Paradoxical Relationship between Mn Superoxide Dismutase Deficiency and Radiation-Induced Cognitive Defects
Figure 5
Redox state and mitochondrial mass.
Levels of the advanced lipid peroxidation end product, 4-hydroxynonenal (4-HNE) adducts, (A) and protein nitration product 3-nitrotyrosine (3-NT) (B) were determined by ELISA to monitor the extent of oxidative stress in the hippocampus at 3 months and 5 months of age after a single dose of cranial irradiation (see timeline in Figure 3A). C, a representative western blot image from samples collected following behavioral studies showing APEX, VDAC, and MnSOD. D, relative protein levels of VDAC in the Sod2−/+ cohorts. In order to compare changes in 4-HNE, 3-NT, and VDAC levels in sham and irradiated Sod2−/+ from two different experimental stages – at 3 months of age before behavioral studies and at 5 months of age after behavioral studies – levels in Sod2−/+ mice were calculated as a percentage of their corresponding Sod2+/+ controls. Two-way ANOVA with Bonferroni post test was carried out. P values indicate Bonferroni post test results. There was no treatment×time interaction. Data are presented as mean ± SEM. Sample size: n = 5 each at 3 months of age, and 4 each at 5 months of age for sham and irradiated Sod2−/+.