Alpinia katsumadai seed extract attenuate oxidative stress and asthmatic activity in a mouse model of allergic asthma.

Allergic asthma is a chronic inflammatory disorder of the airways characterized by biphasic airway obstruction. Oxidative stress plays an important role in the development of asthmatic conditions. Thus, identification of oxidative stress markers in bronchoalveolar lavage fluid (BALF) and lung tissue from ovalbumin (OVA)-sensitized mice could provide new insights into both the pathogenesis of the disease and the possible use of anti-oxidants to alleviate disease severity. In this study, we investigated the effect of an ethanolic extract of Alpinia katsumadai seeds (AK) on a murine model of OVA-induced asthma model. The anti-oxidant and anti-asthmatic effects of AK on OVA-induced murine airway reaction were determined through observation of Th2-type cytokine levels, eosinophil recruitment, and lung histopathology. AK was found to significantly inhibit increases in Th2-type cytokines and mRNA expression such as IL-4 and IL-5 in BALF and lung tissue, and effectively suppressed IgE, IgG2a, eosinophilia, and mucus hypersecretion in the asthmatic mouse model. Also, the generation of reactive oxygen species (ROS) in BALF was diminished by AK treatment. These findings indicate that oxidative stress may play a crucial role in the pathogenesis of OVA-induced asthma model and that AK may have applications in the treatment of asthma.