich in n-6PUFA decreased low density lipoprotein (LDL) particle concentration (-8%, p=0.013) and LDL cholesterol (LDL-C) level (-8%, p=0.021), while the saturated fat rich diet did not affect LDL particle concentration or LDL-C levels significantly. Nevertheless, dietary saturated fatty acids increased LCn-3PUFA in plasma and tissue lipids compared with n-6PUFA, potentially reducing other cardiovascular risk factors such as inflammation and clotting tendency. CONCLUSION: Improvement on the omega 3 index of healthy subjects did not alter the known effects of dietary saturated fats and n-6PUFA on LDL profiles.
Subject(s)
Cholesterol, LDL/blood , Dietary Fats/pharmacology , Fatty Acids, Omega-3/blood , Fatty Acids, Unsaturated/blood , Fatty Acids/pharmacology , Lipoproteins, LDL/blood , Adult , Aged , Blood Coagulation , C-Reactive Protein/metabolism , Cardiovascular Diseases/epidemiology , Diet , Dietary Supplements , Erythrocytes/chemistry , Erythrocytes/metabolism , Female , Humans , Inflammation/epidemiology , Lipids/blood , Male , Middle Aged , Risk Factors , Young AdultABSTRACT
BACKGROUND: The role of circulating FABP5 on metabolic alterations is under active evaluation. On the other hand, FABP5 SNPs (rs454550 and rs79370435) seem to modulate its effect. OBJECTIVES: Our aim was to examine the role of circulating FABP5 levels and its main SNPs in atherogenic dyslipidemia (AD) assessed by 2D-Nuclear Magnetic Resonance (NMR) and related metabolic and inflammation markers. We hypothesized that circulating FABP5 may be a biomarker for metabolic risk. METHODS: We studied 459 subjects admitted to the metabolism unit because of lipid metabolism disturbances and/or associated disorders. After a 6-week lipid-lowering drug wash-out period, anamnesis and physical examination were performed. Carotid intime-media thickness (cIMT) was measured by ultrasound. FABP5, FABP4, lipids, metabolic proteins, and enzymes were determined by biochemical methods. The lipid profile was assessed by NMR. The rs454550 and rs79370435 FABP5 gene variants were also determined. RESULTS: The FABP5 plasma levels were positively correlated with adiposity, glucose metabolism, and lipolysis parameters and were associated with AD, as assessed by NMR. There was a significant positive correlation between hsCRP and FABP5. The presence of type 2 diabetes, obesity, metabolic syndrome, or AD was associated with higher FABP5 plasma levels (P < .005). The FABP5 concentrations, but not those of FABP4, were higher in patients with carotid plaques. FABP5 was a main determinant of plaque presence according to logistic regression analysis. The rare rs454550 allele was hyper-represented in nonobese subjects (P = .011). CONCLUSIONS: FABP5 is a biomarker of adiposity-associated metabolic derangements that include AD thus underscoring the concomitant presence of inflammation. FABP5 is associated with increased subclinical atherosclerosis.
Subject(s)
Atherosclerosis/complications , Dyslipidemias/complications , Dyslipidemias/metabolism , Fatty Acid-Binding Proteins/metabolism , Adult , Aged , Biomarkers/blood , Dyslipidemias/blood , Dyslipidemias/genetics , Fatty Acid-Binding Proteins/blood , Fatty Acid-Binding Proteins/genetics , Female , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged , Polymorphism, Single Nucleotide , Risk FactorsABSTRACT
Background: PCSK9 is a pivotal molecule in the regulation of lipid metabolism. Previous studies have suggested that PCSK9 expression and its function in LDL receptor regulation could be altered in the context of diabetes. The aim was to assess PCSK9 plasma levels in patients with type 2 diabetes (T2DM) and other related metabolic disorders as well as its relation to the metabolomic profile generated by nuclear magnetic resonance (NMR) and glucose homeostasis. Methods: There were recruited a total of 457 patients suffering from T2DM and other metabolic disorders (metabolic syndrome (MetS), obesity and atherogenic dyslipidaemia (AD) and other disorders). Anamnesis, anthropometry and physical examinations were conducted, and vascular and abdominal adiposity imaging were carried out. Biochemical studies were performed to determine PCSK9 plasma levels 6 weeks after lipid lowering drug wash-out in treated patients. A complete metabolomic lipid profile was also