RESUMO
<p><b>OBJECTIVE</b>To investigate the inhibitory effects and mechanism of apigenin (APG) on dominant response of Th2 cells in asthma model of mice.</p><p><b>METHODS</b>Thirty-two 6-week-old healthy BALB/c mice, SPF grade, were randomly divided into four groups equally, the normal control group (A), the asthma model group (B), and the two APG groups (C and D) consisted of asthma model mice treated respectively with high-dose (20 mg/kg per day) and low-dose (2 mg/kg per day) APG given by dissolving in 1% dimethyl sulphoxide via intraperitoneal injection. The murine asthma model was established by ovalbumin (OVA) sensitization and provocation. Twenty-four hours after the last airway provocation, acetylcholine (Ach) was administered via caudalis vein for measuring airway resistance by pulmonary function detector; levels of IL- 4 and IL-13 in bronchoalveolar lavage fluid (BALF) and total IgE in serum were determined by enzyme-linked immunosorbent assay (ELISA); total and differential cell counts in BALF were measured by light microscopy; the airway inflammatory infiltration was detected by haematoxylin and eosin (HE) staining; and the signal transducer and activator of transcription 3 (GATA-3) in the lung tissue was determined by Western blot analysis.</p><p><b>RESULTS</b>As compared with Group A, the airway hyper-reactivity, airway inflammation, cell count and eosinophil percentage in BALF, levels of total serum IgE and BALF IL-4 and IL-13, and GATA-3 protein expression in the lung tissue were significantly increased in Group B (P < 0.05). As compared with Group B, all the above-mentioned indices in Group C and D were lower, showing respective significant difference (P < 0.05), and significant difference was also shown between the two APG treated groups (P < 0.05).</p><p><b>CONCLUSION</b>APG could reduce the airway inflammation and hyper-reactivity by down-regulating the expressions of pulmonary GATA-3 and Th, cytokines, which is a potential drug for asthma therapy.</p>