Cell metabolomics reveals the neurotoxicity mechanism of cadmium in PC12 cells

The heavy metals such as cadmium (Cd) can induce neurotoxicity. Extensive studies about the effects of Cd on human health have been reported, however, a systematic investigation on the molecular mechanisms of the effects of Cd on central nervous system is still needed. In this paper, the neuronal PC-12 cells were treated with a series of concentrations of CdCl2 for 48 h. Then the cytotoxicity was evaluated by MTT (3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyltetrazolium bromide) assay. The IC15 value (15% inhibiting concentration) was selected for further mechanism studies. After PC-12 cells incubated with CdCl2 at a dose of IC15 for 48 h, the intracellular and extracellular metabolites were profiled using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS)-based cell metabolomics approach. As found, the effects of the heavy metal Cd produced on the PC-12 cell viability were dose-dependent. The metabolic changes were involved in the glycolysis and gluconeogenesis, biopterin metabolism, tryptophan metabolism, tyrosine metabolism, glycerophospholipid metabolism, and fatty acids beta-oxidation. These could cause the perturbation of cell membrane, redox balance, energy supply, cellular detoxification, further affecting the cellular proliferation and apoptosis and other cellular activities.