generated by NMR. The rs505151 and rs11591147 genetic variants of PCSK9 gene were identified in patients. Results: The results showed that PCSK9 levels are increased in patients with T2DM and MetS (14% and 13%;p < 0.005, respectively). Circulating PCSK9 levels were correlated with an atherogenic lipid profile and with insulin resistance parameters. PCSK9 levels were also positively associated with AD, as defined by lipoprotein particle number and size. The rs11591147 genetic variant resulted in lower levels of circulating PCSK9 and LDL cholesterol (LDL-C). Conclusions: PCSK9 plasma levels are increased in T2DM and MetS patients and are associated with LDL-C and other parameters of AD and glucose metabolism
Introducción: PCSK9 es una molécula clave en la regulación del metabolismo lipídico. Estudios previos sugieren que la expresión y función de PCSK9 entorno a la regulación del receptor LDL puede alterarse en la diabetes. El objetivo del estudio fue determinar los niveles circulantes de PCSK9 en pacientes con diabetes tipo 2 (DM) y otras enfermedades metabólicas y su relación con las lipoproteínas estudiadas mediante resonancia magnética nuclear (RMN) y la homeostasis de la glucosa. Métodos: Se estudiaron un total de 457 pacientes, afectos de DM y otras alteraciones metabólicas (síndrome metabólico [SMet], obesidad y dislipidemia aterogénica [DA] y otros). Se realizó anamnesis, antropometría, exploración física y estudio vascular de carótidas y adiposidad abdominal. Se realizó bioquímica incluyendo PCSK9 circulante (tras 6 semanas de lavado en pacientes con hipolipemiantes). Se estudió mediante RMN el perfil de lipoproteínas. Se determinaron las variantes genéticas rs505151 y rs11591147 del gen PCSK9. Resultados: Los niveles circulantes de PCSK9 están aumentados en pacientes con DM y SMet (14 y 13%; p<0.005, respectivamente). Los niveles circulantes de PCSK9 se correlacionaron de forma positiva con el perfil lipídico aterogénico y parámetros de resistencia insulínica. Los niveles circulantes de PCSK9 también se asociaron positivamente a DA, definida mediante el número y el tamaño de lipoproteínas analizado mediante RMN. Los portadores de la variante genética rs11591147 mostraron niveles inferiores de PCSK9 plasmática y cLDL. Conclusiones: Los niveles circulantes de PCSK9 están aumentados en pacientes con DM y SMet junto con parámetros de DA y metabolismo de la glucosa, más allá del cLDL
Subject(s)
Humans , Diabetes Mellitus, Type 2/genetics , Metabolic Diseases/genetics , Metabolomics/methods , Magnetic Resonance Spectroscopy/methods , Lipids/analysis , Abdominal Fat , Carotid ArteriesABSTRACT
BACKGROUND: PCSK9 is a pivotal molecule in the regulation of lipid metabolism. Previous studies have suggested that PCSK9 expression and its function in LDL receptor regulation could be altered in the context of diabetes. The aim was to assess PCSK9 plasma levels in patients with type 2 diabetes (T2DM) and other related metabolic disorders as well as its relation to the metabolomic profile generated by nuclear magnetic resonance (NMR) and glucose homeostasis. METHODS: There were recruited a total of 457 patients suffering from T2DM and other metabolic disorders (metabolic syndrome (MetS), obesity and atherogenic dyslipidaemia (AD) and other disorders). Anamnesis, anthropometry and physical examinations were conducted, and vascular and abdominal adiposity imaging were carried out. Biochemical studies were performed to determine PCSK9 plasma levels 6 weeks after lipid lowering drug wash-out in treated patients. A complete metabolomic lipid profile was also generated by NMR. The rs505151 and rs11591147 genetic variants of PCSK9 gene were identified in patients. RESULTS: The results showed that PCSK9 levels are increased in patients with T2DM and MetS (14% and 13%; p<0.005, respectively). Circulating PCSK9 levels were correlated with an atherogenic lipid profile and with insulin resistance parameters. PCSK9 levels were also positively associated with AD, as defined by lipoprotein particle number and size. The rs11591147 genetic variant resulted in lower levels of circulating PCSK9 and LDL cholesterol (LDL-C). CONCLUSIONS: PCSK9 plasma levels are increased in T2DM and MetS patients and are associated with LDL-C and other parameters of AD and glucose metabolism.
