Metabolites In Fluids Research Articles

An integrated wearable microneedle array for the continuous monitoring of multiple biomarkers in interstitial fluid.

Implementations of wearable microneedle-based arrays of sensors for the monitoring of multiple biomarkers in interstitial fluid have lacked system integration and evidence of robust analytical performance. Here we report the development and testing of a fully integrated wearable array of microneedles for the wireless and continuous real-time sensing of two metabolites (lactate and glucose, or alcohol and glucose) in the interstitial fluid of volunteers performing common daily activities. The device works with a custom smartphone app for data capture and visualization, comprises reusable electronics and a disposable microneedle array, and is optimized for system integration, cost-effective fabrication via advanced micromachining, easier assembly, biocompatibility, pain-free skin penetration and enhanced sensitivity. Single-analyte and dual-analyte measurements correlated well with the corresponding gold-standard measurements in blood or breath. Further validation of the technology in large populations with concurrent validation of sensor readouts through centralized laboratory tests should determine the robustness and utility of real-time simultaneous monitoring of several biomarkers in interstitial fluid.

Blood Metabolomics Analysis Identifies Differential Serum Metabolites in Elite and Sub-elite Swimmers.

Objective: Metabolites in body fluids, such as lactate, glucose, and creatinine, have been measured by conventional methods to evaluate physical function and performance or athletic status. The objectives of the current study were to explore the novel metabolite biomarkers in professional swimmers with different competition levels using nuclear magnetic resonance (NMR) metabolomics, and try to establish a model to identify the athletic status or predict the competitive potential. Methods: Serum samples were collected from 103 elite and 84 sub-elite level Chinese professional swimmers, and were profiled by NMR analysis. Results: Out of the thirty-six serum metabolites profiled, ten were associated with the athletic status of swimmers (with p < 0.05). When compared with sub-elite swimmers, elite swimmers had higher levels of high-density lipoprotein (HDL), unsaturated fatty acid, lactic acid, and methanol. Elite swimmers had lower levels of isoleucine, 3-hydroxybutyric acid, acetoacetate, glutamine, glycine, and α-glucose. A model with four metabolites, including HDL, glutamine, methanol, and α-glucose, was established to predict athletic status by adjusting with different covariates. The area under the curve (AUC) of the best model was 0.904 (95% CI: 0.862-0.947), with a sensitivity and specificity of 75.5 and 90.2%, respectively. Conclusion: We have identified ten metabolite biomarkers with differentially expressed levels between elite and sub-elite swimmers, the differences could result from genetic or sports level between the two cohorts. A model with four metabolites has successfully differentiated professional swimmers with different competitive levels.

Principal components from untargeted cerebrospinal fluid metabolomics associated with Alzheimer's disease biomarkers

Studying the correlation between cerebrospinal fluid (CSF) metabolites and the Alzheimer's Disease (AD) biomarkers may offer a window to the alterations of the brain metabolome and unveil potential biological mechanisms underlying AD. In this analysis, 308 CSF metabolites from 338 individuals of Wisconsin Registry for Alzheimer's Prevention and Wisconsin Alzheimer's Disease Research Center were included in a principal component analysis (PCA). The resulted principal components (PCs) were tested for association with CSF total tau (t-tau), phosphorylated tau (p-tau), amyloid β 42 (Aβ42), and Aβ42/40 ratio using linear regression models. Significant PCs were further tested with other CSF NeuroToolKit (NTK) and imaging biomarkers. Using a Bonferroni corrected p < 0.05, 5 PCs were significantly associated with CSF p-tau and t-tau and 3 PCs were significantly associated with CSF Aβ42. Pathway analysis suggested that these PCS were enriched in 6 pathways, including metabolism of caffeine and nicotinate and nicotinamide. This study provides evidence that CSF metabolites are associated with AD pathology through core AD biomarkers and other NTK markers and suggests potential pathways to follow up in future studies.

Amniotic fluid metabolites mediate maternal high fat diet expansion of group 3 innate lymphoid cells in offspring.

