Our model of experimental COPD showed that lung fibrosis was closely associated with reduced levels of many Nrf2-inducible antioxidant proteins (i.e., SOD, catalase, and GSH) in the lungs of CSE-treated animals, and whether this was due to the action of growth factors remains an interesting hypothesis to be examined in future studies. The gene discussed is CAT; the disease is pulmonary fibrosis.