Ojeok-san, a traditional Korean herbal medicine attenuates airway inflammation and pulmonary fibrosis induced by repeated ovalbumin challenge

Ethnopharmacological evidence: Ojeok-san, a traditional Korean herbal medicine, is widely used in China, Japan and Korea for treatment of the common cold, pain and fever. Aim of the study: In this study, we investigated the protective effects of Ojeok-san aqueous extract (OJS) against pulmonary fibrosis using a chronic asthma murine model. Methods: Mice were sensitized by intraperitoneal injection of ovalbumin (OVA), followed 1 weeks later by an airway challenge with OVA delivered three times a week for 4 weeks. OJS (50 mg/kg or 100 mg/kg) was also administered by oral gavage once a day for 4 weeks. Results: OJS significantly reduced interleukin (IL)-4, IL-13, eotaxin, immunoglobulin E and the number of inflammatory cells in bronchoalveolar lavage fluid; in addition, it reduced inflammatory cell infiltration and mucus production in the respiratory tract. We found that OJS also attenuated the OVA-induced increase in vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-beta(1) and Smad3 protein in lung tissue, as determined by Western analysis and immunohistochemistry. These inhibitory effects of OJS were accompanied by a reduction in pulmonary fibrosis, consistent with the histopathology of lung tissue stained with Masson's trichrome. Conclusion: Administration of OJS reduced the airway inflammation and pulmonary fibrosis, as well as the level of T helper type 2 cytokines and VEGF and TGF-beta(1)/Smad3 expressions in lung tissue. These results suggest that OJS might represent a useful new oral therapy for the treatment of chronic asthma. (C) 2013 Elsevier Ireland Ltd. All rights reserved.