FIGURE 8.

gadd7 regulates general ROS amplification. A, WT cells were treated with 1 mm H₂O₂ or 100 μm xanthine and 150 microunits/ml xanthine oxidase (X:XO) for 4 h. gadd7 expression was determined by qPCR and is reported normalized to β-actin RNA expression. All data are expressed as mean ± S.E. for a minimum of 6 measures per condition. *, p < 0.005 for treated versus untreated cells. B, WT and 2E1 cells were treated with 2.3 mm H₂O₂ or 100 μm xanthine and 15 microunits/ml xanthine oxidase for 30 min or 2 h, respectively. Generation of ROS was measured by CM-H₂DCFDA labeling and flow cytometry. All data are expressed as mean ± S.E. for three independent experiments. *, p < 0.05 for treated 2E1 versus treated WT.