Patterns of time since last meal revealed by sparse PCA in an observational LC–MS based metabolomics study
In metabolomics studies, liquid chromatography mass spectrometry (LC–MS) provides comprehensive information on biological samples. However, extraction of few relevant metabolites from this large and complex data is cumbersome. To resolve this issue, we have employed sparse principal component analysis (SPCA) to capture the underlying patterns and select relevant metabolites from LC–MS plasma profiles. The study involves a small pilot cohort with 270 subjects where each subject’s time since last meal (TSLM) has been recorded prior to plasma sampling. Our results have demonstrated that both PCA and SPCA can capture the TSLM patterns. Nevertheless, SPCA provides more easily interpretable loadings in terms of selection of relevant metabolites, which are identified as amino acids and lyso-lipids. This study demonstrates the utility of SPCA as a pattern recognition and variable selection tool in metabolomics. Furthermore, amino acids and lyso-lipids are determined as dominating compounds in response to TSLM.
KeywordsMetabolomics SPCA LC–MS Plasma Time since last meal Observational study
This work is carried out as a part of the research program of the Danish Obesity Research Centre (DanORC, see www.danorc.dk), funded by the Danish Strategic Research Council. This work is also supported by Nordic Centre of Excellence (NCoE) programme (Systems biology in controlled dietary interventions and cohort studies—SYSDIET, P no. 070014).
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