Pinellia ternata, Citrus reticulata, and Their Combinational Prescription Inhibit Eosinophil Infiltration and Airway Hyperresponsiveness by Suppressing CCR3+ and Th2 Cytokines Production in the Ovalbumin-Induced Asthma Model

Background and Objective. This study was aimed to analyse the curative effects of Pinellia ternata, Citrus reticulata, and their combination on airway hyperresponsiveness (AHR) to inhaled methacholine, pulmonary eosinophilic infiltration, Th2 cytokine production, and IgE and histamine production in a murine model of asthma. Methods. For this purpose, BALB/c mice were systemically sensitized to ovalbumin (OVA) followed intratracheally, intraperitoneally, and by aerosol allergen challenges for 12 weeks. We examined the development of pulmonary eosinophilic accumulation, control of Th2 cytokine, immunoglobulin E (IgE), and histamine productions in a murine model of asthma. Results. Our data suggest that the therapeutic mechanism by which Pinellia ternata, Citrus reticulata, and their combinational prescription effectively treats asthma is based on reductions of eosinophil infiltration, eotaxin receptor (CCR3), histamine, OVA-specific IgE productions in serum, and Th2 cytokines (IL-5, IL-13) by marked reductions of IL-5 and IL-13 mRNA expression in lung tissue. Conclusions. These findings provide evidence that Pinellia ternata, Citrus reticulata, and their combination play a regulatory role in allergic inflammation and offer therapeutic approaches as novel CCR3 antagonists for treatment asthma. However, it is not clear whether pharmacological activities of prescription composed of two herbs are potentiated due to synergistic effect or additive effect.