Nicotine induced expression of high-mobility group box 1 via surfactant proteins A in human airway epithelial cells

Objective To test whether nicotine induces the expression of high-mobility group box 1 (HMGB1) in human bronchial epithelial cells (16HBECs) in vitro via surfactant proteins A (SP-A). Methods 16HBECs were exposed to nicotine (6×10-6 mol/L) for 6 h, 12 h and 24 h, respectively.The secretion of HMGB1 was assessed by enzyme-linked immunosorbent assay (ELISA). Results We showed that cells exposed to nicotine for 24 h exhibited significantly increased HMGB1 secretion, Nicotine treatment had no significant effect on the secretion of HMGB1, although a slight upregulation of HMGB1 secretion was observed at 6 h and 12 h. Knockdown of SP-A with small interfering RNA (siRNA) promoted the secretion of HMGB1. Conclusions These results suggest that nicotine can induce the expression of HMGB1 via SP-A in HBECs. Key words: HBECs; Nicotine; SP-A; HMGB1