Role of HIF-let in phosphodiesterase-4 inhibitor roflumilast mediated effect on MUC5AC expression in human bronchial epithelial

Objective To investigate the role of HIF--1α in phosphodiesterase4 inhibitor roflumi-1αst mediated effect on cigarette smoke extract on induced MUC5AC expression in human bronchial epithelial. Methods Cigarette smoke extract was prepared. And human bronchial epithelial cell I6HBE was treated with roflumi-1αst or cigarette smoke extract or both. Then the MUCSAC and HIF-1α mRNA expression were measured by RT-PCR, the protein expression of MUCSAC and HIF-1α were detected by Western blot. Results As compared with the control group, the expression of MUCSAC and HIF--1α were significantly increased after cells treated with cigarette smoke extract at both mRNA and protein level. While,the cigarette smoke extract induced upregu-1αtion of MUC5AC and HIF-1α were inhibited by roflumi-1αst intervention. Conclusions Phosphodiesterase-4 inhibitor roflumi-1αst can reverse the cigarette smoke extract induced MUCSAC upregu-1αtion by inhibiting HIF -1α, expression. Key words: Roflumi-1αst;  Hypoxia inducible factors--1α;  Cigarette smoke;  Human bronchial epithelial MUC5AC