PURPOSE:The Oxidative stress is believed to reduce the expression of vascular endothelial growth factor (VEGF) in airway epithelial cells. VEGF may play a role in pathogenesis of obstructive airway diseases including asthma and COPD. There are many reports that show opposite expression of VEGF in COPD and asthma patients, respectively. we hypothesized that Th1 and Th2 cytokines modulate diffrently the oxidative stress induced VEGF expression in airway epithelial cells.
METHODS:Airway epithelial cells, A549 were exposured to various concentrations of H2O2 and peroxynitrite with or without co-treatment of variable cytokines, including IL-4, IL-13 and IFN-γ. The secretion and expression of VEGF in A549 cells were evaluated by real-time PCR and ELISA. We assesed the effect of Th1 and Th2 cytokine on the VEGF expression of A549 cells that were exposured to oxidant injury.
RESULTS:Both H2O2 and peroxnitrite reduced the expresssion of VEGF mRNA and proteins compared to control. IL-4 or IL-13 treatment alone significantly incresed the expression of VEGF mRNA and proteins and IFN-γ showed no significant effect on the VEGF expresssion. Th2 cytokine IL-4 and IL-13 also enhanced VEGF production of A549 cells compared with A549 cells that were exposured to oxidant alone. but, Th1 cytokine IFN-γ did not oppose the effect of oxidant induced VEGF depression.
CONCLUSION:1) Oxidative stress reduced the VEGF production of airway epithelial cells.2) Th2 cytokines induced VEGF production of airway epithelial cells but not Th2 cytokine.3) Th2 cytokines opposed the effcet of oxidative stress on VEGF expression.
CLINICAL IMPLICATIONS:Th1 and Th2 cytokines may play an important role in modulating VEGF expression of airway epithelial cells. when airway epithelial cells were exposured to oxidative stress, the resultant clinical disorder may be depend on the pattren of VEGF expression which is modulated by cytokine environment.
DISCLOSURE:Yong Hyun Kim, No Financial Disclosure Information; No Product/Research Disclosure Information