Fig. 3

FSZ nanoparticles inhibited apoptosis and maintained mitochondrial homeostasis. PC12 cells were co-cultured using 100 μM TBHP and PBS, SSSe, ZIF-8, Fer-1, SSe@ZIF-8, and FSZ nanoparticles. (A) CCK-8 assay was used to determine cell viabilities. (B) TUNEL staining was used to detect apoptosis (red). (C) Tunel-positive cells were quantified. (D) Measurement of mitochondrial membrane potential was performed with JC-1 staining. The JC-1 monomer (Green) accumulates in mitochondria, indicating that the membrane potential decreased. (E) Quantification of mitochondrial membrane potential after staining (Red/Green). (F) PC12 cells were stained with Mito-tracker Red, which is a mitochondrial superoxide indicator, and (G) the fluorescence intensity of MitoSOX was quantified. (H) Ultrastructure of the PC12 cells were co-treated with or without FSZ nanoparticles and 100 μM TBHP. Statistical analysis was performed using one-way ANOVA. Scale bar: 100 μm. *P < 0.05, **P < 0.01, and ***P < 0.001, compared with the PBS group; #P < 0.05, and ##P < 0.01 compared with the SSSe group