Abstract
Asthma is one of the most common chronic airway diseases and is characterized by symptoms, such as, wheezing and coughing. Its prevalence in Korea is gradually increasing among children and adults, especially among those older than 60 years. In this study, we investigated the effects of ginsenoside Rg1 (Rg1), one of the major constituents of Panax ginseng Meyer on ovalbumin (OVA) plus Aspergillus protease (A. protease) allergen-induced asthmatic mice. Mice were orally administered Rg1 for 10 days from 8 days after OVA + A. protease sensitization and intranasally administered booster doses of OVA + A. protease for 4 days from 14 days after sensitization. The effects of Rg1 administration on airway hyperresponsiveness (AHR), immune cell distributions in bronchoalveolar lavage fluid (BALF), and serum level of immunoglobulin E (IgE) were investigated at 18 days after sensitization. Histopathological changes in hematoxylin and eosin (H&E)-stained lung sections were also examined. Treatment of OVA + A. protease-sensitized/challenged asthmatic mice with Rg1 significantly decreased total eosinophil counts in BALF as compared with those of phosphate-buffered saline (PBS)-treated sensitized/challenged controls, and significantly decreased methacholine-induced AHR. Furthermore, IgE serum levels were significantly lower in Rg1 administered OVA + A. protease-sensitized asthmatic mice than in PBS-treated sensitized/challenged controls. The study shows Rg1 protects against A. protease allergen-induced asthma in mice.