Fig. 5.

TS-induced nuclear translocation of NF-κB and phosphorylation of IκB are mediated through ERK 1/2 signaling pathways. Overnight serum-starved A549 cells in a T25 flask were either directly exposed to 5 ml of freshly generated smoke for different time points as indicated (A) or pretreated with 10 μM U0126 and 20 μM PD98059 for 2 h followed by exposure to 5 ml of freshly generated smoke for 10 min (B). The membranes were probed with antibodies specific for phosphorylated IκB (pIκB), p65, p50, and GAPDH and developed with a chemiluminescence imaging system as described in MATERIALS AND METHODS. GAPDH intensity was used as internal control to normalize the sample loading. These results are representative of 3 independent experiments.