On the basis of the contribution of the gut microbiota to hypertension development, a novel strategy involving fecal microbiota transplantation (FMT) has been proposed to treat hypertension, but its efficacy has not been investigated in the clinic.

In a randomized, blinded, placebo-controlled clinical trial (2021/03-2021/12, ClinicalTrials.gov, NCT04406129), hypertensive patients were recruited from seven centers in China, and received FMT or placebo capsules orally at three visits. The patients were randomized at a 1:1 ratio in blocks of four and stratified by center by an independent statistician. The intention-to-treat principle was implemented, as all randomized participants who received at least one intervention were included. The primary outcome was the decrease in office systolic blood pressure (SBP) from baseline to the day 30 visit. Adverse events (AEs) were recorded through the 3-month follow-up to assess safety measures. Alterations in BP, the fecal microbiome, and the plasma metabolome were assessed via exploratory analyses.

This study included 124 patients (mean age 43 years, 73.4% men) who received FMT (n = 63) or placebo (n = 61) capsules. The numbers of participants who experienced AEs (13 (20.6%) vs. 9 (14.8%), p = 0.39) and the primary outcome (6.28 (11.83) vs. 5.77 (10.06) mmHg, p = 0.62) were comparable between the groups. The FMT group presented a decrease in SBP after 1 week of FMT, with a between-arm difference of - 4.34 (95% CI, - 8.1 to - 0.58; p = 0.024) mmHg, but this difference did not persist even after repeated intervention. After FMT, shifts in microbial richness and structure were identified and the abundance of the phyla Firmicutes and Bacteroidetes was altered. Decreases in the abundances of Eggerthella lenta, Erysipelatoclostridium ramosum, Anaerostipes hadrus, Gemella haemolysans, and Streptococcus vestibularis and increases in the abundances of Parabacteroides merdae, Prevotella copri, Bacteroides galacturonicus, Eubacterium sp. CAG 180, Desulfovibrio piger, Megamonas hypermegale, Collinsella stercoris, Coprococcus catus, and Allisonella histaminiformans were identified and correlated with office SBP. Those species were also correlated with responding and inversely office SBP-associated metabolites including tyrosine, glutamine, aspartate, phenylalanine, methionine, serine, sarcosine, and/or asparagine.

Safety but unsustainable BP reduction was observed in the first trial of the effects of FMT on hypertension. Additional intervention studies on specific microbes with metabolite-targeting and BP-modulating features are needed. Video Abstract.

Hypertension is a highly prevalent medical condition that occurs when blood pressure is too high, which greatly increases the risk of developing other cardiovascular diseases and is generally associated with higher rates of morbidity and mortality. Due to the silent/asymptomatic nature of hypertension, although the methods currently available to diagnose it are easy, they generally do not allow for an early diagnosis and an efficient prognosis to avoid irreversible damage in the medium or long term. In fact, an early diagnosis of hypertension would be crucial to decrease hypertension-associated mortality. Since metabolomics using NMR can provide a global measurement of various serum metabolites, it is very suitable for detecting novel biomarkers. We therefore analyzed serum metabolomic profiles among normotensive and hypertensive elderly individuals by NMR and identified new potential biomarkers for hypertension and associated diseases. We found higher levels of acetate, formate, and glycerol, and lower levels of glutamine, glycine, and sarcosine in individuals with hypertension. Therefore, these metabolites could be used for early diagnosis of hypertension to avoid comorbidities derived from hypertension and associated mortality.

Predicting preeclampsia (PE) within the first 16 weeks of gestation is difficult due to various risk factors, poorly understood causes and likely multiple pathogenic phenotypes of preeclampsia.  OBJECTIVES: In this study, we aimed to develop prediction models for early-onset preeclampsia (EPE) and late-onset preeclampsia (LPE) respectively using clinical data, metabolome and proteome analyses on plasma samples and laboratory data.

We retrospectively recruited 56 EPE, 50 LPE patients and 92 normotensive controls from three tertiary hospitals and used clinical and laboratory data in early pregnancy. Models for EPE and LPE were fitted with the use of patient' clinical, multi-omics and laboratory data.

By comparing multi-omics and laboratory test variables between EPE, LPE and healthy controls, we identified sets of differentially expressed biomarkers, including 49 and 33 metabolites, 28 and 36 proteins as well as 5 and 7 laboratory variables associated with EPE and LPE respectively. Using the random forest algorithm, we developed a prediction model using seven clinical factors, seven metabolites, five laboratory test variables. The model yielded the highest accuracy for EPE prediction with good sensitivity (87.5%, 95% confidence interval [CI]: 67.64%-97.34%) and specificity (94.1%, 95% CI: 80.32%-99.28%). We also developed a prediction model that exhibited high accuracy in separating LPE from controls (sensitivity: 66.67%, 95% CI: 43.03%-85.41%; specificity: 94.12%, 95% CI: 80.32%-99.28%) using seven clinical factors, five metabolites and eight proteins.

Our study has identified a set of significant omics and laboratory features for PE prediction. The established models yielded high prediction performance for preeclampsia risk from clinical, multi-omics and laboratory information.

Differences in dietary protein have been associated with stroke risk, with possible heterogeneity in associations by stroke type or food sources of protein.

We examined the associations of individual dietary amino acids, as the constituents of dietary protein, with risks of ischemic, hemorrhagic, and total stroke.

We analyzed data from 73,830 females in the Nurses' Health Study (1984-2012), 92,333 females in the Nurses' Health Study II (1991-2013), and 43,268 males in the Health Professionals Follow-Up Study (1986-2016). Dietary intakes of 22 (20 standard and 2 nonstandard) amino acids were assessed using validated food frequency questionnaires, administered typically every 4 y. Multivariable-adjusted Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of ischemic, hemorrhagic, and total stroke in relation to the energy-adjusted intakes of individual amino acids.

