title: Data-handling strategies for metabonomic studies: example of the UHPLC-ESI/ToF urinary signature of tetrahydrocannabinol in humans.
abstract: Metabonomics has become a very valuable tool and many research fields rely on results coming out from this combination of analytical techniques, chemometric strategies, and biological interpretation. Moreover, the matrices are more and more complex and the implications of the results are often of major importance. In this context, the need for pertinent validation strategies comes naturally. The choice of the appropriate chemometric method remains nevertheless a difficult task due to particularities such as: the number of measured variables, the complexity of the matrix and the purposes of the study. Consequently, this paper presents a detailed metabonomic study on human urine with a special emphasis on the importance of assessing the data's quality. It also describes, step by step, the statistical tools currently used and offers a critical view on some of their limits. In this work, 29 urine samples among which 15 samples obtained from tetrahydrocannabinol (delta-9-tetrahydrocannabinol)-consuming athletes, 5 samples provided by volunteers, and 9 samples obtained from athletes were submitted to untargeted analysis by means of ultra high-pressure liquid chromatography-electrospray ionization-time-of-flight mass spectrometry. Next, the quality of the obtained data was assessed and the results were compared to those found in databases. Then, unsupervised (principal component analysis (PCA)) and supervised (ANOVA/PCA, partial least-square-discriminant analysis (PLS-DA), orthogonal PLS-DA) univariate and multivariate statistical methods were applied.
authors.affiliation: Institut des Sciences Analytiques, UMR 5280 CNRS, Equipe TRACES, 5 rue de la Doua, 69100, Villeurbanne, France.
authors.forename: Agneta
authors.initials: A
authors.lastname: Kiss
authors.forename: Claire
authors.initials: C
authors.lastname: Bordes
authors.forename: Corinne
authors.initials: C
authors.lastname: Buisson
authors.forename: Francoise
authors.initials: F
authors.lastname: Lasne
authors.forename: Pierre
authors.initials: P
authors.lastname: Lanteri
authors.forename: Cécile
authors.initials: C
authors.lastname: Cren-Olivé
mesh_terms: D002851:Chromatography, High Pressure Liquid; D057225:Data Mining / Q000706:statistics & numerical data*; D004300:Doping in Sports; D013759:Dronabinol / Q000378:metabolism / Q000652:urine*; D006801:Humans; D055432:Metabolomics; D025341:Principal Component Analysis; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D013759:Dronabinol