Effects of SO(2) derivatives on expressions of MUC5AC and IL-13 in human bronchial epithelial cells.

摘要

Sulfur dioxide (SO(2)) is a common air pollutant, and inhaled SO(2) in airway epithelium easily forms its soluble derivatives in vivo (bisulfite and sulfite), which are toxic to the respiratory system and related to the exacerbation of asthma. To investigate the effects of SO(2 )derivatives on the expressions of asthma related genes (MUC5AC and IL-13), the mRNA and protein levels of the two genes in cultured human bronchial epithelial (BEP2D) cells were analyzed using real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) assay, immunocytochemistry method and enzyme-linked immunosorbent assay (ELISA), respectively. The results showed that the mRNA expressions of MUC5AC and IL-13 were significantly increased at different concentrations of SO(2) derivatives (0.0001, 0.001, 0.01, 0.1 and 1.0 mM), and the maximum appeared at 0.01 mM for MUC5AC (3.9-fold) or at 0.001 mM for IL-13 (4.7-fold). Meanwhile, SO(2) derivatives significantly increased the mRNA levels at 0, 0.5, 1, 4 and 24 h post-exposure with the maximum at 4 h post-exposure (25-fold for MUC5AC and 41-fold for IL-13). Furthermore, the protein levels of MUC5AC and IL-13 in BEP2D cells were significantly increased at different concentrations and different time courses exposed to SO(2) derivatives, along with the maximum at 4 h post-exposure. These results lead to a conclusion that SO(2) derivatives can increase the expressions of MUC5AC and IL-13 genes on the transcription and translation levels, and it suggests that SO(2) derivatives can induce mucus over-production and inflammation responses in human bronchial epithelial cells and may have relations with asthma diseases. This might be one of the possible mechanisms that SO(2) aggravates asthma disease.