Abstract:

Objective To observe the effects of vascular endothelial growth factor (VEGF) receptor inhibitor SU5614 on the expression of VEGF, airway inflammation, and airway responsiveness in mouse models of toluene diisocyanate (TDI) induced asthma. Methods Thirty BALB/C mice were randomly divided into 3 groups (n=10), i.e. the control group, model group, and SU5614 group. Asthmatic models were established by using TDI as the allergen. For the SU5614 group, SU5614 dissolved in dimethylsulfoxide (DMSO) was intraperitoneally injected 1 h before challenge with the dose of 2.5 mg/kg per day for 3 d. For the model group, no medicine was administered before challenge. While for the control group, no medicine was administered and no challenge was conducted. The expression of VEGF, variations of airway responsiveness, and variations of the total cell count and leukocyte differential count in bronchoalveolar lavage fluid of each group were observed. Results Results of the Western blotting and immunohistochemistry analysis showed that the VEGF expression of the model group increased significantly and the VEGF expression of the SU5614 group decreased significantly. The airway responsiveness of the model group was significantly higher than that of the control group and the airway responsiveness of the SU5614 group was significantly lower than that of the model group. The differences were statistically significant (P<0.05). The number of total cells, neutrophils, macrophage, tymphocytes, and eosinophils in bronchoalveolar lavage fluid of the model group were significantly higher than those of the control group and those of the SU5614 group were significantly lower than those of the model group. The differences were statistically significant (P<0.05). Conclusion SU5614 can inhibit the expression of VEGF in bronchoalveolar lavage fluid, decrease the airway hyperresponsiveness, and relieve the airway inflammation.

Key words: asthma, vascular endothelial growth factor, airway inflammation, SU5614