Suppressive effects of ginsan on the development of allergic reaction in murine asthmatic model.
BACKGROUND
Asthma is a major health problem worldwide, and the morbidity and mortality caused by asthma are on the rise. Corticosteroid therapies for asthma treatment frequently induce many side effects. Therefore, the development of new medicines that have both high efficacy and fewer side effects has been a scientific challenge. Here we tested the effect of ginsan, a polysaccharide derived from Panax ginseng, against allergic reaction in an ovalbumin (OVA)-induced murine asthmatic model in comparison with dexamethasone, and investigated its underlying mechanism.


METHODS
To induce murine asthma, mice were sensitized and challenged with OVA. Ginsan or dexamethasone was administered by injection 3 times a week. Airway hyperresponsiveness, airway inflammation and lung pathology were assessed in order to evaluate the effect of ginsan against asthma.


RESULTS
Ginsan treatment reduced airway hyperresponsiveness, remodeling and eosinophilia. These effects of ginsan were equivalent to those of dexamethasone. Ginsan treatment decreased the IL-5 level in the supernatant of cultured splenocytes, while IFN-gamma and serum IgE were not altered. To elucidate the mechanism of ginsan, expression of inflammation-related genes were screened. Interestingly, ginsan treatment upregulated cyclooxygenase (COX)-1 and COX-2 mRNA, and expression of their proteins in the lung were also increased. PGE(2) in the bronchoalveolar lavage fluid was also increased by the ginsan treatment. Lastly, ginsan inhibited the allergic reaction aggravated by COX inhibitor (indomethacin).


CONCLUSIONS
Ginsan has anti-asthmatic effects, which seem to be partially mediated by enhancing the synthesis of COX gene products.
Lim
You-Jin
YJ
Department of Microbiology, Chonnam National University Medical School, Brain Korea 21 Project, Center for Biomedical Human Resources at Chonnam National University, Gwangju 501-746, Republic of Korea.
Na
Hee-Sam
HS
Yun
Yeon-Sook
YS
Choi
Inseon S
IS
Oh
Jong-Suk
JS
Rhee
Joon-Haeng
JH
Cho
Bok-Hee
BH
Lee
Hyun-Chul
HC