Fig. 7.

Nrf2 siRNA but not ATF4 siRNA reduces the anti-inflammatory effects of sterubin. BV-2 cells were transfected with control siRNA, ATF4 siRNA or Nrf2 siRNA 24 h before seeding. (A) Nuclear extracts from untreated and sterubin-treated (4 h, 10 µM) cells were analyzed by Western blotting for Nrf2 or ATF4 with actin as a loading control. (B–D) Transfected BV2 cells were treated overnight with 50 ng/ml LPS and the indicated concentrations of sterubin. Cell culture supernatants were cleared and assayed for NO by the Griess assay or pro-inflammatory cytokines using specific ELISAs. Results are presented as the percent (%) of the value obtained with LPS alone which was set at 100%. NO (B); IL6 (C) or IL-1β (D). Results in (B)–(D) are the average of three independent experiments. * p < 0.05 relative to control siRNA transfection; ** p < 0.01 relative to control siRNA transfection; *** p < 0.001 relative to control siRNA transfection.