Objective: To observe the effects of chronic arsenic exposure on the metabolomics of mouse cortex and serum, and to explore its neurotoxicity mechanism.
Methods: Twelve C57BL/6J three-week-old male rats were randomly divided into two groups according to body weight. The exposure group drank water containing 50 mg/L sodium arsenite for 12 weeks, and the control group drank distilled water. After exposure, the brain arsenic content was determined by hydride generation-atomic fluorescence spectrometry; gas chromatography/mass spectrometry (GC/MS) was used to conduct metabolomics research on the cortex and serum of mice in the arsenic exposure group and control group. Analysis method (PCA) was used to analyze and compare the differences of metabolites between the two groups. Two-sample t test was used to screen the differential metabolites between the two groups, and the online metabolic pathway analysis tool was used to find the relevant metabolic pathways affected by them.
Results: The content of arsenic in the brain of the arsenic exposure group was higher than that of the control group, and the difference was statistically significant (P<0.05); the content of phenylalanine, tyrosine, histidine, lysine and citric acid in the cerebral cortex of the arsenic exposure group Serum levels of serine, glycine, proline, aspartic acid and glutamic acid increased, while the content of α-ketoglutarate decreased. PCA analysis showed that there were differences in the metabolic characteristics of the cortex and serum of the exposed group and the control group, and the difference was statistically significant (P<0.05).
Conclusion: Chronic arsenic exposure can affect the function of the central nervous system by interfering with cortical and serum amino acid metabolism and tricarboxylic acid cycle, leading to neurotransmitter synthesis disorders and interfering with energy metabolism.