Effect Of Total Ginkgo Flavone Glycosides On Th₁/Th₂ Balance And The Expression Of Transcription Factor GATA-3 In Bronchial Asthma Mouse

Objective: To investigate the effect of total ginkgo flavone glycosides on airway inflammation, Th1 cytokines,in BALF, total IgE and ovalbumin-specific IgE in serum and the expression of transcription factor in murine asthmatic model; and to analysis the relationship between GATA-3 expression and Th2 cytokines.Exploring the feasibility and the mechanism of treatment bronchial asthma with TFG..Methods: Sixty BALB/c mice were randomly divided into normal group, control group, TFG treated group(little,middle,high) and Dexamethasone treated group.The asthma model was established in BALB/c mice by immunization with OVA and Al(OH)3 . Quantification of IL-4 and IFN-γlevels in bronchoalveolar lavage fluids(BALF) and total IgE,ovalbumin-specific IgE in serum were conducted by ELISA. The changes of pathology by Hematoxylinleosin(HE) were observed and the expression of GATA-3 protein in lungs was detected by immunohistochemical staining.Results:(1) Compared to the model group, the level of IL-4 decreased, IFN–γincreased in BALF, the level of total IgE and ovalbumin-specific IgE in serum in serum also decreased in TFG treated group(P<0.01).(2) In model group, smooth muscle hypertrophing, mucous hyperemia, mucous layer thickening, and inflammatory cell in filtration were appeared . Phlegmasia was appeared in the bronchi, which was filled with lots of mucus. In contrast, the inflammatory reaction in TFG and Dexamethasone treated group was much less.(3) Immunohistochemical staining revealed that expression of GATA-3 was obviously increased in model group, while the percentage of transcription factor GATA-3 positive cells TFG groups were lower significantly (P<0.05,P<0.01).(4) There was a significantly correlation between the content of IL-4 in BALF and transcription factor GATA-3 expression in lungs (r= 0.914, P<0.01); while there was a significantly negative correlation between the content of IFN-γin BALF and the expression of GATA-3 (r =-0.951,P<0.01).Conclution: TFG could inhibit the level of IL-4 in BALF, as well as asthmatic airway inflammation and eosinophils infiltration and the level of total IgE and ovalbumin-specific IgE in serum in mice. Nebulized TFG plays a therapeutic effect in asthmatic mice, whose mechanism maybe explained by TFG could blockade GATA-3 in the lung tissue , restrain the Th2 reaction in order to regulating the disorder Th1/Th2 imbalance .