Tissue sample stability: thawing effect on multi-organ samples
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Correct handling of samples is essential in metabolomic studies. Improper handling and prolonged storage of samples has unwanted effects on the metabolite levels. The aim of this study was to identify the effects that thawing has on different organ samples. Organ samples from gut, kidney, liver, muscle and pancreas were analyzed for a number of endogenous metabolites in an untargeted metabolomics approach, using gas chromatography time of flight mass spectrometry at the Swedish Metabolomics Centre, Umeå University, Sweden. Multivariate data analysis was performed by means of principal component analysis and orthogonal projection to latent structures discriminant analysis. The results showed that the metabolic changes caused by thawing were almost identical for all organs. As expected, there was a marked increase in overall metabolite levels after thawing, caused by increased protein and cell degradation. Cholesterol was one of the eight metabolites found to be decreased in the thawed samples in all organ groups. The results also indicated that the muscles are less susceptible to oxidation compared to the rest of the organ samples.
KeywordsThawing effect Metabolomics OPLS Multivariate analysis Multi-organ
The authors would like to thank Professor Paul Gissen. The authors would also like to extend their sincere gratitude to Mélanie Fabre for technical support. This research was supported by the Swedish Research Council Grant No. 2011-6044 (to JT), the Biology of Liver and Pancreatic Development and Disease (BOLD) Marie Curie Initial Training Network (MCITN) within EU’s FP7 programme (to TL, JT, KB, FT, SC, CH, TM) and the CNRS and Université Pierre et Marie Curie (to SC, CH), the Institut National de la Santé et de la Recherche Médicale, INSERM (to SC), the Société Francophone du Diabète and Emergence UPMC (to CH). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Conceived and designed the experiments: TL, KLE, SC. Performed the experiments: CH, SC, KB. Analyzed the data: FT, TL, JT, TM, SR, CH, SC, KB. Wrote the paper: FT, KB, SC, CH, JT, TM, TL.
Compliance with ethical standards
Conflict of interest
JT, TM and TL are shareholders of AcureOmics AB. No financing has been received from this company. The authors declare no other competing interests.
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