Abstract Introduction Previously, we demonstrated that maternal high fat diet (mHFD) exposure results in a unique pattern of microbial colonization in offspring, expansion of IL-17 producing group 3 innate lymphoid cells (ILC3) and increased susceptibility to a model of necrotizing enterocolitis (NEC). We hypothesized that amniotic fluid (AF) metabolites are modified by maternal diet and partially responsible for the phenotype in offspring. Methods To assess if AF metabolites in mHFD were unique from regular diet (RD) AF, we collected AF from E15 dams and performed non-targeted global mass spectroscopy. To determine if the mHFD AF is responsible for expansion of ILC3, we gavaged 5-day-old RD germ-free pups with mHFD and RD AF (from conventional dams) every other day and examined them at 2 weeks by flow cytometry for ILC3. mHFD mothers were supplemented with metabolites that were decreased in the mHFD AF and offspring examined for expansion of ILC3 and susceptibility to the LPS/PAF model of NEC. Results We identified 1069 metabolites in HFD and RD AF. Principal component analysis revealed that mHFD AF was uniquely clustered from RD AF. We specifically found decreases in indole, short chain fatty acid and furoic acid metabolites in HFD AF compared to RD AF. Gavage of germ-free neonatal pups with mHFD AF resulted in expansion of IL-17 producing ILC3 compared to RD AF at 2 weeks. Supplementation of mHFD dams prenatally with metabolites diminished in HFD AF resulted in decreased expansion of ILC3 and resistance to LPS/PAF model of NEC. Conclusion mHFD modifies metabolites present in AF and can expand ILC3 in germ-free offspring. Supplementation of deficient dietary metabolites in mHFD pregnant dams rescues offspring from susceptibility to NEC. Supported by NIH R01 1K12HD068369

Metabolomic responses in brain endothelial cells (CLU‐512‐hCMEC/D) to Angiotensin II and Angiotensin 1‐7

Metabolomics is the discipline focused on the study of the dynamics, composition, interactions and responses to changes in metabolites in cells, tissues and biological fluids. Vasoactive peptides such as angiotensins cause multiple metabolic changes in vascular tissues, however these changes have not been characterized in detail. Angiotensin 1‐7 is a peptide derived from angiotensin II through the action of Angiotensin Converting Enzyme type II. This exploratory study seeks to understand the metabolic responses of a human cerebral microvascular endothelial endothelial cell line to stimulation with vasoactive peptides, in vitro (Angiotensin II, Angiotensin 1‐7).MethodsWe performed single cultures of the cell line (CLU‐512‐hCMEC/D), which was treated with Ang II, Ang 1‐7 or vehicle. Cells and culture medium were sampled before and after treatments. The samples were subjected to the process of extraction of metabolites with organic solvents. Each treatment was prepared in three biological replicates and was followed by metabolite extraction. Determination of metabolic profiles was performed by multiplatform, non‐targeted, metabolomic analysis, using liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS). To determine the differences in metabolic profiles between groups and to select statistically significant metabolites, multivariate statistical analysis was performed.ResultsWe found 122 metabolites that varied between groups. In general, Ang II‐induced changes were similar to those found for Ang 1‐7. In particular, we found a reduction in the levels of several types of lipids including some bile salts, sphingolipids, glycerophospholipids and fatty acids.This study is our first step in characterizing methods to study the impact of vasoactive peptides and inflammatory molecules on the blood‐brain barrier metabolome. Studying the modulation of the vascular tissue metabolome and endothelial cells could enhance our understanding of the effect of angiotensin 1‐7 and ACE2 in pathologies such as COVID‐19.

Изменение аминокислотного профиля в системе «мать–плод» при COVID-19

Systemic nature of the human body response to SARS-CoV-2 requires dedicated analysis at the molecular level. COVID-19 during pregnancy affects maternal health and may entail complications in the early neonatal period and possibly long-term consequences for the offspring. The aim of the study was to assess the impact of COVID-19 on amino acid profiles in maternal venous blood, amniotic fluid and umbilical cord blood in order to develop a diagnostic panel accounting for possible consequences. The main group included 29 pregnant patients with a confirmed diagnosis of COVID-19 and the control group included 17 somatically healthy pregnant women. Amino acid profiles of the biological fluids were measured by high-performance liquid chromatography combined to mass spectrometry (HPLC-MS) and assessed in logistic regression models. The analysis revealed altered content of certain amino acids, their biosynthetic precursors and metabolites in the biological fluids collected from patients with COVID-19 possibly reflecting the development of systemic inflammatory reaction and associated changes in gene expression profiles. These findings may guide further research into health outcomes for neonates born from mothers infected with SARS-CoV-2 during pregnancy. The study may help to develop advanced recommendations and differential care protocols for pregnant women and newborns diagnosed with COVID-19.

