FIG. 8.

DFO, not 3-methyl adenine, prevents the mitochondrial generation of hydroxyl radicals. (A) SH-SY5Y cells cultivated on coverslips were preincubated or not with 3MA or DFO, exposed to 200μM H₂O₂ (perox) for 15 min, and then processed for detection of ROS with the H₂DCF-DA probe. DCF-positive puncta are observed in peroxide-treated cells. DFO, not 3MA, could prevent DCF oxidation by H₂O₂. Quantification and statistical analysis of DCF-positive cells is reported. (B) SH-SY5Y cells cultivated on coverslips were preloaded with the H₂DCF-DA probe, exposed to 200μM H₂O₂ (perox) for 5 min, labeled with Rhodamine 123 (Rho), and immediately observed under the fluorescence microscope. In peroxide-treated cells, DCF-positive and Rhodamine-positive puncta largely (> 85% puncta) colocalize. Images shown in these figure are representative of five independent experiments. Bar = 10 μm.