OBJECTIVETo investigate the effect of Tripterygium polyglycosid on establishing airway eosinophil infiltration and related airway hyperresponsiveness of asthmatic mice.

METHODSA mature murine asthmatic model was made with ovabulmin sensitized and challenged C57BL/6 mice. Forty mice were divided into four groups with 10 mice in each group: mice sensitized and challenged with saline (WS group), mice sensitized and challenged with ovalbumin (WO group), mice sensitized and challenged with ovalbumin and treated with Tripterygium polyglycosid (TP group) and Dexamethasone (DXM group). The mice were intraperitoneally injected with 20 μg chicken ovabulmin emulsified in injected alum on days 0 and 14, then were challenged with an aerosol generated from 1% ovabulmin on days 24, 25 and 26. Tripterygium polyglycosid was injected intraperitoneally at 50 mg/kg on days 25, 26 and 27 after ovabulmin challenge. Dexamethasone was administrated to mice at 2 mg/kg on day 21, 23 before ovabulmin challenge. The airway hyperresponsiveness, mucus production, eosinophils in parabronchial area and bronchoalveolar lavage fluid and the level of interleukin-5, granulo-macrophage clone stimulating factor in bronchoalveolar lavage fluid were measured as indexes of inflammation.

RESULTSTripterygium polyglycosid treatment after ovabulmin challenge completely inhibited eosinophil infiltration in bronchoalveolar lavage fluid [(0.63 ± 0.34)× 10(4) vs. (75.0 ± 14.8)× 10(4), P<0.05] and the peribrochial area (12.60 ± 3.48 mm(2) vs. 379.0 ± 119.3 mm(2), P<0.05), mucus overproduction in airway (2.8 ± 1.7 vs. 7.1±5.6, P<0.05), and increased interleukin-5 levels in bronchoalveolar lavage fluid (28.8 ± 2.8 pg/mL vs. 7.5 ± 3.5 pg/mL, P<0.05). Meanwhile, Tripterygium polyglycosid treatment after ovabulmin challenge also partially inhibited airway hyperresponsiveness. The level of granulo-macrophage clone stimulating factor in bronchoalveolar lavage fluid didn't change with drugs intervention.

CONCLUSIONSThe administration of Tripterygium polyglycosid could inhibit the established airway inflammation and reduce the airway hyperresponsiveness of allergic asthmatic mice. It provides a possible alternative therapeutic for asthma.