Biomonitoring of ochratoxin A, 2\u2032R-ochratoxin A and citrinin in human blood serum from Switzerland

Biomonitoring of mycotoxins and their metabolites in biological fluids is increasingly used to assess human exposure. In this study, biomarkers of ochratoxin A (OTA) and citrinin (CIT) exposure were determined in a large number of serum samples from healthy blood donors in Switzerland. In 2019, 700 samples from different regions were obtained. From 240 donors, a second sample (taken 2–9 months later) was available for analysis. Moreover, 355 blood donor samples from 2005 from all regions in Switzerland and 151 additional samples from the southern Swiss region of Ticino from 2005 could be analysed.OTA, 2′R-ochratoxin A (2′R-OTA), ochratoxin alpha (OTα), CIT and dihydrocitrinone (DH-CIT) were analysed using validated targeted methods including precipitation and online SPE clean-up.OTA and 2′R-OTA were frequently detected (OTA in 99%; 2′R-OTA in 51% of the tested samples). The mean concentration in all positive samples was 0.4 ng/mL for OTA and 0.2 ng/mL for 2′R-OTA. OTα was not detected in any sample above the limit of quantification (LOQ). In contrast to OTA, CIT and DH-CIT were only quantifiable in 2% and 0.1% of the samples, respectively. No significant trend was observed between the samples from 2005 and the more recent samples, but OTA concentrations were usually higher in serum samples from the southern Swiss region of Ticino and in males compared to females.Our extensive data fit well within the framework of previously published values for the healthy adult European population.

Anxiolytic effects, metabolism and plasma pharmacokinetics of 3, 6′ -disinapoylsucrose

3,6′-disinapoylsucrose (DISS) is a bioactive oligosaccharide ester derived from Polygalae Radix. This study aims to explore the anxiolytic effects of DISS and further reveal the material basis by establishing the pharmacokinetics of DISS and its metabolites. Behavioral experiments such as the open field test (OFT) and elevated plus maze test (EPM) were performed to evaluate the anxiolytic effects of DISS in mice after oral administration. By UPLC-MS/MS analysis, DISS and its metabolites both in blood and cerebrospinal fluid were identified, and the pharmacokinetics of DISS and its metabolites were characterized in SD rats after oral administration of DISS (100 mg·kg−1). Oral DISS could increase the time and frequency of mice entering the central area of the field in OFT and open arm in EPM, which indicated DISS has good anxiolytic effects. We also identified DISS and its metabolites (sinapic acid (SA), 3,4,5-trimethoxycinnamic acid (TMCA), methyl-3,4,5-trimethoxycinnamate (TMCA-CH2), p-Coumaric acid (CA) and p-methoxycinnamic acid (MA)) in rat plasma and cerebrospinal fluid. The pharmacokinetic results showed that DISS was rapidly absorbed after administration and reached its highest concentration at 12 min, SA had the highest exposure level in vivo and was probably the main active form of DISS action, TMCA could maintain at a low concentration for a long time. In brief, we reported the anxiolytic effect of DISS firstly, revealed the cerebrospinal fluid distribution and pharmacokinetics of DISS and its metabolites. Our findings provide the basis for further insight into the mechanisms involved in the anxiolytic effects of DISS.

Study of changes in proteolytic systems of rats under conditions of experimental chronic prostatitis

The aim of our research – to analyze the mechanisms of regulation of the body's proteolytic systems during inflammation, detection of inflammation markers in blood and prostate secretions in the simulation of chronic prostatitis (CP) in rats. 1. The leading link in the pathogenesis of many diseases is a change in the structure and functions of biological membranes – membranopathy, the consequence of which is a violation of histochemical barriers, which is manifested in an increase in the excretion of certain metabolites in the extracellular fluid. In the case of experimental CP in rats, the appearance in the secretion of the prostate gland of the components of KKS, which are determined in the secretion of the normal prostate in trace amounts, was noted. Inflammatory damage to the prostate was also evidenced by an increase in the proteolytic potential of prostate secretion due to an increase in kallikrein activity on the 21st day by 807.1% (р˂0.05), which leads to massive kininogenesis. Depletion of the adaptive and compensatory potential of the prostate gland was evidenced by a decrease in prekallikrein by 21.7% (р˂0.05) compared to the intact group of animals. A sharp increase in the activity of kallikrein in CP is probably compensated by an increase in the activity of its specific inhibitor – α2-macroglobulin, the level of which in the secretion of the CP increased on 225 % on the 21st day of the experiment compared to intact rats, and the increase in proteolytic potential – by an increase of 125 % in the inhibitory activity of α1-PI, a protein of the acute phase of inflammation. An increase in the content and activity of KKS components in the secretion of the prostate testifies to its inflammatory damage and violation of the permeability of the hematoprostatic barrier, which can be an important diagnostic criterion.

