Figure 5.

Effects of endocytosis and NADPH oxidase inhibitor on DNA damage by silica particle treatment. Effects of endocytosis inhibitor (A and B) or NADPH oxidase inhibitor (C and D) on DNA strand breaks induced by silica particle treatment in HaCaT cells. (A and B) HaCaT cells were pretreated with 10 mM cytochalasin D (Cyto D) for 30 min (Cyto D + nSP70) or nSP70 alone, prior to incubation with 90 mg/ml nSP70 for 3 h. (C and D) HaCaT cells were pretreated with 40 mM apocynin (Apo) for 30 min (Apo + nSP70) or nSP70 alone, prior to incubation with 90 mg/ml nSP70 for 3 h. As a positive control, HaCaT cells were treated with 0.2 mM H₂O₂ for 3 h. (A and C) Column height shows the tail length. (B and D) Column height shows the tail moment. Data shown are means ± SD of at least 16 cells per sample. Results shown are representative of more than three independent experiments. *P < 0.01.