Figure 5. Inhibition of CFTR activity decreases Nrf-2 activity and increases H₂O₂ levels.

Normal and CF matched cell pairs incubated with 20 µM CFTR_inh-172 are co-transfected with either a plasmid coding for Firefly luciferase driven by a Nrf-2 (Panel A) or Nrf-1 (Panel B) promoter, and one coding for Renilla luciferase driven by the CMV promoter. Three days following transfection, normalized luciferase activity is measured. Panel C: H₂O₂ levels in cells incubated with CFTR_inh-172 for 72 hrs and stimulated with TNFα/IL-1β (10 ng/ml each). * connotes significant difference (p<0.05) from respective uninhibited controls. Each data bar represents the average of 8 replicate wells in 3 experiments for A, B, and C.