Impact of Topical Interventions on the Vaginal Microbiota and Metabolome in Postmenopausal Women

Postmenopausal women with genitourinary symptoms of menopause are often prescribed vaginal estradiol or moisturizer for symptom improvement, but the impact of these treatments on the local microenvironment is poorly understood. To compare changes in the vaginal microbiota, metabolome, and pH among women using low-dose vaginal estradiol tablet or low pH moisturizer gel for 12-weeks vs low pH placebo. This is a post hoc prespecified secondary analysis of a 12-week multicenter randomized clinical trial among postmenopausal women with moderate to severe genitourinary symptoms. Women were enrolled between April 2016 and February 2017; final follow-up visits occurred in April 2017. Data were analyzed from November 2018 to July 2021. Ten-μg vaginal estradiol plus placebo gel vs placebo tablet plus vaginal moisturizer vs dual placebo. The main outcome measures were changes in the diversity and composition of the vaginal microbiota, changes in the metabolome, and pH. Of 302 postmenopausal women from the parent trial, 144 women (mean [SD] age, 61 [4] years) were included in this analysis. After 12 weeks, the microbiota was dominated with Lactobacillus and Bifidobacterium communities among 36 women (80%) in the estradiol group, compared with 16 women (36%) using moisturizer and 13 women (26%) using placebo (P < .001). The composition of vaginal fluid metabolites also varied after 12-weeks among women in the estradiol group with significant changes in 90 of 171 metabolites measured (53%) (P < .001), including an increase in lactate. The 12-week pH among women in the estradiol group was lower vs placebo (median [IQR] pH, 5 [4.5-6.0] vs 6 [5.5-7.0]; P = .005) but not the moisturizer group vs placebo (median [IQR] pH, 6 [5.5-6.5]; P = .28). There was a decrease in pH from baseline to 12-weeks within the moisturizer (median [IQR] pH, 7 [6.0-7.5] vs 6 [5.5-6.5]; P < .001) and placebo (median [IQR] pH, 7 [7.0-7.5] vs 6 [5.5-7.0]; P < .001) groups. Women with high-diversity bacterial communities at baseline exhibited greater median change in pH compared with women with low-diversity communities (median [IQR] change, -1 [-2 to -0.5] vs -0.3 [-1.1 to 0], P = .007). This secondary analysis of a randomized clinical trial found that use of vaginal estradiol tablets resulted in substantial changes in the vaginal microbiota and metabolome with a lowering in pH, particularly in women with high-diversity bacterial communities at baseline. Low pH moisturizer or placebo did not significantly impact the vaginal microbiota or metabolome despite lowering the vaginal pH. Estradiol use may offer additional genitourinary health benefits to postmenopausal women. ClinicalTrials.gov Identifier: NCT02516202.

METABOLOMICS OF OSTEOARTHRITIS WITH SYNOVITIS IN MIDDLE AGED WOMEN FROM THE IWAKI HEALTH PROMOTION PROJECT

Purpose: Osteoarthritis (OA), an age-related low-grade inflammatory disease of the synovial joints, is one of the costliest and most disabling forms of arthritis. Although prevention and an early diagnosis are prerequisites for a favorable outcome, the detailed etiology, pathophysiology, and metabolism remain unclear. Recent omics profiling approaches combined with clinical measures comprehensively assess the health status and identify deviations; metabolomics can detect many small-molecule metabolites in body fluids or tissues in a single step.

Exposure to Antineoplastic Drugs in Occupational Settings: A Systematic Review of Biological Monitoring Data.

