Fig. 4

Cellular redox environment changes across treatment groups. SAD SiNPs induced a strong general ROS response (A) which was found to be disproportionately high in mitochondria (B). Higher concentrations of SAD SiNPs were also found to induce greater morphological changes in HK-2 cells. Treatment with SAD SiNPs promoted changes in PRX1 indicative of increased oxidation in the cytosolic compartment (C). PRX3 results (D) indicate that this response was particularly pronounced in the mitochondria. Pristine 200 nm SiNPs induced minor changes in early timepoints which returned to control levels by 24 h. Data is presented as mean and SEM (N = 4). Data was analyzed with one-way ANOVA (P value: <0.0001) and Dunnett’s multiple comparison test for group-to-control comparisons (* indicates a P value: <0.05). Imaging was performed in live cells with the following stains: CellROX (green) for general ROS, MitoSOX (red) for mitochondrial superoxide, Hoechst 33,342 (blue) for nuclei, and CellMask (yellow) for F-actin. Images are representative of 3 independent experiments and band intensity was quantified via ImageJ. SAD HD: SAD High Dose (25 µg/mL)