During a mean follow-up of 23.7 y, 3058 ischemic, 872 hemorrhagic, and 5997 total stroke cases were documented. After correction for multiple testing, lower risks of ischemic stroke were observed with higher intakes of glutamine (HR per 1 standard deviation higher: 0.94, 95% CI: 0.90, 0.98, P = 0.004) and proline (0.94, 0.90, 0.98, P = 0.005). The associations remained directionally consistent across sensitivity analyses but attenuated upon mutual adjustment. All other amino acids, including branched-chain amino acids, were not significantly associated with ischemic stroke. For hemorrhagic stroke, no significant associations were observed for any of the amino acids. For total stroke, inverse associations were also observed for both glutamine (0.94, 0.91-0.97, P < 0.001) and proline (0.96, 0.93-0.99, P = 0.004). In terms of dietary sources, glutamine was most strongly correlated with plant protein and whole grains, whereas proline was most strongly correlated with dairy protein and dairy products.

Higher intakes of glutamine and proline were associated with lower risks of ischemic and total stroke.

Obesity and metabolic dysfunction are associated with pulmonary vascular remodeling, yet molecular mechanisms remain poorly understood. We sought to study trans-right ventricular (RV) metabolite gradients to elucidate potential molecular pathways operant among individuals with obesity and pulmonary hypertension. In this study, 38 individuals with obesity (mean age 58 years, 68% women, average BMI 36.6 kg/m2) underwent invasive right heart catheterization. Multi-site blood sampling from the superior vena cava and pulmonary artery was performed to assess trans-RV gradients, with targeted metabolite profiling using liquid chromatography-mass spectrometry. We found 56 metabolites with significant trans-RV gradients (FDR q < 0.05), including intermediates of fatty acid oxidation, the tricarboxylic acid cycle, and nucleotide metabolism. Further, trans-RV gradients in lipid and purine metabolism were associated with BMI and related cardiometabolic traits, such as waist circumference, insulin resistance, and serum lipids. Finally, differential levels of bile acids, intermediates of lipid peroxidation, and nucleotide metabolism across the RV were associated with pulmonary hypertension. In conclusion, trans-RV metabolite gradients among individuals with obesity reveal alterations in metabolites representative of molecular pathways such as fatty acid oxidation, and others correlated with cardiometabolic traits and/or pulmonary hypertension, including orotic acid, bile acids, and acylcarnitines.

Amino acids are fundamental in several metabolic processes, and their levels can reflect metabolism impairments that contribute to obesity and related diseases. Our objective was to identify a urinary amino acid fingerprint in obese and overweight children in prepuberty and to correlate this profile with cardiometabolic alterations.

The study included 110 children, boys and girls aged 9-10 years, they were classified according to their BMI-for-age (Body Mass Index for age) into three groups: normal weight (NW) (n = 45), overweight (OW) (n = 21), and obese (OB) (n = 44). The 12-h urine samples were analyzed by LC-MS/MS to quantify 47 amino acids using the Amino Acids Analysis Kit (Zivak®, Turkey), values were corrected by creatinine concentration. Anthropometric measurements, cardiovascular parameters, and biochemical profiles were assessed following standard protocols.

When compared to NW, anthropometric measures, systolic and diastolic blood pressure, and serum uric acid levels were progressively elevated in the OW and OB groups. The OB group was characterized by elevated alpha-aminoadipic acid, asparagine, cystathionine, 1-methyl-histidine, serine, tryptophan, phenylalanine, and tyrosine. In contrast, the OW group presented the most expressive levels of glutamine, alpha-diaminopimelic, and sarcosine.

Our findings indicate that obese and overweight children exhibit a particular urinary amino acid fingerprint which is similar to that reported in studies with plasma. The altered amino acids, particularly tyrosine, are frequently associated with impairments in glucose homeostasis, insulin resistance, and diabetes mellitus type 2. Potential mechanisms for increasing the levels of these amino acids in excess of weight may include enhanced protein degradation and impaired oxidative metabolism.

Recent research has extensively explored the critical role of energy metabolism in shaping the inflammatory response and polarization of macrophages in obesity. This rapidly growing field emphasizes the need to understand the connection between metabolic processes that support macrophage polarization in obesity. Although most published research in this area has focused on glucose and fatty acids, how the flux through other metabolic pathways (such as ketone and amino acid oxidation) in macrophages is altered in obesity is not well defined. This review summarizes the main alterations in uptake, storage, and oxidation of oxidative substrates (glucose, fatty acids, ketone bodies, and amino acids) in macrophages and how these alterations are linked to macrophage polarization and contribution to augmented inflammatory markers in obesity. The review also discusses how oxidative substrates could modulate macrophage energy metabolism and inflammatory responses via feeding into other nonoxidative pathways (such as the pentose phosphate pathway, triacylglycerol synthesis/accumulation), via acting as signalling molecules, or via mediating post-translational modifications (such as O-GlcNAcylation or β-hydroxybutyrylation). The review also identifies several critical unanswered questions regarding the characteristics (functional and metabolic) of macrophages from different origins (adipose tissue, skeletal muscle, bone marrow) in obesity and how these characteristics contribute to early vs late phases of obesity. We also identified a number of new therapeutic targets that could be evaluated in future investigations. Targeting macrophage metabolism in obesity is an exciting and active area of research with significant potential to help identify new treatments to limit the detrimental effects of inflammation in obesity.

Salt sensitivity of blood pressure (SSBP) is an important risk factor for essential hypertension and cardiovascular diseases, and its metabolic mechanisms remain poorly understood. This study aimed to identify SSBP-associated metabolic biomarkers and investigate their potential mediating role in the SSBP-hypertension pathophysiology.

