Mitochondrial membrane potential and cellular ROS level in HT22 cells exposed to glutamate (4 mM) and treated simultaneously with or without 100 nM selenium.

<p>(<b>A</b>) Micrograph of HT22 cells treated with glutamate shows mitochondrial membrane potential change as measured with TMRM. (<b>B</b>) Quantitative analysis of TMRM–mitochondrial membrane potential shows that glutamate-induced mitochondrial hyperpolarization, which peaked at 12 h after glutamate exposure. (<b>C</b>) Micrograph of mitochondrial membrane potential with JC-1 revealed polarized cells in control whereas glutamate exposure resulted in hyperpolarization and depolarization of cells after 24 h. arrow = polarized, arrowhead = hyperpolarized and *(asterisk) = depolarized cells (<b>D</b>). Bar graph shows that selenium normalized glutamate-induced change in mitochondrial membrane potential at 24 h of exposure. FCCP was used to dissipate mitochondrial membrane potential and served as a positive control. (<b>E</b>) Cellular ROS production measured using DHE. Glutamate significantly increased the production of ROS and selenium successfully prevented the increase in ROS. Data were collected from 5 experiments. Values are means±SD. Two-way ANOVA test followed by post hoc Bonferroni’s test was used for data analysis. *p<0.05, **<i>P</i><0.01 and ***<i>P</i><0.001 <i>vs.</i> control and #p<0.05 vs. non-selenium treated, glutamate exposed cells. Cont, control, Glu, glutamate, Se-, non-selenium treatment, and Se+, with selenium treatment.