Bacteroides fragilis enterotoxin upregulates heme oxygenase-1 in dendritic cells via reactive oxygen species-, mitogen-activated protein kinase-, and Nrf2-dependent pathway

Figure 6 Effects of Nrf2 suppression on heme oxygenase-1 expression in dendritic cells stimulated with Bacteroides fragilis s enterotoxin. A: Nrf2 translocation and heme oxygenase-1 (HO-1) expression in B. fragilis enterotoxin (BFT)-stimulated dendritic cells (DCs). DC2.4 cells were transfected with Nrf2-specific shRNA or control RNA. Cells were treated with BFT (100 ng/mL) for 24 h and immunofluorescent microscopy was performed. Each group of cells was stained with the active form-specific anti-Nrf2-Cys Ab (red), anti-HO-1 Ab (green), and DAPI (blue, nucleus). The data are representative of at least five experiments. B: HO-1 expression in cells derived from wild-type and Nrf2^−/− knockout mice. BMDCs derived from wild-type or Nrf2^−/− knockout mice were exposed to BFT (100 ng/mL) for the indicated periods. Expression of HO-1 protein in each panel was measured by ELISA (mean ± SE, n=5). ^aP < 0.05 vs each group of cells derived from wild-type mice. HO-1: Heme oxygenase-1; BFT: Bacteroides fragilis toxin; WT: Wild-type; KO: Knockout.