FIGURE 6.

Effects of VDAC1 knockdown on the PQ-dependent H₂O₂ production and the cytotoxicity in HeLa cells. A, lysates from knockdown cells were subjected to Western blot analysis with anti-VDAC1 mAb. Control, cells transfected with the control siRNA; VDAC−, cells transfected with VDAC1 siRNA. The arrowheads indicate VDAC1 protein. B, NADH-PQ-dependent H₂O₂ production on mitochondria isolated from VDAC1-knockdown HeLa cells was estimated by DCF assay. Light bars, mitochondria incubated with 2 mm NADH only; dark bars, mitochondria were incubated with 10 mm PQ and 2 mm NADH. Error bars represent S.D. (n = 3). C, the survival rate of VDAC1-knockdown HeLa cells (VDA1-siRNA) after 24 h of exposure to 222 μm PQ was higher than that of control cells (p < 0.001). Error bars represent S.E. of triplicate experiments.