Cigarette smoke exposure is the major cause of chronic obstructive pulmonary disease (COPD). Acetylshikonin was the active principle component of Purple Gromwell that show anti-oxidative and anti-inflammatory effect. However, no data are available to elucidate the protective effect of acetylshikonin on COPD. Acetylshikonin could attenuate smoke-induced lung pathological changes, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and monocyte chemoattractant protein 1 (MCP-1) productions, and tissue damages caused by oxidative stress. Furthermore, acetylshikonin was found to enhance the expression of Nrf2 and Nur77-mediated COX-2 in vivo and in vitro. [ABSTRACT FROM AUTHOR]