Changes in mucin production in human airway epithelial cells after exposure to e-cigarette vapor with or without nicotine.

Background The emergence of Electronic cigarettes (E-cigarettes) is creating new perceptions of the tobacco market. Unlike traditional Tabacco, the greatest advantage of E-cigarettes is, above all, that it has a less-smell, convenience, and low cost. And most of the people who smoke E-cigarettes have been believed it is not harmful than traditional smoking. The information about the effect of the human health of E-cigarettes is limited and controversial. Methods we studied the effect of E-cigarettes vapor on mucin (MUC5AC and MUC5B) and the change of MUC5AC and MUC5B with or without nicotine in E-cigarettes liquid in respiratory epithelial cells. The effect and signaling pathway of E-cigarettes vapor on mucin with or without nicotine were investigated using reverse transcriptase-polymerase chain reaction (RT-PCR), real-time PCR, enzyme immunoassay, and immunoblot analysis with several specific inhibitors and small interfering RNA (siRNA). Results The effect of E-cigarettes vapor with or without nicotine stimulated MUC5AC expression in respiratory epithelial cells, but MUC5B was not. In addition, we showed that E-cigarettes vapor with and without nicotine induce MUC5AC expression via activation of MAPK (ERK 1/2 and p38) and NF-κB signaling pathways in human airway epithelial cells. Conclusion E-cigarettes vapor with and with nicotine is significantly increased MUC5AC expression in human airway epithelial cells.