Oridonin activates multiple cellular signaling pathways. (A) NB4 cells were treated with 5 μM H2O2 for 4 h. RARα protein levels were examined by redox diagonal electrophoresis, followed by western blot analysis for RARα. (B) NB4 cells were treated with 10 μM oridonin for the indicated times, and cell lysates were western blotted for the proteins indicated. (C) NB4 cells were treated with 10 μM oridonin for the indicated times. The intracellular localization of p65 was analyzed by indirect immunofluorescence using anti-p65 antibodies (green). Nuclear DAPI staining (blue) is also shown. Scale bars represent 20 μm. All experiments were repeated three times and gave consistent results.