Figure 4. TMZ protects RGCs from apoptosis via Nrf2/Ho-1 signaling.

(A,B) Western blot analysis demonstrated that TMZ elevated the nuclear translocation of Nrf2 and total expression of Ho-1 in primary RGCs under OGD/R conditions. (C,D) TMZ suppressed OGD/R-induced apoptosis in primary RGCs. SnPP treatment significantly but incompletely reversed TMZ-mediated cytoprotective effect on RGCs. (E,F) Flow cytometry assay of ROS accumulation (FITC+) in RGCs. SnPP resulted in an increase in the proportion of FITC+ cells and inhibited the TMZ-induced antioxidative effect. (G,H) The decrease in PE/FITC ratio indicated significant disruption of the MMP in the SnPP-treated RGCs, which could not be rescued by TMZ treatment. Scale bar =50 μm. The data represent the means ± S.D. (n=8); **P<0.01.