The high toxicity of antineoplastic drugs (ADs) makes them dangerous not only for patients, but also for exposed workers. Therefore, the aim of this review was to provide an updated overview of the biological monitoring of occupational AD exposure in order to extrapolate information useful to improve risk assessment and management strategies in workplaces. Several studies demonstrated that remarkable portions of healthcare workers may have traces of these substances or their metabolites in biological fluids, although with some conflicting results. Nurses, directly engaged in AD handling, were the occupational category at higher risk of contamination, although, in some cases, personnel not involved in AD-related tasks also showed quantifiable internal doses. Overall, further research carried out on greater sample sizes appears necessary to gain deeper insight into the variability retrieved in the reported results. This may be important to understand the impact of the extent of ADs use, different handling, procedures, and cleaning practices, spill occurrence, training of the workforce, as well as the adoption of adequate collective and personal protective equipment in affecting the occupational exposure levels. This may support the achievement of the greatest clinical efficiency of such therapies while assuring the health and safety of involved workers.

Detection and characterization of simvastatin and its metabolites in rat tissues and biological fluids using MALDI high resolution mass spectrometry approach

Simvastatin (SV) is a hypolipidemic agent, and it is the 2nd most widely prescribed lipid-lowering drug. Here, the detection and characterization of SV and its metabolites was studied in selected organs/tissues (lung, liver, brain, heart and kidney) and biological samples (blood, urine and feces) of rats. MALDI Orbitrap MS was used as a high-resolution mass analyzer. 2,5-Dihydroxybenzoic acid (DHB) and 1,5-diaminonaphthalene (DAN) were used as matrices. Several sample loading methods onto the MALDI plate were attempted and dried droplet method was found to be superior. Two different cell disruption methods, pulverization and homogenization, were also evaluated for the optimum sensitivity in MALDI. Pulverization allowed the detection of more metabolites in all organs except the liver, where homogenization led to the detection of more metabolites. Altogether, 13 metabolites were detected, and one metabolite tentatively identified as a reduced product is being reported for the first time. SV and its metabolites were distributed to all the tissues studied except the brain. Overall, the results implied that the pulverized samples were more uniform and larger in surface area, resulting in their more efficient and complete extraction during sample preparation. As shown in the present study, MALDI Orbitrap MS is a useful tool to study drug and metabolite detection and characterization.

Trichloroethylene modifies energy metabolites in the amniotic fluid of Wistar rats

Exposure to trichloroethylene (TCE), an industrial solvent, is associated with several adverse pregnancy outcomes in humans and decreased fetal weight in rats. However, effects of TCE on energy metabolites in amniotic fluid, which have associations with pregnancy outcomes, has not been published previously. In the current exploratory study, timed-pregnant Wistar rats were exposed to 480 mg TCE/kg/day via vanilla wafer or to vehicle (wafer) alone from gestational day (GD) 6–16. Amniotic fluid collected on GD 16 was analyzed for metabolites important in energy metabolism using short chain fatty acid and tricarboxylic acid plus platforms (N = 4 samples/sex/treatment). TCE decreased concentrations of the following metabolites in amniotic fluid for both fetal sexes: 6-phosphogluconate, guanosine diphosphate, adenosine diphosphate, adenosine triphosphate, and flavin adenine dinucleotide. TCE decreased fructose 1,6-bisphosphate and guanosine triphosphate concentrations in amniotic fluid of male but not female fetuses. Moreover, TCE decreased uridine diphosphate-D-glucuronate concentrations, and increased arginine and phosphocreatine concentrations, in amniotic fluid of female fetuses only. No metabolites were increased in amniotic fluid of male fetuses. Pathway analysis suggested that TCE altered folate biosynthesis and pentose phosphate pathway in both sexes. Using metabolite ratios to investigate changes within specific pathways, some ratio alterations, including those in arginine metabolism and phenylalanine metabolism, were detected in females only. Ratio analysis also suggested enzymes, including gluconokinase, as potential TCE targets. Together, results from this exploratory study suggest that TCE differentially modified energy metabolites in amniotic fluid based on sex. These findings may inform future studies of TCE reproductive toxicity.

Correlations between metabolites in the synovial fluid and serum: A mouse injury study.

