[Hydrogen dioxide increases the expression of vascular endothelial growth factor in human bronchiolar epithelium cell via a PI3K-dependent pathway].

ABSTRACT

OBJECTIVE: To investigate the effect of hydrogen dioxide (H(2)O(2)) on the expression of vascular endothelial growth factor (VEGF) in human bronchiolar epithelial (HBE) cells. METHODS: MTT assay was used to assess HBE cell viability after exposure to different concentrations of H(2)O(2). VEGF/beta-actin gene fragments were amplified simultaneously by RT-PCR from the total HBE cell RNA, and VEGF protein expression in the cells was detected using ELISA. RESULTS: The exposure to 200 micromol/L H(2)O(2) did not obviously affected the cell viability. Compared with those in the control cell, VEGF165/beta-actin and VEGF189/beta-actin ratios were significantly increased in the cells after treatment with 50, 200, and 600 micromol/L H(2)O(2) (P<0.05). The protein expression of VEGF significantly increased after 50 micromol/L H(2)O(2) treatment (P<0.05), but significantly decreased with pretreatment with the PI3K inhibitor Ly294002 (P>0.05). CONCLUSION: Oxidative stress increases the expression of VEGF via a PI3K-dependent pathway in human bronchiolar epithelial cells, which may play an important role in the onset and maintenance of chronic inflammation in asthma.