Figure 3. Acute and persistent oxidative stress in irradiated parental and NS subcultures of U251 and A172 cells.

Comparison of reactive oxygen (ROS), nitrogen (RNS) species and mitochondrial superoxide (MS) levels measured by fluorescence activated cell sorting of cells loaded with CMH₂DCFDA, DAF, and MitoSOX, respectively, 1 and 7 days after irradiation (2 Gy). All values normalized to unirradiated controls set to unity. Error bars represent SEM derived from 4 replicates. Significance between unirradiated controls (asterisks above each bar) and between parental and NS subcultures (asterisks above brackets) are shown.