The effect of administration NF-κB decoy ODNs on the structure of pulmonary parenchyma and the expression of pro-MMP-9 or TIMP-1 in the long-term smoke-induced mice. (A)NF-κB decoy ODNs significantly induced high levels of pro-MMP-9 but not TIMP-1 in the BALF of mice. Data were expressed as mean ± STD (n = 8). Symbols delineate statistical significance compared to NS mice (*, P < 0.05) and Scr mice (#, P < 0.05). (B) Lung parenchyma from NS, Decoy or Scramble-treated smoke-exposed mice at 92 days. Mice were exposed to smoke for 92 days, then they were killed 1 day after the last exposure and their lungs processed for light microscopy with haematoxylin-eosin staining. The lesion was characterized by disseminated foci of airspace destruction interspersed by apparently normal parenchyma. Original magnification 100×, Bar = 200 μm. NS: normal saline-treated smoke-induced mice; Decoy: decoy NF-κB ODNs-treated smoke-induced mice; Scr: scrambled ODNs-treated smoke-induced mice. n = 8.