Based on the Systematic Epidemiological Study of Salt Sensitivity (EpiSS) conducted in 2014-2016, we performed a case-control study involving 54 matched pairs of participants classified as salt-sensitive or salt-resistant with targeted metabolomics detected. Multivariable logistic regression analyses were conducted to assess the metabolites associations with SSBP and hypertension. The diagnostic performance of the model was evaluated using the receiver operating characteristic curve (ROC) analysis yielded an area under the curve (AUC) value, sensitivity, and specificity. Furthermore, the potential mediating effects of targeted metabolites on the relationship between SSBP and essential hypertension were explored.

Three metabolites demonstrated significant SSBP associations: L-Glutamine (OR = 0.998; 95% CI: 0.997, 0.999), PC (16:1/14:0) (OR = 1.039; 95% CI: 1.003, 1.077), and ChE (22:4) (OR = 1.115; 95% CI: 1.002, 1.240). Among them, L-Glutamine demonstrated the highest diagnostic efficiency for SSBP (AUC = 0.766; 95% CI: 0.677, 0.855). The combined model of the three metabolites slightly improved diagnostic efficiency (AUC = 0.788; 95% CI: 0.703, 0.874). L-Glutamine and Cer (d18:0/24:1) were identified as potential protective factors against essential hypertension (p < 0.05). Mediation analyses further indicated that L-Glutamine partially mediated the relationship between SSBP and essential hypertension, demonstrating a suppressive effect.

This study identified L-Glutamine as both a diagnostic biomarker for SSBP and a metabolic modulator attenuating hypertension risk, providing insights for early SSBP screening and the pathways governing SSBP progression to overt hypertension.

COVID-19 vaccines are crucial in reducing SARS-CoV-2 transmission and severe health outcomes. Despite widespread administration, their long-term systemic effects on human metabolism remain inadequately understood. This longitudinal study aims to evaluate IgG responses, 34 cytokines, 112 lipoproteins, and 21 low-molecular-weight metabolites in 33 individuals receiving two to four COVID-19 vaccine doses. Changes in metabolic profiles for the first 16 days post each dose of vaccine, and up to 480 days post-initial dose, were compared to baseline (before vaccination). Additionally, metabolic profiles of vaccinated participants were compared to a reference cohort of unvaccinated individuals without prior exposure to SARS-CoV-2 infection (controls) and SARS-CoV-2 cases. Positive IgG responses were observed in 78.8% (N = 26) of participants after the first dose, reaching 100% with subsequent doses. The most common side effects were localized pain at the injection site and "flu-like" symptoms, reported by > 50% of participants. Systemic side effects, e.g., sore lymph nodes, fatigue, and brain fog, were reported but showed no significant correlations to IgG responses. Transient temporal changes were observed for cytokine IP10 (CXCL10) and glutamic acid around the third vaccine dose. Compared to the reference cohort, 497 vaccinated samples (95.0%) had profiles similar to the controls, while the remaining 26 samples with prior infection exposures were similar to mild cases of SARS-CooV-2 infection. In conclusion, COVID-19 vaccination did not induce lasting changes in inflammatory and metabolic responses, nor did it induce changes similar to mild cases of SARS-CoV-2 infection. This supports the metabolic safety of the vaccine and contributes to increased vaccine confidence. KEY MESSAGES: Minimal changes in inflammatory/metabolic markers up to 480 days post-vaccination. Transient increase in IP10 (CXCL10) and glutamic acid around the third dose. Post-vaccination IgG response did not alter metabolic profiles like SARS-CoV-2 cases. Our findings provide insights into the safety of repeated COVID-19 vaccinations.

Glutamine availability may be reduced in chronic diseases, such as type 2 diabetes mellitus (T2DM)-induced by obesity. Herein, the antioxidant, anti-inflammatory and lipid metabolism effects of chronic oral glutamine supplementation in its free and dipeptide form were assessed in ob/ob mice. Adult male C57BL/6J ob/ob mice were supplemented with L-alanyl-L-glutamine (DIP) or free L-glutamine (GLN) in the drinking water for 40 days, whilst C57BL/6J Wild-type lean (WT) and control ob/ob mice (CTRL) received fresh water only. Plasma and tissue (skeletal muscle and liver) glutamine levels, and insulin resistance parameters (e.g., GTT, ITT, insulin) were determined. Oxidative stress (e.g., GSH system, Nrf2 translocation), inflammatory (e.g., NFkB translocation, TNF-α gene expression) and lipid metabolism parameters (e.g., plasma and liver triglyceride levels, SRBP-1, FAS, ACC, and ChRBP gene expression) were also analyzed. CTRL ob/ob mice showed lower glutamine levels in plasma and tissue, as well as increased insulin resistance and fat in the liver. Conversely, chronic DIP supplementation restored glutamine levels in plasma and tissues, improved glucose homeostasis and reduced plasma and liver lipid levels. Also, Nrf2 restoration, reduced NFkB translocation, and lower TNF-α gene expression was observed in the DIP group. Interestingly, chronic free GLN only increased muscle glutamine stores but reduced overall insulin resistance, and attenuated plasma and liver lipid metabolic biomarkers. The results presented herein indicate that restoration of body glutamine levels reduces oxidative stress and inflammation in obese and T2DM ob/ob mice. This effect attenuated hepatic lipid metabolic changes observed in obesity.

This study aimed to explore the possible bidirectional interrelations between fructose-induced metabolic syndrome (MS) and apical periodontitis (AP).

