Sappanone A Attenuates Allergic Airway Inflammation in Ovalbumin-Induced Asthma

Background: Sappanone A (SA) is isolated from the heartwood of Caesalpinia sappan and exerts a wide range of pharmacological activities. In the present study, we investigated the protective effects of SA on allergic asthma in a murine model of ovalbumin (OVA)-induced asthma.

Methods: BALB/c mice were sensitized and challenged. Then, the mice were intraperitoneally injected with SA (12.5, 25 and 50 mg/kg) 1 h before OVA challenge; 24 h after the last challenge, the mice were sacrificed, and data were collected by different experimental methods.

Results: The results showed that SA dose-dependently reduced inflammatory cell counts, levels of cytokines IL-4, IL-5 and IL-13, and OVA-specific IgE in bronchoalveolar lavage fluid. The level of IFN-γ decreased by OVA was upregulated by the treatment with SA. Furthermore, SA was found to attenuate the airway inflammation and mucus hypersecretion induced by the OVA challenge. In addition, SA dose-dependently upregulated the expression of Nrf2 and HO-1. SA inhibited OVA-induced asthma by activating the Nrf2 signaling pathway.

Conclusions: These data suggest that SA may have a potential use as a therapeutic agent for asthma.