Tanshinone IIA sulfonate protects against cigarette smoke-induced COPD and down-regulation of CFTR in mice

Chronic obstructive pulmonary disease (COPD) is a chronic lung disease characterized by abnormal inflammation, persistent and progressive lung function decline. The anti-inflammatory actions of tanshinone IIA, which is the most important active component from Chinese herbal medicine Danshen, have been well studied. However, it remains unknown whether sodium tanshinone IIA sulfonate (STS) protects against the development of COPD. Here we found that STS inhalation (5 mg/kg, 30 min per session, twice a day) significantly attenuated lung function decline, airspace enlargement, mucus production, bronchial collagen deposition, inflammatory responses and oxidative stress caused by cigarette smoke (CS) and lipopolysaccharide (LPS) exposures in mice. Moreover, treatment with STS (10 μg/ml) reduced CS extract (CSE)-induced IL-6 and IL-8 secretion in human bronchial epithelial (16HBE) cells. The anti-inflammatory actions of STS were associated with inhibition of ERK1/2 and NF-κB activations. Interestingly, STS inhibited CS-induced reduction of cystic fibrosis transmembrane conductance regulator (CFTR) in mouse lungs and in 16HBE cells. Treatment with a specific CFTR inhibitor CFTR-Inh172 augmented CSE-induced ERK1/2 and NF-κB-dependent inflammatory responses, but abolished the inhibitory action of STS on IL-6 and IL-8 secretion in 16HBE cells. These results demonstrate that CS-induced COPD and down-regulation of CFTR are prevented by STS.