Oral Delivery of Bavachinin-Loaded PEG-PLGA Nanoparticles for Asthma Treatment in a Murine Model.

T helper type 2 (Th2) cytokines, such as interleukin (IL)-4, IL-5, and IL-13, are the central therapeutic targets in the development of drugs against asthma. Recently, it was found that bavachinin, an essential small molecule in Psoralea corylifolia, has very efficient therapeutic function in asthma treatment in a murine model via the selective inhibition of Th2 cytokine production. However, the clinical potential of bavachinin is limited by its extremely low water solubility (<30 ng/mL). Here, we fabricated a nanoparticle delivery system for the oral administration of bavachinin to treat asthma, with the aim of solving its administration problem. In this study, bavachinin-loaded PEG5000-PLGA NPs were prepared through an emulsion-solvent evaporation technique, and their physical properties were carefully characterized. These NPs showed strong enrichment capability towards inflamed lung tissues. Through oral administration, these NPs showed very good anti-asthma therapeutic effects in murine asthma model, as demonstrated by a histological analysis of lung sections, enzyme-linked immunosorbent assay (ELISA) analysis of Th2 cytokine expressions, and fluorescence-activated cell sorting (FACS) analysis of Th1/Th2 cell differentiation. This system has the potential to be used for the oral delivery of bavachinin to treat asthma and may have potential for the oral delivery of other drugs that have limited pharmacokinetic efficacy.