Twenty-eight male Wistar rats were distributed into four groups (n = 7, per group): Control (C), AP, Fructose Consumption (FRUT) and Fructose Consumption and AP (FRUT+AP). The rats in groups C and AP received filtered water, while those in groups FRUT and FRUT+AP received a 20% fructose solution mixed with water to induce MS. The groups AP and FRUT+AP had the pulp of their right mandibular first molar exposed to induce AP. Food consumption, murinometric measurements, blood glucose levels and glucose tolerance were monitored. Fifty-six days after the start of the experiment, the animals were euthanized, and serum samples were collected for metabolomic analysis. Mandibles, livers and right kidneys were also collected. The area and volume of the periapical lesions were calculated using micro-computed tomography. Histopathological evaluation was performed. Kruskal-Wallis followed by the Student-Newman-Keuls or Mann-Whitney tests and one-way anova followed by Tukey's or Independent t-test were used for non-parametric and parametric data, respectively (p < .05). Multivariate analysis and variable importance in projection score were applied to assess metabolite profile differences among groups (p < .05).

FRUT and FRUT+AP groups showed significantly increased fluid intake, body mass, abdominal circumference, blood glucose levels, liver weight and visceral fat weight (p < .05), indicating the development of MS. The analyses of the metabolite profile suggest increasing glucose, histidine, lactate, fatty acid and phenylalanine in the FRUT+AP group. There were no significant differences in volume and area of periapical lesions in micro-CT analyses (p = .1048 and p = .7494, respectively). Histopathological analysis of the hemimandibles demonstrated areas of inflammatory response, necrosis and microabscess in the periapical region. Hepatic histopathological observations indicated notable differences in cell appearance, with the FRUT and FRUT+AP groups showing signs of microsteatosis. Kidney analysis revealed Bowman's space dilation in the FRUT and AP groups, while the FRUT+AP group exhibited retracted Bowman's space, suggesting a possible alteration in renal filtration capacity.

MS had no impact on the progression of AP in rats. However, AP exacerbated the systemic state affected by MS, with changes in liver and kidney tissues and metabolite levels.

Inhaling aerosols from electronic nicotine delivery systems, such as e-cigarettes (e-cigs), may pose health risks beyond those caused by nicotine intake. Exposure to e-cig aerosols can lead to the release of exosomes and metabolites into the bloodstream, potentially affecting mitochondrial physiology across the body, leading to chronic inflammatory diseases. In this study we assessed the effects of e-cig use by young healthy human subjects on the circulating exosome profile and markers of cell stress, and also defined the effects of e-cig user plasma on mitochondrial function in endothelial cells (EA. Hy 926) and epithelial cells (A549) via adoptive transfer. E-cig users had altered plasma exosome profiles, with significantly increased levels of cell free mitochondrial DNA (mtDNA), protein carbonyls, and 4-HNE relative to non-users. Plasma from e-cig users decreased maximal mitochondrial respiration and spare capacity of cells, while also increasing metabolic stress, as evidenced by changes in mitochondrial phenotype from basal to stressed in both endothelial and epithelial cells, which was corroborated by electron microscopy demonstrating structural changes in mitochondria. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) levels significantly increased in e-cig plasma-subjected cells. Overall, we identified alterations in plasma exosome profiles and increased markers of mitochondrial stress in e-cig users and evidence that circulating factors within plasma from e-cig users drives metabolic stress in endothelial and epithelial cells. Our results imply that e-cig use adversely affects mitochondrial function, leading to stress and potentially chronic inflammation across the body.

Malignant brain tumors are among the most lethal cancers. Recent studies emphasized the crucial involvement of the immune system, especially T cells, in driving tumor progression and influencing patient outcomes. The emerging field of immunometabolism has shown that metabolic pathways play a pivotal role in regulating immune responses within the tumor microenvironment. This study aims to clarify the relationships between specific T cell phenotypes, circulating metabolites, and malignant brain tumors.

We utilized a multiple mendelian randomization approach to investigate the associations between T cell phenotypes and malignant brain tumors, as well as the role of plasma metabolites in mediating these interactions. Instrumental variables were selected based on stringent criteria, and multiple mendelian randomization methods were utilized to identify causal pathways and metabolites potentially mediating these effects.

Our analysis identified significant associations between seven distinct T cell phenotypes, including various CD8 + and regulatory T cell subsets, and the presence of malignant brain tumors. We also identified 87 plasma metabolites correlated with these tumors. Notably, metabolites such as octadecanedioylcarnitine (C18-DC) and eicosanedioate (C20-DC) were implicated in modulating the risk of developing malignant brain tumors. Furthermore, metabolites such as 5-dodecenoate (12:1n7) and arachidonate (20:4n6) were found to influence tumor risk, particularly in relation to CD28 - CD8 + T cells.

The study identifies key T cell phenotypes and plasma metabolites involved in the pathogenesis of malignant brain tumors, offering potential biomarkers and therapeutic targets for future interventions.

We aimed to evaluate the incremental predictive value of metabolomic biomarkers for assessing the 10-year risk of type 2 diabetes when added to the clinical Cambridge Diabetes Risk Score (CDRS).

We utilized 86,232 UK Biobank (UKB) participants (recruited between 13 March 2006 and 1 October 2010) for model derivation and internal validation. Additionally, we included 4383 participants from the German ESTHER cohort (recruited between 1 July 2000 and 30 June 2002 for external validation). Participants were followed up for 10 years to assess the incidence of type 2 diabetes. A total of 249 NMR-derived metabolites were quantified using nuclear magnetic resonance (NMR) spectroscopy. Metabolites were selected with LASSO regression and model performance was evaluated with Harrell's C-index.

11 metabolomic biomarkers, including glycolysis related metabolites, ketone bodies, amino acids, and lipids, were selected. In internal validation within the UKB, adding these metabolites significantly increased the C-index (95% confidence interval (95% CI)) of the clinical CDRS from 0.815 (0.800, 0.829) to 0.834 (0.820, 0.847) and the continuous net reclassification index (NRI) with 95% CI was 39.8% (34.6%, 45.0%). External validation in the ESTHER cohort showed a comparable statistically significant C-index increase from 0.770 (0.750, 0.791) to 0.798 (0.779, 0.817) and a continuous NRI of 33.8% (26.4%, 41.2%). A concise model with 4 instead of 11 metabolites yielded similar results.

