Figure 6
Mitochondrial stress triggered by NPs in HUVEC-STs. (A) Schematic overview of perturbations in mitochondrial functions, which may occur after NP treatment. (B) ROS production in cells treated with NPs (100 μg/mL of PLA/EDTMP, PLGA/MDP, and PLA/MMT/TRA or 0.025 μg/mL of Pluronic F127 Ms) for 24, 48, and 72 h. DCF fluorescence intensity in control cells was set to 100%. Each value represents average ± SD of four independent experiments, *p < 0.05, **p < 0.01, and ***p < 0.001 for significant differences compared to control cells, #p < 0.05, ##p < 0.01 for significant changes compared to samples preincubated with NAC and subsequently incubated with nanosubstances. (C,D): Changes in mitochondrial membrane potential of HUVEC-STs seeded into black 96-well titration microplates and incubated with NPs (100 μg/mL of PLA/EDTMP, PLGA/MDP, and PLA/MMT/TRA or 0.025 μg/mL of Pluronic F127 Ms) for 24, 48, and 72 h (C) or FCCP (D). Fluorescence ratio of JC-1 dimers to JC-1 monomers in control was assumed to be 100%. Results are presented as means ± SD of four experiments. *p < 0.05, **p < 0.01 for significant differences between NP-treated and untreated control cells (taken as 100%); (E) Bax, Bcl2, Cyt c, and AIF gene transcript expression (relative to HPRT1 housekeeping gene) in HUVEC-STs exposed to examined nanosubstances: PLA/EDTMP, PLGA/MDP, and PLA/MMT/TRA (100 μg/mL) or Pluronic F127 Ms (0.025 μg/mL). Asterisks refer to level of significant (**p < 0.01, ***p < 0.001; n = 3) difference in expression in cells treated with investigated NPs compared to untreated cells.
