Figure 8

Roflumilast N-oxide regulation of TLR3 expression and molecular pathway implicated in corticosteroid efficacy. BEAS2B cells were pretreated with or without cigarette smoke extract (CSE) 1% for 1 hour followed by the incubation in the presence or absence of different concentrations of roflumilast N-oxide (RNO) or dexamethasone (DEX) for 1 hour. After drug incubation cells were stimulated with the TLR3 agonist poly I:C for 24 hours and total mRNA was extracted to quantify the expression of (A) TLR3, (B) TRIF, (C) HDAC2, (D) MIF, and (E) MKP1 genes by real time PCR. Each graph represents the mean ± SEM of 3–4 independent experiments. One-way repeated measures analysis of variance (ANOVA) were performed. Post hoc Bonferroni test: *P < 0.05 compared with control; #P < 0.05 compared with stimulus; _┸ P < 0.05 compared with monotherapy.