PM2.5 induces VEGF expression via activation of NF-κB pathway in bronchial epithelial cells / 军事医学

ABSTRACT

Objective To investigate the molecular mechanism of vascular endothelial growth factor ( VEGF) expression in bronchial epithelial cells (Beas-2B)induced by particulate matter 2.5(PM2.5).Methods PM2.5 powder was dis-solved in DMEM medium and diluted into five concentrations , 0,12.5,25,50 and 100μg/ml, respectively.The double an-tibiotics ( streptomycin and penicillin ) and FBS were added into the solution to a 2% final concentration of serum system after being treated by ultrasound for 30 minutes.The cultured Beas-2B cells were then treated with different doses of PM2.5.Subsequently, nuclear factor-kappa B(NF-κB) transactivity and the transcriptional activation of vegf gene promot-er were tested by dual-luciferase reporter gene analysis system while phosphorylation of p 65 , expression levels of IκBαand VEGF were detected by Western blotting .Results PM2.5 induced up-regulation of VEGF expression in Beas-2B cells in a dose-dependent manner , accompanied by NF-κB transactivation at the highest level under 100 μg/ml of PM2.5 treatment. Moreover, PM2.5 induced degradation of the repressor protein IκBαand increase in the phosphorylation level of p 65 sub-unit in Beas-2B cells.Knockdown of NF-κB p65 expression significantly inhibited vegf gene promoter transcriptional activa-tion as well as VEGF protein expression in Beas-2B cells induced by PM2.5.Conclusion PM2.5 induces VEGF expres-sion via activation of NF-κB pathway in bronchial epithelial cells .