Adding 11 metabolites to the clinical CDRS led to a novel type 2 diabetes prediction model, we called UK Biobank Diabetes Risk Score (UKB-DRS), substantially outperformed the clinical CDRS. The concise version with 4 metabolites performed comparably. As only very few clinical information and a blood sample are needed for the UKB-DRS, and as high-throughput NMR metabolomics are becoming increasingly available at low costs, these models have considerable potential for routine clinical application in diabetes risk assessment.

The ESTHER study was funded by grants from the Baden-Württemberg state Ministry of Science, Research and Arts (Stuttgart, Germany), the Federal Ministry of Education and Research (Berlin, Germany), the Federal Ministry of Family Affairs, Senior Citizens, Women and Youth (Berlin, Germany), and the Saarland State Ministry of Health, Social Affairs, Women and the Family (Saarbrücken, Germany). The UK Biobank project was established through collaboration between various entities including the Wellcome Trust, the Medical Research Council, Department of Health, Scottish Government, and the Northwest Regional Development Agency. Additional funding was provided by the Welsh Assembly Government, British Heart Foundation, Cancer Research UK, and Diabetes UK, with support from the National Health Service (NHS). The German Diabetes Center is funded by the German Federal Ministry of Health (Berlin, Germany) and the Ministry of Culture and Science of the state North Rhine-Westphalia (Düsseldorf, Germany) and receives additional funding from the German Federal Ministry of Education and Research (BMBF) through the German Center for Diabetes Research (DZD e.V.).

Metabolic dysregulation is closely associated with coronary artery diseases (CAD). Exploring the relationship between metabolites and CAD is helpful in identifying changes in energy metabolism during disease progression.

We use Mendelian Randomization (MR) analysis to assess the relationships between 275 serum metabolites and CAD such as angina pectoris, post-myocardial infarction complications, coronary atherosclerosis, myocardial infarction (MI), and unstable angina pectoris (UA). The inverse variance-weighted method (IVW) served as the primary approach for causal analysis, with MR-Egger and weighted median (WM) as supplementary methods. Sensitivity analyses were conducted to assess heterogeneity and multiple effects. We also analyzed potentially related metabolic pathways.We identified causal relationships between 42 known metabolites and CAD. Among them, the genetic susceptibility to elevated levels of amino acid Isobutyrylcarnitine is associated with an increased risk of coronary artery atherosclerosis; but it provides protection against the development of MI. Genetic susceptibility to elevated levels of fatty acids Stearate, Caprylate is associated with higher risk of angina pectoris, while Threonate has a protective effect in the development of angina; Stearate is associated with an increased risk of UA, whereas higher levels of the lipids Choline, 1-arachidonoylglycerophosphoinositol∗, Hexadecanedioate, Tetradecanedioate play a protective role in UA.Metabolic pathway analysis identified 6 pathways that may be associated with CAD.

We identified causal relationships between 42 serum metabolites and CAD. Specifically, changes in metabolites such as Isobutyrylcarnitine, Caprylate, and Stearate were associated with risks of CAD. These findings provide new insights into the metabolic mechanisms of CAD.

The left and right ventricles of the human heart are functionally and developmentally distinct such that genetic or acquired insults can cause dysfunction in one or both ventricles resulting in heart failure. To better understand ventricle-specific molecular changes influencing heart failure development, we first performed unbiased quantitative mass spectrometry on pre-mortem non-diseased human myocardium to compare the metabolome and proteome between the normal left and right ventricles. Constituents of gluconeogenesis, glycolysis, lipogenesis, lipolysis, fatty acid catabolism, the citrate cycle and oxidative phosphorylation were down-regulated in the left ventricle, while glycogenesis, pyruvate and ketone metabolism were up-regulated. Inter-ventricular significance of these metabolic pathways was then found to be diminished within end-stage dilated cardiomyopathy and ischaemic cardiomyopathy, while heart failure-associated pathways were increased in the left ventricle relative to the right within ischaemic cardiomyopathy, such as fluid sheer-stress, increased glutamine-glutamate ratio, and down-regulation of contractile proteins, indicating a left ventricular pathological bias.

Metabolomics has come to the fore as an efficient tool in the search for biomarkers that are critical for precision health approaches and improved diagnostics. This review will outline recent advances in biomarker discovery based on metabolomics, focusing on metabolomics biomarkers reported in cancer, neurodegenerative disorders, cardiovascular diseases, and metabolic health. In cancer, metabolomics provides evidence for unique oncometabolites that are important for early disease detection and monitoring of treatment responses. Metabolite profiling for conditions such as neurodegenerative and mental health disorders can offer early diagnosis and mechanisms into the disease especially in Alzheimer's and Parkinson's diseases. In addition to these, lipid biomarkers and other metabolites relating to cardiovascular and metabolic disorders are promising for patient stratification and personalized treatment. The gut microbiome and environmental exposure also feature among the influential factors in biomarker discovery because they sculpt individual metabolic profiles, impacting overall health. Further, we discuss technological advances in metabolomics, current clinical applications, and the challenges faced by metabolomics biomarker validation toward precision medicine. Finally, this review discusses future opportunities regarding the integration of metabolomics into routine healthcare to enable preventive and personalized approaches.

Cardiovascular disease is the most common cause of mortality globally, accounting for approximately one out of three deaths. The main underlying pathology is atherosclerosis, a dyslipidemia-driven, chronic inflammatory disease. The interplay between immune cells and non-immune cells is of great importance in the complex process of atherogenesis. During atheroprogression, intracellular metabolic pathways, such as amino acid metabolism, are master switches of immune cell function. Autophagy, an important stress survival mechanism involved in maintaining (immune) cell homeostasis, is crucial during the development of atherosclerosis and is strongly regulated by the availability of amino acids. In this review, we focus on the interplay between amino acids, especially L-leucine, L-arginine, and L-glutamine, and autophagy during atherosclerosis development and progression, highlighting potential therapeutic perspectives.

