[Hepatotoxicity of perfluorooctanoic acid in human hepatocytes using metabonomics]

Ultra performance liquid chromatography coupled to orthogonal acceleration time-of-flight mass spectrometry was used to study metabolic profiling of L-02 human liver cell exposed to different doses of perfluorooctanoic acid (PFOA) for 72 h. Principle component analysis method was used for group differentiation and biomarker screening. Dose-dependent distribution of the treated samples with different doses could be observed in scores plots obtained under both positive and negative ionization modes. Furthermore, eighteen metabolites were identified as potential biomarkers which were closely related with the toxicity of PFOA. The identified biomarkers included carnitine and acylcarnitines, nucleosides and nucleoside conjugates, amino acids and amino acid conjugates etc. Among them, significant changes of carnitine and its metabolites were observed in the control group and dose groups, which play an important role in fatty acid metabolism. Meanwhile, some genes involved in cholesterol biosynthesis were upregulated dramatically using gene microarray analysis. The disturbance of cholesterol biosynthesis could have adverse impact on fatty acid metabolism, consequently induce the decrease of carnitine and increase of acylcarnitines in treated groups. Additionally, purine metabolism, tricarboxylic acid cycle, glycosphingolipid metabolism and amino acid metabolism may also be involved in the toxic response to PFOA.