Protective Effects of Total Alkaloids from Menispermum dauricum against Airway Inflammation in Asthmatic Mice.

Menispermum dauricumis widely used to treat respiratory inflammation, including laryngopharyngitis, tonsillitis, tracheitis, and bronchitis. Total alkaloids isolated fromM. dauricumhave shown a variety of beneficial bioactivities. However, available data on the effects ofM. dauricumtotal alkaloids against allergic asthma has not been reported. In present study, the protective effect ofM. dauricumtotal alkaloids was evaluated by using an ovalbumin-inducedin vivomodel of asthma. The asthma model was prepared by sensitizing and challenging mice with ovalbumin, andM. dauricumtotal alkaloids (100, 200, and 400 mg/kg) were administrated to asthmatic mice by gavage. Histopathological analysis of pulmonary changes was detected by hematoxylin and eosin, and periodic acid-schiff staining. Inflammatory cell counts were determined in bronchoalveolar lavage fluid. Total immunoglobulin E and ovalbumin-specific immunoglobulin E levels in serum, and T-helper 2 cytokines and chemokine levels in bronchoalveolar lavage fluid were detected by an ELISA. Histological results demonstrated thatM. dauricumtotal alkaloids significantly attenuated pulmonary inflammation in asthmatic mice.M. dauricumtotal alkaloid treatment exhibited marked effects on asthmatic mice in reducing inflammatory cell counts, decreasing interleukin-4, interleukin-5, and interleukin-13 concentrations, and downregulating TNF-alpha and eotaxin levels in bronchoalveolar lavage fluid. In addition,M. dauricumtotal alkaloids could also inhibit the elevated serum levels of total immunoglobulin E and ovalbumin-specific immunoglobulin E. These findings confirmed thatM. dauricumtotal alkaloids could suppress airway inflammation in ovalbumin-induced asthma through regulating the T-helper 2 response and chemokine level.M. dauricumtotal alkaloids may be a potential ethnopharmacological agent for asthmatic patients.