Metabolic dysregulation, including perturbed glutamine-glutamate homeostasis, is common among patients with cardiovascular diseases, but the underlying mechanisms remain largely unknown. Using the human MESA cohort, here we show that plasma glutamine-glutamate ratio is an independent risk factor for carotid plaque progression. Mice deficient in glutaminase-2 (Gls2), the enzyme that mediates hepatic glutaminolysis, developed accelerated atherosclerosis and susceptibility to catastrophic cardiac events, while Gls2 overexpression partially protected from disease progression. High-throughput transcriptional profiling and high-resolution structural biology imaging of aortas showed that Gls2 deficiency perturbed extracellular matrix composition and increased vessel stiffness. This results from an imbalance of glutamine- and glutamate-dependent cross-linked proteins within atherosclerotic lesions and cellular remodeling of plaques. Thus, hepatic glutaminolysis functions as a potent regulator of glutamine homeostasis, which affects the aortic wall structure during atherosclerotic plaque progression.

Preeclampsia, a pregnancy-specific syndrome, poses substantial risks to maternal and neonatal health, particularly in cases with severe features. Our study focuses on evaluating the impact of low molecular weight metabolites on the intricate mechanisms and pathways involved in the pathophysiology of preeclampsia when severe features are present. We aim to pinpoint the distinct metabolomic profile in maternal plasma during pregnancies affected by hypertensive disorders and to correlate the metabolite levels with the clinical characteristics of the study cohort. A total of 173 plasma samples were collected, comprising 36 healthy pregnant women (HP), 52 patients with gestational hypertension (GH), 43 with preeclampsia without (PE-), and 42 with severe features (PE+). Nuclear magnetic resonance spectroscopy and metabolite identification were conducted to establish the metabolomic profiles. Univariate and chemometric analyses were conducted using MetaboAnalyst, and correlations were performed using GraphPad Prism. Our study unveils distinct metabolomic profiles differentiating HP women, patients featuring GH, and patients with PE-and PE+. Our analysis highlights an increase in acetate, N,N-dimethylglycine, glutamine, alanine, valine, and creatine levels in the PE+ group compared to the HP and GH groups. The PE+ group exhibited higher concentrations of N,N-dimethylglycine, glutamine, alanine, and valine compared to the PE-group. Moreover, elevated levels of specific metabolites, including N,N-dimethylglycine, alanine, and valine, were associated with increased blood pressure, worse obstetric outcomes, and poorer end-organ function, particularly renal and hepatic damage. Metabolomic analysis of PE+ individuals indicates heightened disturbances in nitrogen metabolism, methionine, and urea cycles. Additionally, the exacerbated metabolic disturbance may have disclosed renal impairment and hepatic dysfunction, evidenced by elevated levels of creatine and alanine. These findings not only contribute novel insights but also provide a more comprehensive understanding of the pathophysiological mechanisms at play in cases of PE+.

Elevated concentrations of amino acids (AAs) are commonly observed in patients with nonalcoholic fatty liver disease (NAFLD). Individuals with hypopituitarism (HP) are at a heightened risk of developing NAFLD due to factors such as visceral obesity, increased insulin resistance (IR), and disturbances in lipid metabolism. However, the changes in AAs concentrations associated with HP remain poorly understood. Therefore, our study aimed to investigate whether individuals with HP, who were not receiving growth hormone replacement therapy (GHRT), exhibited altered AAs compared to controls (CTs), and whether these AAs were associated with IR, the presence of NAFLD, and the Metabolic Syndrome (MetS) score. The AAs profiles of 133 young males with HP (age: 24.5 ± 5.9; 57 with NAFLD and 76 without NAFLD) and 90 age and BMI-matched CTs were analyzed using untargeted metabolomics. The results revealed that most AAs were found to be elevated in subjects with HPs compared to CTs. Glutamate, glutamine, norleucine, and branched-chain amino acids (BCAAs) (leucine and valine) were correlated with the homeostasis model assessment of insulin resistance (HOMA-IR), with glutamate and norleucine showing independent linkage. Glutamate and proline levels were specifically associated with MetS score, while alanine and proline linked to NAFLD. Given that elevated glutamate and BCAAs levels have higher prevalence of NAFLD, we hypothesized that the changes in AAs observed in HPs may be attributed to the impact of NAFLD and IR.

Coronary artery disease (CAD) remains a leading cause of death worldwide and imposes a substantial socioeconomic burden on healthcare. Improving risk stratification in clinical practice could help to combat this burden. As amino acids are biologically active metabolites whose involvement in CAD remains largely unknown, this study investigated associations between circulating amino acid levels and CAD phenotypes. A high-coverage quantitative liquid chromatography-mass spectrometry approach was applied to acquire the serum amino acids profile of age- and sex-coarsened-matched patients with CAD (n = 46, 66.9 years, 74.7% male) and healthy individuals (n = 120, 67.4 years, 74.7% male) from the COmPLETE study. Multiple linear regressions were performed to investigate associations between amino acid levels and (a) the health status (CAD vs. healthy), (b) the number of affected coronary arteries, or (c) the left ventricular ejection fraction. Regressions were adjusted for age, sex, daily physical activity, sampling, and fasting time. Urea cycle amino acids (ornithine, citrulline, homocitrulline, aspartate, and arginine) were significantly and negatively associated with CAD, the number of affected coronary arteries, and the left ventricular ejection fraction. Lysine, histidine, and the glutamine/glutamate ratio were also significantly and negatively associated with the CAD phenotypes. Overall, patients with CAD displayed lower levels of urea cycle amino acids, highlighting a potential role for urea cycle amino acid profiling in cardiovascular risk stratification.Trial registrationThe study was registered on https://www.clinicaltrials.gov (NCT03986892) on June 5, 2019.