Osteoarthritis occurs frequently after joint injury. Currently, osteoarthritis is diagnosed by radiographic changes that are typically found after the disease has progressed to multiple tissues. The primary objective was to compare potential metabolomic biomarkers of joint injury between synovial fluid and serum in a mouse model of posttraumatic osteoarthritis. The secondary objective was to gain insight into the pathophysiology of osteoarthritis by examining metabolomic profiles after joint injury. Twelve-week-old adult female C57BL/6 mice (n = 12) were randomly assigned to control, Day 1, or Day 8 postinjury groups. Randomly selected stifle joints were subjected to a single rapid compression. At Days 1 and 8 postinjury, serum was extracted before mice were euthanized for synovial fluid collection. Metabolomic profiling detected ~2500 metabolites across serum and synovial fluid. Of these, 179 were positively correlated and 51 were negatively correlated between synovial fluid and serum, indicating the potential for the development of metabolomic biomarkers. Synovial fluid captured injury-induced differences in metabolomic profiles at both Days 1 and 8 after injury whereas serum did not. However, synovial fluid and serum were distinct at both time points after injury. In synovial fluid, pathways of interest mapped to amino acid synthesis and degradation, bupropion degradation, and transfer RNA(tRNA)charging. In serum, pathways were amino acid synthesis and degradation, the phospholipase pathway, and nicotine degradation. These results provide a rich picture of the injury response at early time points after joint injury. Furthermore, the correlations between synovial fluid and serum metabolites suggest the potential to gain insight into intra-articular pathophysiology through analysis of serum metabolites.

Monodispersed silver-gold nanorods controllable etching for ultrasensitive SERS detection of hydrogen peroxide-involved metabolites

Hydrogen peroxide (H2O2)-involved metabolites are widely engaged in cellular metabolism, and play significant roles in cell proliferation, cell growth, and signaling transduction. It is highly desirable to establish a method for the detection of H2O2-involved metabolites for applications ranging from chemical sensing to biomedical diagnosis. Herein, monodispersed sandwich Au@4-MBN@Ag@PEG nanorods (referred to as AMPRs) with bright Raman emission were developed to serve as a universal platform for detecting H2O2-involved metabolites (4-mercaptobenzonitrile is abbreviated to 4-MBN as the Raman reporter and PEG is polyethylene glycol). The system detects metabolites through changes in the surface-enhanced Raman scattering (SERS) spectrum, resulting from the controllable etching of the silver layer by the H2O2 produced by the metabolites. The integrative nanoplatform was successfully used to quantify the levels of glucose, lactate, and choline in aqueous solutions by exploiting the close linear relationship between the intensity of a SERS band and the logarithmic concentration of H2O2. The presented SERS nanoplatform demonstrated considerable practicability for the detection of glucose in cerebrospinal fluid samples (with a limit of detection (LOD) of 1.76 μM), and was capable of distinguishing infected from uninfected individuals. Therefore, the SERS sensor provides a new platform for the detection of H2O2-involved metabolites in biological fluids, and has potential for use in metabolite analysis and biomedical diagnostics.

Microbiome-metabolomics analysis of the effects of decreasing dietary crude protein content on goat rumen mictobiota and metabolites.

ObjectiveThe objective of this study was to investigate the effects of decreasing dietary crude protein content on rumen fermentation, mictobiota, and metabolites in goats.MethodsIn an 84-day feeding trial, a total of twelve male Anhui white goat kids with initial body weight 15.9±1.13 kg were selected and randomly classified into two groups, feeding a normal crude protein diet (14.8% CP, NCP) or a low crude protein diet (12.0% CP, LCP). At the end of the experimental trial (on day 84), six animals were randomly selected from each group and were slaughtered to collect rumen fluid samples for the analysis of rumen fermentation parameters, microbiome, and metabolome.ResultsThe concentrations of ammonia-nitrogen, total volatile fatty acid, acetate, and propionate were decreased (p<0.05) in the LCP group in comparison with those in the NCP group. The abundances of genera Prevotella, Campylobacter, Synergistetes, and TG5, which were associated with nitrogen metabolism, were lower (p<0.05) in the LCP group compared with those in the NCP group. The levels of 78 metabolites (74 decreased, 4 increased) in the rumen fluid were altered (p<0.05) by the treatment. Most of the ruminal metabolites that showed decreased levels in the LCP group were substrates for microbial protein synthesis. Metabolic pathway analysis showed that vitamin B6 metabolism was significantly different (p<0.05) in rumen fluid between the two treatments.ConclusionDecreased dietary protein level inhibited rumen fermentation through microbiome and metabolome shifts in goat kids. These results enhance our understanding of ruminal bacteria and metabolites of goat fed a low protein diet.

