RESEARCH ARTICLE Open Access Inhibitory effects of Stemo t

Full list of author information is available at the end of the articleBackground Cigarette smoke (CS) comprises more than 4,500 com-pounds, including human carcinogens and many toxins such as nicotine, carbon monoxide [1]. CS, which is one of the risk factors of chronic obstructive pulmonary dis-ease (COPD), increases various respiratory symptoms resulting from functional lung abnormalities such as a reduced forced expiratory volume in 1 sec (FEV1) [2]. CS induces lung inflammation through different types of mechanisms, including reduced fibroblast prolifera-tion and migration, and genetic mutations in the lung [3-6]. Furthermore, various types of inflammatory cells, cytokines and chemokines are widely studied with re-gard to the activation of acute or chronic inflammation in the lungs, which may be important factors for under-standing the mechanisms of lung inflammation and devel-oping new approaches to treat lung diseases includin