Figure 5
Cellular Cu is required for TPEN toxicity. A) Cellular viability using the MTT assay in cells that were either untreated (CON), incubated with CuSO4 (5 μM, Cu); neocuproine (25 μM, Neo); TPEN (5 μM); pre-incubated with neocuproine (25 μM) for 2 h before TPEN (5 μM) addition (Neo + TPEN); pre-incubated with CuSO4 (5 μM) before TPEN (5 μM, Cu + TPEN5) or TPEN (15 μM, Cu + TPEN15) addition (mean ± SD, n = 3). B) ROS induction using the DCF assay in untreated cells (CON), cells incubated with CuSO4 (5 μM, Cu); neocuproine (25 μM, Neo); H2O2 (250 μM); TPEN (5 μM); pre-incubated with neocuproine (25 μM) for 2 h before TPEN (5 μM) addition (Neo + TPEN); pre-incubated with CuSO4 (5 μM) before TPEN (5 μM, Cu + TPEN5) or TPEN (15 μM, Cu + TPEN15) addition (mean ± SD, n = 3). C) MTT viability assay in untreated cells (CON); cells incubated with bathocuproine ( 5 and 10 μM) or TPEN (5 μM), and in cells pre-incubated with bathocuproine (5 or 10 μM) for 2 hours before the addition of TPEN (5μM) (mean ± SD, n = 3, ** p < 0.01, significant difference with respect to TPEN in A and B).