Fig. 5.

Effects of RTA 408 treatment on levels of GSH, GSSG, and protein-GSH mixed disulfide (PSSP) levels. Cells were pretreated with 100 nM RTA 408 for 24 h followed by 200 μM H₂O₂ challenge for 6 h. GSH levels (A), GSSG levels (B) were measured as described in Materials and Methods. (C) Comparison of protein glutathionylation (PSSG) levels in RTA 408 pretreated cells. The cells were treated with 1 mM H₂O₂ for 30 min and total proteins were separated on a 12% SDS-gel under non-reducing condition (no β-mercaptoethanol) for western blot analysis using an anti-PSSG antibody. (D) The relative pixel density of all the PSSG bands compared to β-actin. Data are mean±SD of three independent experiments, **P<0.01, and ***P<0.001, comparing with H₂O₂ only group, (n=3).