Effect Of Subchronic Exposure To Arsenic On Levels Of Essential Trace Elements In Mice Brain

Objective: To investigate the effect of chronic exposure to arsenic (As) on levelsof several essential trace elements Iron (Fe), Copper (Cu), Zinc (Zn), Selenium (Se) andChrome (Cr) in brain of mice, which providing evidences for exploring the mechanismof Arsenic toxicity to central nervous system.Methods:80SPF mice were randomly divided into five groups: the control group(physiological saline group),1ppm As2O3,2ppm As2O3,4ppm As2O3. As2O3wasadministered ad libitum in water for60days. The concentrations of As and Cu, Fe, Se,Zn, and Cr as major essential elements were determined in the cerebrum and cerebellumof mice exposed to arsenic trioxide subchronically by Inductively CoupledPlasma-Mass Spectrometry (ICP-MS). Significant differences between mean valueswere determined by one-way analysis of variance (ANOVA) followed by the Scheffe’stest for multiple comparison, and gender difference was tested by two-way analysis ofvariance (ANONA). All test datas were converted and manipulated by using StatisticalPackage for Social Sciences13.0(SPSS13.0) computer package. P value<0.05wasconsidered statistical significance.Results: The concentration of As was significantly higher in the cerebrum orcerebellum of mice exposed to As than that in control group (p<0.05), and indose-dependent manner. The concentrations of Fe, Se and Cr in the cerebrum orcerebellum were significantly lower in mice exposed to As than those in control group(p<0.05). On the contrary, the concentration of Cu in the cerebrum or cerebellum wassignificantly higher in mice exposed to As (p<0.05). Our results indicate that subchronicexposure to As may decrease the levels of Fe, Se and Cr or increase the level of Cu inthe brain of mice. Moreover, the significant gender difference was found relative to theeffect of As on concentrations of Cu and Se in brain, concentration of Se in cerebrumand concentrations of Cu and Se in cerebellum of mice.Conclusion: The concentration of As was significantly higher in the cerebral and cerebellar tissues of mice exposed As. It indicates that As can accumulate in brain ofmice after subchronic exposure. Subchronic exposure to As may decrease the levels ofFe, Se and Cr or increase the level of Cu in the brain of mice. Moreover, the significantgender difference was shown in effect of As on concentration of Se in cerebrum orconcentrations of Cu and Se in cerebellum of mice. Therefore, more experiments arerequired to demonstrate further whether the observed changes in trace element levelscorrelated closely with the As-induced damages of central nerve system. Meanwhile, itis also necessary to further understand mechanisms that As interacts with essentialelements in brain and induces the gender difference.