Figure 4. Obacunone activates Nrf2 signaling cascade in RPE cells. ARPE-19 cells (A–F) or the primary murine RPE cells (G–I) were treated with obacunone (“Oba”, 25 μM), cells were further cultured for applied time periods, the co-immunoprecipitation (Co-IP) assay was performed to test Keap1-Nrf2 association (A); Expression of listed proteins (in cytosol lysates and nuclear lysates) and mRNAs were tested by Western blotting (B, C, F, G) and qPCR (E, H) assays, and results were quantified; The relative ARE luciferase activity was tested as well (D,I). Expression of listed proteins was quantified, normalized to the loading control, and expressed as mean ± SD (n=5) (A–C, F, G). Data were presented as mean ± SD (n=5). “Veh” stands for the vehicle control. *p < 0.05 vs. “Veh” treatment. Experiments were repeated three times, with similar results obtained.