Subject(s)
Diabetes Mellitus, Type 2/blood , Metabolic Diseases/blood , Metabolic Syndrome/blood , Proprotein Convertase 9/blood , Aged , Atherosclerosis/blood , Cholesterol, LDL/blood , Cross-Sectional Studies , Dyslipidemias/blood , Female , Genetic Variation , Glucose/metabolism , Humans , Insulin Resistance , Lipids/blood , Magnetic Resonance Spectroscopy , Male , Metabolomics/methods , Middle Aged , Proprotein Convertase 9/geneticsABSTRACT
Recent studies have shown that pharmacological increases in HDL cholesterol concentrations do not necessarily translate into clinical benefits for patients, raising concerns about its predictive value for cardiovascular events. Here we hypothesize that the size-modulated lipid distribution within HDL particles is compromised in metabolic disorders that have abnormal HDL particle sizes, such as type 2 diabetes mellitus (DM2). By using NMR spectroscopy combined with a biochemical volumetric model we determined the size and spatial lipid distribution of HDL subclasses in a cohort of 26 controls and 29 DM2 patients before and after two drug treatments, one with niacin plus laropiprant and another with fenofibrate as an add-on to simvastatin. We further characterized the HDL surface properties using atomic force microscopy and fluorescent probes to show an abnormal lipid distribution within smaller HDL particles, a subclass particularly enriched in the DM2 patients. The reduction in the size, force cholesterol esters and triglycerides to emerge from the HDL core to the surface, making the outer surface of HDL more hydrophobic. Interestingly, pharmacological interventions had no effect on this undesired configuration, which may explain the lack of clinical benefits in DM2 subjects.
Subject(s)
Cardiovascular Diseases/metabolism , Cholesterol, HDL/metabolism , Diabetes Mellitus, Type 2/metabolism , Lipids/chemistry , Adult , Aged , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/etiology , Cholesterol, HDL/chemistry , Cholesterol, HDL/ultrastructure , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Female , Fenofibrate/administration & dosage , Fluorescent Dyes/chemistry , Humans , Indoles/administration & dosage , Lipid Metabolism/drug effects , Magnetic Resonance Spectroscopy , Male , Microscopy, Atomic Force , Middle Aged , Niacin , Simvastatin/administration & dosage , Surface Properties/drug effects , Triglycerides/chemistry , Triglycerides/metabolismABSTRACT
Patients with type 1 diabetes (T1D) present increased risk of cardiovascular disease (CVD). The aim of this study is to improve the assessment of lipoprotein profile in patients with T1D by using a robust developed method 1H nuclear magnetic resonance spectroscopy (1H NMR), for further correlation with clinical factors associated to CVD. Thirty patients with T1D and 30 non-diabetes control (CT) subjects, matched for gender, age, body composition (DXA, BMI, waist/hip ratio), regular physical activity levels and cardiorespiratory capacity (VO2peak), were analyzed. Dietary records and routine lipids were assessed. Serum lipoprotein particle subfractions, particle sizes, and cholesterol and triglycerides subfractions were analyzed by 1H NMR. It was evidenced that subjects with T1D presented lower concentrations of small LDL cholesterol, medium VLDL particles, large VLDL triglycerides, and total triglycerides as compared to CT subjects. Women with T1D presented a positive association with HDL size (p<0.005; R = 0.601) and large HDL triglycerides (p<0.005; R = 0.534) and negative (p<0.005; R = -0.586) to small HDL triglycerides. Body fat composition represented an important factor independently of normal BMI, with large LDL particles presenting a positive correlation to total body fat (p<0.005; R = 0.505), and total LDL cholesterol and small LDL cholesterol a positive correlation (p<0.005; R = 0.502 and R = 0.552, respectively) to abdominal fat in T1D subjects; meanwhile, in CT subjects, body fat composition was mainly associated to HDL subclasses. VO2peak was negatively associated (p<0.005; R = -0.520) to large LDL-particles only in the group of patients with T1D. In conclusion, patients with T1D with adequate glycemic control and BMI and without chronic complications presented a more favourable lipoprotein profile as compared to control counterparts. In addition, slight alterations in BMI and/or body fat composition showed to be relevant to provoking alterations in lipoproteins profiles. Finally, body fat composition appears to be a determinant for cardioprotector lipoprotein profile.
Subject(s)
Adiposity , Body Mass Index , Diabetes Mellitus, Type 1/blood , Lipoproteins/blood , Nuclear Magnetic Resonance, Biomolecular , Sex Characteristics , Adult , Cardiovascular Diseases/blood , Cardiovascular Diseases/etiology , Diabetes Complications/blood , Female , Humans , MaleABSTRACT
Hyperinsulinaemic androgen excess (HIAE) in prepubertal and pubertal girls usually precedes a broader pathological phenotype in adulthood that is associated with anovulatory infertility, metabolic syndrome and type 2 diabetes. The metabolic derangements that determine these long-term health risks remain to be clarified. Here we use NMR and MS-based metabolomics to show that serum levels of methionine sulfoxide in HIAE girls are an indicator of the degree of oxidation of methionine-148 residue in apolipoprotein-A1. Oxidation of apo-A1 in methionine-148, in turn, leads to an impaired maturation of high-density lipoproteins (HDL) that is reflected in a decline of large HDL particles. Notably, such metabolic alterations occur in the absence of impaired glucose tolerance, hyperglycemia and hypertriglyceridemia, and were partially restored after 18 months of treatment with a low-dose combination of pioglitazone, metformin and flutamide.
