Figure 4

Inhibitory effects of simvastatin on TLR8 signaling are mediated by inhibition of NF-κB but not AP-1. (A) Inhibition of NF-κB-induced luciferase production in HEK Blue TLR8 cells in response to 16 h incubation with 5 µg/mL R-848 after a 30-min incubation with simvastatin. (B) HEK Blue TLR8 cells were treated with 10 µg/mL simvastatin for 30 min ± 10 µmol/L GGPP before treatment with 5 µg/mL R-848 for 16 h. Cell lysates were examined for phosphorylation of p38 by Western blotting. (C) Primary human monocytes were treated with 10 µg/mL simvastatin ± 10 µmol/L GGPP for 30 min before treatment with 2 µg/mL R-848 for 16 h. Cell lysates were examined for phosphorylation of p38, IKKα/β and TAK-1 by Western blotting. GAPDH was used as a loading control. These blots are representative of three independent experiments. (D) Densitometric analysis of Western blots for phosphorylated IKKα/β. Data are expressed as arbitrary units and are the mean ± SE (n = 3). *p < 0.05 versus R-848-treated samples by Student t test for paired data.