This study aims to conduct a comprehensive investigation of the serum amino acid profiles of individuals with type 2 diabetes (T2D) and its related complications.

Patients with T2D were enrolled in this study. Sixteen kinds of common amino acids in the fasting circulating were assessed through liquid chromatography-mass spectrometry (LC-MS). Subsequently, correlation, regression analyses, and receiver operating characteristic (ROC) curves were conducted to assess the associations between amino acids and clinical indicators.

Thirteen different kinds of amino acids were identified in diabetic patients, as compared with normal controls. The Glutamine/Glutamate (Gln/Glu) ratio was negatively correlated with BMI, HbA1c, serum uric acid, and the triglyceride-glucose (TyG) index, while it was positively correlated with HDL-C. Logistic regression analyses indicated that Gln/Glu was a consistent protective factor for both T2D (OR = 0.65, 95% CI 0.50-0.86) and obesity (OR = 0.79, 95% CI 0.66-0.96). The ROC curves demonstrated that Gln/Glu, proline, valine, and leucine provided effective predictions for diabetes risk, with Gln/Glu exhibiting the highest AUC [0.767 (0.678-0.856)]. In patients with T2D, Gln was the only amino acid that displayed a negative correlation with HbA1c (r = -0.228, p = 0.017). Furthermore, HOMA-β exhibited a negative correlation with Glu (r = -0.301, p = 0.003) but a positive correlation with Gln/Glu (r = 0.245, p = 0.017). Notably, logistic regression analyses revealed an inverse correlation of Gln/Glu with the risk of diabetic kidney disease (OR = 0.74, 95% CI 0.55-0.98) and a positive association with the risk of diabetic retinopathy (OR = 1.53, 95% CI 1.08-2.15).

The Gln/Glu ratio exhibited a significant association with diabetes, common metabolic parameters, and diabetic complications. These findings shed light on the pivotal role of Gln metabolism in T2D and its associated complications.

Mental health disorders are one of the most important and increasing health problems in the youth of today's societies. Some dietary intake and body mass status are factors that affect mental health. This study aimed to investigate the relationship between the intake of branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) and anthropometric and dietary inflammatory indices with mental health, including depression, anxiety, and stress.

In this case-control study, the data of 138 teenage girls aged 13-18 years were collected. Three-day 24-hour food recall and standard anthropometric methods were used to calculate the dietary inflammation intake score of normal and energy-adjusted diets. Mental health disorders were diagnosed by the DASS-21 questionnaire. Statistical analysis used Student's t-test, correlation, and multiple regression were used to analyze the data based on the study's statistical requirements.

Based on the findings, 59 (42%) of the girls had mental disorders, and 79 (58%) were healthy. The average weight of stressed people was significantly higher than that of healthy people, and the BMI of anxious people was significantly higher than that of nonanxious people (P < 0.05). A significant positive correlation was found between stress and weight and energy intake. Additionally, there was a significant negative correlation between BCAAs and mental health. The average intake of BCAAs was significantly lower in patients (P = 0.01). The trend analysis showed significantly lower BCAA levels among the 4th quartile of mental disorders. No significant relationship was observed between DII, AAA, and anthropometric indices. After adjustment of the results, no relationship was observed between mental health and the studied factors.

BCAA might be related to mental health. Further studies in different age and sex groups are highly recommended.

The Fufang Xueshuantong capsule (FXT) has significant preventive and therapeutic effects on diabetic retinopathy(DR), but the compatibility of its active components remains to be thoroughly explored. In this study, a zebrafish diabetic retinopathy model was established using high-mixed sugars, and the optimal ratios of notoginseng total saponins, total salvianolic acid, astragaloside, and harpagide were selected through orthogonal experiments. Furthermore, we used UPLC-QqQ/MS to detect the changes in amino acid content of DR zebrafish tissues after administration of FXT and its compatible formula to analyze the effects of FXT and its compatible formula on amino acid metabolites. The results showed that the final compatibility ratios of the components were 8: 5: 1: 6.6 by comprehensive evaluation of the indicators. FXT and its compatibility formula had beneficial effects on retinal vasodilatation, lipid accumulation in the liver, total glucose, and VEGF levels in DR zebrafish, and all of them could call back some amino acid levels in DR zebrafish. In this research, we determined the compatible formulation of the active ingredients in the FXT and investigated their efficacy in DR zebrafish for further clinical applications.

Congenital heart disease (CHD) is the most common congenital anomaly, representing a significant global disease burden. Limitations exist in our understanding of aetiology, diagnostic methodology and screening, with metabolomics offering promise in addressing these.

To evaluate maternal metabolomics and lipidomics in prediction and risk factor identification for childhood CHD.

We performed an observational study in mothers of children with CHD following pregnancy, using untargeted plasma metabolomics and lipidomics by ultrahigh performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). 190 cases (157 mothers of children with structural CHD (sCHD); 33 mothers of children with genetic CHD (gCHD)) from the children OMACp cohort and 162 controls from the ALSPAC cohort were analysed. CHD diagnoses were stratified by severity and clinical classifications. Univariate, exploratory and supervised chemometric methods were used to identify metabolites and lipids distinguishing cases and controls, alongside predictive modelling.

499 metabolites and lipids were annotated and used to build PLS-DA and SO-CovSel-LDA predictive models to accurately distinguish sCHD and control groups. The best performing model had an sCHD test set mean accuracy of 94.74% (sCHD test group sensitivity 93.33%; specificity 96.00%) utilising only 11 analytes. Similar test performances were seen for gCHD. Across best performing models, 37 analytes contributed to performance including amino acids, lipids, and nucleotides.