Identification of cerebrospinal fluid metabolites as biomarkers for neurobrucellosis by liquid chromatography-mass spectrometry approach

ABSTRACT Neurobrucellosis is the most morbid form in brucellosis disease. Metabolomics is an emerging method which intends to explore the global alterations of various metabolites in samples. We aimed to identify metabolites in cerebrospinal fluid (CSF) as biomarkers that were potentially unique for neurobrucellosis. CSF samples from 25 neurobrucellosis patients and 25 normal controls (uninfected patients with hydrocephalus) were collected for metabolite detection using liquid chromatography-mass spectrometry (LC-MS) approach. Inflammatory cytokines in CSF were measured with Enzyme-linked immunosorbent assay (ELISA). The base peak chromatogram in CSF samples showed that small-molecule metabolites were well separated. Principal Component Analysis (PCA) analysis exhibited the examined samples were arranged in two main clusters in accordance with their group. Projection to Latent Structures Discriminant Analysis (PLS-DA) revealed there was a noticeable separation between neurobrucellosis and normal groups. Orthogonal Partial Least-Squares-Discriminant Analysis (OPLS-DA) could responsibly illuminate the differences between neurobrucellosis and normal controls. Neurobrucellosis showed a total of 155 differentiated metabolites. Prominent potential biomarkers including 30 metabolites were then selected out, regarded as more capable of distinguishing neurobrucellosis. TNF-α and IL-6 in CSF were remarkably increased in neurobrucellosis. We presented the heatmaps and correlation analyses among the identified 30 potential biomarkers. In conclusion, this study showed that CSF metabolomics based on LC-MS could distinguish neurobrucellosis patients from normal controls. Our data offered perspectives for diagnosis and treatment for neurobrucellosis.

The NADPARK study: A randomized phase I trial of nicotinamide riboside supplementation in Parkinson’s disease

We conducted a double-blinded phase I clinical trial to establish whether nicotinamide adenine dinucleotide (NAD) replenishment therapy, via oral intake of nicotinamide riboside (NR), is safe, augments cerebral NAD levels, and impacts cerebral metabolism in Parkinson's disease (PD). Thirty newly diagnosed, treatment-naive patients received 1,000mg NR or placebo for 30days. NR treatment was well tolerated and led to a significant, but variable, increase in cerebral NAD levels-measured by 31phosphorous magnetic resonance spectroscopy-and related metabolites in the cerebrospinal fluid. NR recipients showing increased brain NAD levels exhibited altered cerebral metabolism, measured by 18fluoro-deoxyglucose positron emission tomography, and this was associated with mild clinical improvement. NR augmented the NAD metabolome and induced transcriptional upregulation of processes related to mitochondrial, lysosomal, and proteasomal function in blood cells and/or skeletal muscle. Furthermore, NR decreased the levels of inflammatory cytokines in serum and cerebrospinal fluid. Our findings nominate NR as a potential neuroprotective therapy for PD, warranting further investigation in larger trials.

A Simple and Feasible Quantification of Metabolites in the Human Follicular Fluid Using 1H HR-MAS NMR Spectroscopy

This study presents a reliable method for the quantification of metabolite concentrations in follicular fluid with the high-resolution magic angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy and the ERETIC2 (Electronic REference To access In vivo Concentrations) based on PULCON (pulse length based concentration determination) principle. The positive effect of the HR-MAS probe technology on spectral quality and its ability to perform analyses with very low sample amounts were the most important factors of proposing this method. In evaluating the performance of the proposed method, standard creatine solutions in different concentrations containing DSS (2,2-dimethyl-2-silapentane-5-sulfonate sodium salt) as an internal reference standard were analyzed using different pulse programs (cpmgpr1d and zg30). The results obtained with the ERETIC2 were compared with the classical internal standard NMR quantification method (DSS method). The relative standard deviation (RSD) values for ERETIC2 were in the range of 0.3% - 5.7% and recovery values were calculated as minimum 90.3%, while RSD values for DSS method were in the range of 0.1% - 3.1% and recovery values were minimum 97.0%. Besides, it was observed that the metabolite concentration values calculated using the ERETIC2 procedure of follicular fluid samples obtained from the women with endometriosis and healthy controls were compatible with the values those obtained using different methodologies. The obtained results showed that the proposed quantification method based on the HR-MAS spectroscopy can easily be used in biological fluids and therefore it can be utilized as a good alternative to the internal standard method considering its accuracy and precision.