Vitex rotundifolia L. prevented airway eosinophilic inflammation and airway remodeling in an ovalbumin-induced asthma mouse model.

Vitex rotundifolia L. (VR) as long been used in China and Korea in traditional medicine. This study was conducted to evaluate the ability of Vitex rotundifolia L. to prevent airway inflammation and remodeling in an ovalbumin (OVA)-induced murine asthma model. The total cell number and number of inflammatory cells in the bronchoalveolar lavage (BAL) fluid were counted. The levels of cytokines in the BAL fluid and serum IgE levels were measured using an ELISA. For histological analysis, hematoxylin and eosin staining, periodic acid-Schiff staining and immunohistochemistry were evaluated. The release of total cells into the BAL fluid was significantly inhibited in OVA-induced asthmatic mice treated with VR extract. In addition, eosinophilia and lymphocytosis were reduced significantly in mice that received VR extract. Furthermore, levels of the T(h)2 cytokines IL-4 and IL-5 and pro-inflammatory cytokine TNF-α in the BAL fluid and total IgE in serum were markedly suppressed by VR extract. OVA-specific IgE in the serum and IL-13 in the BAL fluid were decreased, but not significantly. The allergic effects of VR extract were accompanied by a reduction in airway hyperresponsiveness. Additionally, morphologic findings demonstrated that VR extract substantially inhibited OVA-induced eosinophilia, goblet cell hyperplasia and smooth muscle mass production. This finding suggests that VR extract may have pharmacological effects that would be useful for the treatment of asthma via the inhibition of the T(h)2 response and airway remodeling.