Inflammation and ER Stress Downregulate BDH2 Expression and Dysregulate Intracellular Iron in Macrophages

Figure 4

ER stress and inflammation induce iron retention in macrophages. THP-1 cells ( cells/mL) were treated with tunicamycin (10 μg/mL) or DMSO overnight prior to LPS exposure (40 ng/mL) for 6 hr and iron retention in macrophages was determined using the calcein-AM fluorescent probe method [40]. DMSO treated cells were incubated simultaneously and used as controls. Calcein-AM fluorescence was measured by excitation at 488 nm and emission at 528 nm wavelength (see Section 2). Calcein-AM fluorescence is quenched upon binding iron and is therefore inversely correlated with intracellular iron accumulation. AU: arbitrary units. Error bars represent the SD from the mean of triplicate reading and data are representative of two independent experiments. values were calculated in reference to vehicle (DMSO) treatment control using one-way ANOVA followed by Bonferroni multiple comparisons post hoc analysis. values annotated ; ; ; were not significant (NS).