Obesity is associated with vitamin D (VD) deficiency and arterial stiffness. This randomized control trial assessed the effects of VD supplementation during a weight-loss program on carotid intima-media thickness (IMT) and carotid compliance in obese adolescents. Participants were randomly assigned to receive either a 12-week lifestyle program with VD supplementation (n = 13), a lifestyle program without VD supplementation (n = 13) or a control group composed of normal-weight adolescents (n = 18). Serum total and free 25-hydroxyvitamin D (25(OH)D), IMT and carotid compliance were measured before and after the trial. Insufficiency in 25(OH)D concentration was found in 73% of obese participants compared to 22% among controls. Obese adolescents had lower free 25(OH)D and displayed higher IMT but lower carotid compliance than controls. Free 25(OH)D and IMT were negatively correlated in adolescents displaying VD insufficiency at baseline. After three months, total and free 25(OH)D increased in both groups. The changes of IMT and carotid compliance were similar between groups. The changes in IMT were correlated with the changes in total 25(OH)D in obese adolescents with VD insufficiency at baseline (r = −0.59, p = 0.03). While the lifestyle program with VD supplementation did not affect carotid compliance, IMT reduction was improved in obese adolescents.

Objective: Dietary intakes must cover protein and essential amino acid (EAA) requirements. For this purpose, different methods have been developed such as the nitrogen balance method, factorial method, or AA tracer studies. However, these methods are either invasive or imprecise, and the Food and Agriculture Organization of the United Nations (FAO, 2013) recommends new methods and, in particular, metabolomics. The aim of this study is to determine total protein/EAA requirement in the plasma and urine of growing rats. Methods: 36 weanling rats were fed with diets containing 3, 5, 8, 12, 15, and 20% protein for 3 weeks. During experimentation, urine was collected using metabolic cages, and blood from the portal vein and vena was taken at the end of the experiment. Metabolomics analyses were performed using LC-MS, and the data were analyzed with a multivariate analysis model, partial least Squares (PLS) regression, and independent component-discriminant analysis (ICDA). Each discriminant metabolite identified by PLS or ICDA was tested by one-way ANOVA to evaluate the effect of diet. Results: PLS and ICDA allowed us to identify discriminating metabolites between different diet groups. Protein deficiency led to an increase in the AA catabolism enzyme systems inducing the production of breakdown metabolites in the plasma and urine. Conclusion: These results indicate that metabolites are specific for the state of EAA deficiency and sufficiency. Some types of biomarkers such as AA degradation metabolites appear to be specific candidates for protein/EAA requirement.

Prematurity is associated with a higher risk of developing short- and long-term metabolic complications. However, the concrete mechanisms are not yet fully understood. The purpose of this study was to characterize early urinary metabolic adaptations linked to preterm birth. Urine samples collected at one month of age were compared between extremely and very preterm neonates (<32 weeks gestation) (n = 45) and term newborns (n = 96). Liquid chromatography coupled to mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) techniques were both applied and analyzed independently. Univariate analysis and multivariate analyses were utilized to assess the impact of preterm birth on the metabolites identified. Multiblock analysis was further used to evaluate the effect of prematurity on biological functions. A profound impact of prematurity was observed. Both experimental groups differed in the concentrations of 240 metabolites from the LC-MS dataset and 52 from the NMR one. Multivariate analyses confirmed a significant and important separation between groups. Finally, multiblock analysis identified six major biological outcomes affected by preterm birth: nitrogen metabolism, growth, neurochemical metabolism, microbiota metabolism, cell defense, and metabolic alterations. Most of the observed variations exhibited biological plausibility and were consistent with reported health complications associated with preterm birth. In conclusion, preterm birth is linked to a specific fingerprint in the urinary metabolome, reflecting metabolic adaptations in multiple systems occurring at one month of age.

Carotid atherosclerotic stenosis (CAS) is a leading cause of ischemic stroke. Current understanding of plaque vulnerability remains largely confined to histopathological characterization. Consequently, identifying molecular determinants of plaque stability represents a major challenge to advance prevention strategies. Untargeted metabolomic analysis was performed using mass spectrometry coupled to liquid chromatography on carotid plaques removed from patients with CAS undergoing endarterectomy. To identify factors influencing plaque stability, we compared 42 asymptomatic with 30 symptomatic CAS patients. Associations between each annotated metabolite in plaques and asymptomatic CAS status were assessed using logistic regression models. Asymptomatic patients exhibited lower plasmatic levels of C-reactive protein (CRP) and higher HDL-cholesterol. Within the plaques, caffeine and its catabolites, paraxanthine and methylxanthine, were associated with plaque stability and were correlated with HDL-cholesterol. Additional plant-based diet biomarkers including N5-acetylornithine, gentisic acid, proline betaine, and homostachydrine were also associated with plaque stability. In contrast, N-methylpyridone carboxamides, reflecting niacin excess, involved in vascular inflammatory processes, were both associated with plaque vulnerability and also correlated with higher CRP. Our findings provide molecular evidence that plant-based diets, including coffee, promote carotid plaque stability, while excessive niacin intake, linked to processed foods, may be detrimental. Metabolomics offers new insights into food exposome-related vascular risk.