Effects of tumor necrosis factor-α converting enzyme on mucous hypersecretion in inflammatory airway

Abstract

To investigate the effect of tumor necrosis factor-α converting enzyme (TACE) on mucous hypersecretion in inflammatory airway. Mucous hypersecretion model of human lung adenocarcinoma cells A549 was induced by human neutrophil elastase (HNE), and TNF-α converting enzyme inhibitor-1 (TAPI-1), an inhibitor of TACE, was chosen for the inference study. The expression of MUC5AC and TACE was examined. Th e cells were divided into 5 groups: a negative control group, HNE1 (15 nmol/L) group, HNE2 (25 nmol/L) group, HNE3 (50 nmol/L) group and TAPI-1 group. RT-PCR was used to examine MUC5AC and TACE mRNA expression. The protein expression of TACE and MUC5AC was examined by Western blot and ELISA, respectively. HNE induced the TACE and MUC5AC mRNA and protein expression in a dose-dependent manner. Compared with the control group, the increases were all significantly increased in the three dosages of HNE group (P< 0.01). The HNE-induced TACE and MUC5AC mRNA and protein expression were dramatically attenuated in the presence of TAPI-1, an inhibitor of TACE (P< 0.01). TACE participated cell signalling pathway of airway mucous hypersecretion, and could down regulation the level of inflammation airway mucous hypersecretion.