Selection of candidate radiation biomarkers in the serum of rats exposed to gamma-rays by GC/TOFMS-based metabolomics

In the study, gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) techniques coupled with principal components analysis (PCA) were used to investigate metabolite perturbations in the serum of the rats exposed to 0.75, 3 or 8 Gy gamma rays. Male standard deviation rats were gamma-irradiated at doses of 0.75, 3 and 8 Gy (1.9 Gy min(-1)) or sham-irradiated. Serum samples were collected over the first 24 h under the exposure to irradiation in order to analyse the samples by GC/TOFMS. And multivariate data were analysed by PCA. The composition of metabolites in serum yielded distinct metabolomic phenotypes for 0.75, 3 and 8 Gy at 24 h after irradiation. Nine serum metabolites were significantly altered as a result of radiation exposure. Up-regulated metabolites included inositol, serine, lysine, glycine, threonine and glycerol; down-regulated metabolites included isocitrate, gluconic acid and stearic acid. The nine metabolites were significantly altered after ionising radiation for they may be the potential biomarkers for the diagnosis of radiation injury.