Pathogenesis of cigarette smoke-induced chronic obstructive pulmonary disease and therapeutic effects of glucocorticoids and N-acetylcysteine in rats.

Abstract

Cigarette smoke exposure increases IL-4 levels and decreases IFN-gamma levels. This may be the result of smoke-induced changes in lung function. Budesonide can mitigate the changes in IL-4 and IFN-gamma levels induced by smoke exposure. N-acetylcysteine has no effect on IL-4, but increases IFN-gamma levels and brings the IL-4/IFN-gamma ratio back to normal. Cigarette smoke can also promote MMP-12 gene expression and elevate the MMP-12/TIMP-1 ratio. This effect may play a role in smoke-induced emphysema. Budesonide and N-acetylcysteine do not alter the MMP-12/TIMP-1 ratio in this study when given in the late phase of smoke exposure.