Subject(s)
Androgens/adverse effects , Hyperinsulinism/blood , Hyperinsulinism/metabolism , Lipoproteins, HDL/blood , Metabolomics , Adolescent , Apolipoprotein A-I/metabolism , Chromatography, Liquid , Endocrine System/metabolism , Female , Glutathione/biosynthesis , Humans , Hyperinsulinism/drug therapy , Lipoproteins, LDL/blood , Lipoproteins, VLDL/blood , Magnetic Resonance Spectroscopy , Metabolome , Methionine/analogs & derivatives , Oxidation-Reduction , Risk Factors , Spectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationABSTRACT
Determination of lipoprotein particle size and number using advanced lipoprotein tests (ALTs) is of particular importance to improve cardiovascular risk prediction. Here we present the Liposcale test, a novel ALT based on 2D diffusion-ordered (1)H NMR spectroscopy. Our method uses diffusion coefficients to provide a direct measure of the mean particle sizes and numbers. Using 177 plasma samples from healthy individuals and the concentration of ApoB and ApoA from isolated lipoprotein fractions, our test showed a stronger correlation between the NMR-derived lipoprotein particle numbers and apolipoprotein concentrations than the LipoProfile(®) test commercialized by Liposcience. We also converted LDL particle numbers to ApoB equivalents (milligrams per deciliter) and our test yielded similar values of LDL-ApoB to the LipoProfile(®) test (absolute mean bias of 8.5 and 7.4 mg/dl, respectively). In addition, our HDL particle number values were more concordant with the calibrated values determined recently using ion mobility. Finally, principal component analysis distinguished type 2 diabetic patients with and without atherogenic dyslipidemia (AD) on a second cohort of 307 subjects characterized using the Liposcale test (area under the curve = 0.88) and showed concordant relationships between variables explaining AD. Altogether, our method provides reproducible and reliable characterization of lipoprotein particles and it is applicable to pathological states such as AD.
Subject(s)
Apolipoprotein B-100/blood , Apolipoproteins A/blood , Diabetes Mellitus, Type 2/blood , Dyslipidemias/blood , Lipoproteins, LDL/blood , Nuclear Magnetic Resonance, Biomolecular/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle AgedABSTRACT
One of the main challenges in nuclear magnetic resonance (NMR) metabolomics is to obtain valuable metabolic information from large datasets of raw NMR spectra in a high throughput, automatic, and reproducible way. To date, established software packages used to match and quantify metabolites in NMR spectra remain mostly manually operated, leading to low resolution results and subject to inconsistencies not attributable to the NMR technique itself. Here, we introduce a new software package, called Dolphin, able to automatically quantify a set of target metabolites in multiple sample measurements using an approach based on 1D and 2D NMR techniques to overcome the inherent limitations of 1D (1)H-NMR spectra in metabolomics. Dolphin takes advantage of the 2D J-resolved NMR spectroscopy signal dispersion to avoid inconsistencies in signal position detection, enhancing the reliability and confidence in metabolite matching. Furthermore, in order to improve accuracy in quantification, Dolphin uses 2D NMR spectra to obtain additional information on all neighboring signals surrounding the target metabolite. We have compared the targeted profiling results of Dolphin, recorded from standard biological mixtures, with those of two well established approaches in NMR metabolomics. Overall, Dolphin produced more accurate results with the added advantage of being a fully automated and high throughput processing package.