Here, maternal metabolomic and lipidomic analysis has facilitated the development of sensitive risk prediction models classifying mothers of children with CHD. Metabolites and lipids identified offer promise for maternal risk factor profiling, and understanding of CHD pathogenesis in the future.

Glutamine and glutamate are interconverted by several enzymes and alterations in this metabolic cycle are linked to cardiometabolic traits. Herein, we show that obesity-associated insulin resistance is characterized by decreased plasma and white adipose tissue glutamine-to-glutamate ratios. We couple these stoichiometric changes to perturbed fat cell glutaminase and glutamine synthase messenger RNA and protein abundance, which together promote glutaminolysis. In human white adipocytes, reductions in glutaminase activity promote aerobic glycolysis and mitochondrial oxidative capacity via increases in hypoxia-inducible factor 1α abundance, lactate levels and p38 mitogen-activated protein kinase signalling. Systemic glutaminase inhibition in male and female mice, or genetically in adipocytes of male mice, triggers the activation of thermogenic gene programs in inguinal adipocytes. Consequently, the knockout mice display higher energy expenditure and improved glucose tolerance compared to control littermates, even under high-fat diet conditions. Altogether, our findings highlight white adipocyte glutamine turnover as an important determinant of energy expenditure and metabolic health.

Metabolomics studies have identified various metabolic markers associated with stroke risk, yet much uncertainty persists regarding heterogeneity in these associations between different stroke subtypes. We aimed to examine metabolic profiles associated with incident stroke and its subtypes in Chinese adults.

We performed a nested case-control study within the Dongfeng-Tongji cohort, including 1029 and 266 incident cases of ischemic stroke (IS) and hemorrhagic stroke (HS), respectively, with a mean follow-up period of 6.1±2.3 years. Fifty-five metabolites in fasting plasma were measured by ultra-high-performance liquid chromatography-mass spectrometry. We examined the associations of metabolites with the risks of total stroke, IS, and HS, with a focus on the comparison of associations of plasma metabolite with IS and HS, using conditional logistic regression. We found that increased levels of asymmetrical/symmetrical dimethylarginine and glutamate were significantly associated with elevated risk of total stroke (odds ratios and 95%, 1.20 [1.08-1.34] and 1.22 [1.09-1.36], respectively; both Benjamini-Hochberg-adjusted P <0.05). When examining stroke subtypes, asymmetrical/symmetrical dimethylarginine was nominally associated with both IS and HS (odds ratios [95% CIs]: 1.16 [1.03-1.31] and 1.39 [1.07-1.81], respectively), while glutamate was associated with only IS (odds ratios [95% CI]: 1.26 [1.11-1.43]). The associations of glutamate with IS risk were significantly stronger among participants with hypertension and diabetes than among those without these diseases (both P for interaction <0.05).

This study validated the positive associations of asymmetrical/symmetrical dimethylarginine and glutamate with stroke risk, mainly that of IS, in a Chinese population, and revealed a novel unanimous association of with both IS and HS. Our findings provided potential intervention targets for stroke prevention.

Insulin resistance is a common pathophysiology in patients with type 2 diabetes mellitus, cardiovascular disease, and non-alcoholic fatty liver disease. Thus, screening for the risk of insulin resistance is important to prevent disease progression. We evaluated the alanine aminotransferase/aspartate aminotransferase (ALT/AST) ratio to predict insulin resistance in the general population, regardless of comorbidities. Datasets from the 2015, 2019, and 2020 Korea National Health and Nutrition Examination Surveys were used, and the following four indices were implemented to indicate insulin resistance: fasting serum glucose, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), and β-cell function. We analyzed the degree of association between the liver enzyme profile and insulin resistance indices using Pearson's correlation coefficient and determined the associations using linear or logistic regression analysis. Accordingly, ALT levels in both sexes were positively and consistently correlated with the four aforementioned insulin resistance indices in stratification analyses based on diabetes, dyslipidemia, alcohol consumption, and obesity status. In multivariate linear regression, when comparing with ALT levels, the ALT/AST ratio exhibited superior predictive performance for fasting serum glucose and HOMA-β in Korean men and improved outcomes for all insulin resistance indices in Korean women. In this analysis that included a large community-based population, the ALT/AST ratio was a more useful predictive marker than the HOMA-IR. Regarding the predicted presence or absence of insulin resistance, the ALT/AST ratio could better predict HOMA-IR than the ALT level alone in Koreans. A simple, precise marker that represents the ALT/AST ratio could be a practical method to screen for insulin resistance in the general population, regardless of diabetes mellitus, alcohol intake, and sex.

Brown adipose tissue (BAT) is best known for thermogenesis. Rodent studies demonstrated that enhanced BAT thermogenesis is tightly associated with increased energy expenditure, reduced body weight, and improved glucose homeostasis. However, human BAT is protective against type 2 diabetes, independent of body weight. The mechanism underlying this dissociation remains unclear. Here, we report that impaired mitochondrial catabolism of branched-chain amino acids (BCAAs) in BAT, by deleting mitochondrial BCAA carriers (MBCs), caused systemic insulin resistance without affecting energy expenditure and body weight. Brown adipocytes catabolized BCAA in the mitochondria as nitrogen donors for the biosynthesis of non-essential amino acids and glutathione. Impaired mitochondrial BCAA-nitrogen flux in BAT resulted in increased oxidative stress, decreased hepatic insulin signaling, and decreased circulating BCAA-derived metabolites. A high-fat diet attenuated BCAA-nitrogen flux and metabolite synthesis in BAT, whereas cold-activated BAT enhanced the synthesis. This work uncovers a metabolite-mediated pathway through which BAT controls metabolic health beyond thermogenesis.