Novel multimetabolite prediction of walnut consumption by a urinary biomarker model in a free-living population: the PREDIMED Study

The beneficial impact of walnuts on human health has been attributed to their unique chemical composition. In order to characterize the dietary walnut fingerprinting, spot urine samples from two sets of 195 (training) and 186 (validation) individuals were analyzed by an HPLC-q-ToF-MS untargeted meta...

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Bibliographic Details
Authors: Garcia Aloy, Mar, Llorach, Rafael, Urpí Sardà, Mireia, Tulipani, Sara, Estruch Riba, Ramon, Martínez-González, Miguel Ángel, 1957-, Corella Piquer, Dolores, Fitó Colomer, Montserrat, Ros Rahola, Emilio, Salas Salvadó, Jordi, Andrés Lacueva, Ma. Cristina
Format: article
Status:Versión aceptada para publicación
Publication Date:2014
Country:España
Institution:Universidad de Barcelona
Repository:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/109055
Online Access:https://hdl.handle.net/2445/109055
Access Level:Open access
Keyword:Marcadors bioquímics
Cromatografia de líquids d'alta resolució
Cuina (Nous)
Cuina mediterrània
Metabolisme
Malalties cardiovasculars
Orina
Biochemical markers
High performance liquid chromatography
Cooking (Nuts)
Mediterranean cooking
Metabolism
Cardiovascular diseases
Urine
Description
Summary:The beneficial impact of walnuts on human health has been attributed to their unique chemical composition. In order to characterize the dietary walnut fingerprinting, spot urine samples from two sets of 195 (training) and 186 (validation) individuals were analyzed by an HPLC-q-ToF-MS untargeted metabolomics approach, selecting the most discriminating metabolites by multivariate data analysis (VIP ≥ 1.5). Stepwise logistic regression analysis was used to design a multimetabolite prediction biomarker model. The global performance of the model and each included metabolite in it was evaluated by receiver operating characteristic curves, using the area under the curve (AUC) values. Dietary exposure to walnuts was characterized by 18 metabolites, including markers of fatty acid metabolism, ellagitannin-derived microbial compounds, and intermediate metabolites of the tryptophan/serotonin pathway. The predictive model of walnut exposure included at least one compound of each class. The AUC (95% CI) for the combined biomarker model was 93.4% (90.1-96.8%) in the training set and 90.2% (85.9-94.6%) in the validation set. The AUCs for individual metabolites were ≤85%. As far as we know, this is the first study proposing a combination of biomarkers of walnut exposure in a population under free-living conditions, as considered in epidemiological studies examining associations between diet and health outcomes.