Subject(s)
Magnetic Resonance Spectroscopy/methods , Metabolomics/methods , Software , Animals , Humans , Liver/chemistry , Liver/metabolism , Metabolome , Rats , Reproducibility of ResultsABSTRACT
Untargeted metabolomic analyses of plasma and red blood cells (RBCs) can provide complementary information on biomarkers of food consumption. To assess blood collection differences in biomarkers, fasting blood was drawn from 10 healthy individuals using sodium citrate and lithium heparin as anticoagulants. Plasma and RBCs were separated into aqueous and lipid fractions to be analyzed using 1D and 2D (1)H NMR spectroscopy. Fatty acids were analyzed using gas chromatography-mass spectrometry (GC-MS). Polyphenols were extracted from plasma and RBCs by micro-elution solid-phase extraction and analyzed by ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). (1)H NMR demonstrated higher aqueous metabolites such as glucose in plasma compared to RBCs, while RBCs contained higher ADP-ATP, creatine and acetone than plasma. Lipoproteins and their subclasses were higher in plasma than in RBCs. Percentages of saturated fatty acids (SFA) 16 : 0, 17 : 0, 20 : 0, 24 : 0 and polyunsaturated fatty acids (PUFA) 22 : 6 n-3 (docosahexaenoic acid) and 20 : 4 n-6 (arachidonic acid) were higher in RBCs than in plasma (p < 0.05), while SFA 14 : 0, monounsaturated fatty acids (MUFA) 14 : 1 n-5, 16 : 1 n-7, 17 : 1 n-7 and 18 : 1 n-9 and PUFA 18 : 3 n-3, 18 : 2 n-6, 18 : 3 n-6 and 20 : 3 n-6 were higher in plasma than in RBCs (p < 0.05). Polyphenols differed in plasma from those of RBCs. Biomarker concentrations were lower in sodium citrate compared to lithium heparin plasma. In conclusion, metabolomic profiles generated by NMR spectroscopy, GC-MS and UPLC-MS/MS analyses of RBCs versus plasma show complementary information on several specific molecular biomarkers that could be applied in nutritional assessment.
Subject(s)
Biomarkers/blood , Blood Proteins/analysis , Erythrocytes/metabolism , Adult , Aged , Blood Glucose/analysis , Eating , Fatty Acids/blood , Gas Chromatography-Mass Spectrometry , Gene Expression Profiling , Humans , Lipoproteins/blood , Male , Metabolome , Metabolomics , Middle Aged , Phospholipids/blood , Polyphenols/blood , Tandem Mass Spectrometry , Triglycerides/blood , Young AdultABSTRACT
The sizes of certain types of lipoprotein particles have been associated with an increased risk of cardiovascular disease. However, there is currently no gold standard technique for the determination of this parameter. Here, we propose an analytical procedure to measure lipoprotein particles sizes using diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY). The method was tested on six lipoprotein fractions, VLDL, IDL, LDL1, LDL2, HDL2, and HDL3, which were obtained by sequential ultracentrifugation from four patients. We performed a pulsed-field gradient experiment on each fraction to obtain a mean diffusion coefficient, and then determined the apparent hydrodynamic radius using the StokesEinstein equation. To validate the hydrodynamic radii obtained, the particle size distribution of these lipoprotein fractions was also measured using transmission electron microscopy (TEM). The standard errors of duplicate measurements of diffusion coefficient ranged from 0.5% to 1.3%, confirming the repeatability of the technique. The coefficient of determination between the hydrodynamic radii and the TEM-derived mean particle size was r2 = 0.96, and the agreement between the two techniques was 85%. Thus, DOSY experiments have proved to be accurate and reliable for estimating lipoprotein particle sizes.
Subject(s)
Lipoproteins/chemistry , Magnetic Resonance Spectroscopy/methods , Humans , Microscopy, Electron, Transmission , Particle Size , UltracentrifugationABSTRACT
Polycystic ovary syndrome (PCOS) is a variable disorder characterized by a broad spectrum of anomalies, including hyperandrogenemia, insulin resistance, dyslipidemia, body adiposity, low-grade inflammation and increased cardiovascular disease risks. Recently, a new polytherapy consisting of low-dose flutamide, metformin and pioglitazone in combination with an estro-progestagen resulted in the regulation of endocrine clinical markers in young and non-obese PCOS women. However, the metabolic processes involved in this phenotypic amelioration remain unidentified. In this work, we used NMR and MS-based untargeted metabolomics to study serum samples of young non-obese PCOS women prior to and at the end of a 30 months polytherapy receiving low-dose flutamide, metformin and pioglitazone in combination with an estro-progestagen. Our results reveal that the treatment decreased the levels of oxidized LDL particles in serum, as well as downstream metabolic oxidation products of LDL particles such as 9- and 13-HODE, azelaic acid and glutaric acid. In contrast, the radiuses of small dense LDL and large HDL particles were substantially increased after the treatment. Clinical and endocrine-metabolic markers were also monitored, showing that the level of HDL cholesterol was increased after the treatment, whereas the level of androgens and the carotid intima-media thickness were reduced. Significantly, the abundance of azelaic acid and the carotid intima-media thickness resulted in a high degree of correlation. Altogether, our results reveal that this new polytherapy markedly reverts the oxidant status of untreated PCOS women, and potentially improves the pro-atherosclerosis condition in these patients.