Fig. 5

Effect of equivalent concentrations of budesonide (BUD) and fluticasone propionate (FP) on GSK-3β phosphorylation and epithelial barrier dysfunction upon pharmacological inhibition of GSK-3β. a 16HBE cells were seeded in duplicates, grown to confluence, serum-deprived overnight, pre-treated with or without 16 nM BUD and 10 nM FP for 60 min and exposed to vehicle (control) or EGF for 60 min. Phosphorylated GSK-3β (p-GSK-3β) or total GSK-3β was detected by western blotting. GAPDH was used as loading control. Densitometry was performed, protein expression was related to the actin levels and normalized values (Mean ± SEM, n = 6) are shown. * = p < 0.05 between the indicated groups. b, c) 16HBE cells were grown to confluence, serum-deprived overnight, pre-treated with or without 16 nM BUD and 10 nM FP for 2 hours and exposed to vehicle (control), GSK-3β inhibitor CT99021 (b) or the combination of 7.5 % CSE and CT99021 c. Electrical resistance was measured at 400 Hz using ECIS. Resistance levels were normalized to the levels prior to the addition of CSE and/or CT99021. Mean ± SEM levels (n = 3−4) are shown. In the upper panels (b and c), p < 0.01 for CT99021 and CT99201 + CSE versus control, as analyzed by repeated measures ANOVA. The area-under-the-curve (AUC) was calculated and mean ± SEM levels (n = 3−4) are shown. * = p < 0.05 between the indicated groups (repeated measures ANOVA with Bonferroni’s post-hoc test)