Figure 6.

SnPP, a HO-1 inhibitor, attenuates the effects of carnosol and curcumin on MAP Kinase activation, DC maturation and pro-inflammatory cytokine production. DC from healthy donors (n = 3) were incubated with carnosol (10 µM) or curcumin (10 µM), in the presence or absence of SnPP (50 µM), for 6 hours prior to stimulation with LPS for 30 minutes. (A) The activation of the MAPKs MEK and p38 was measured by western blot. Data shown is representative of 3 healthy donors. Full length blots are presented in Supplemental Fig. 7. DC from healthy donors (n = 4) were incubated with carnosol (10 µM), curcumin (10 µM) or a vehicle control, in the presence or absence of SnPP (50 µM) for 6 hours prior to stimulation with LPS for 24 hours. (B) The expression of maturation markers CD83 and CD86 was measured by flow cytometry. Histograms depict expression of CD83 and CD86 in carnosol and curcumin treated DC, with or without SnPP, compared to control DC from one representative experiment. Pooled data (n = 4) shown are mean (±SEM) of the measured MFIs, expressed as percentages of the vehicle control. (C) The concentration of TNFα in cell culture supernatants was measured by ELISA. Results shown are mean (±SD) of two replicates from one healthy donor, and is representative of four independent experiments. Statistical significance was determined by one-way ANOVA, with Sidak’s multiple comparisons post hoc test to compare the means of preselected pairs of groups (**p < 0.01, *p < 0.05).