The results showed that administration of magnolol-loaded PLGA-PEG nanoparticles significantly reduced airway hyperresponsiveness, lung tissue eosinophil infiltration, and levels of IL-4, IL-13, TGF-β1, IL-17A, and allergen-specific IgE and IgG1 in OVA-exposed mice compared to their empty nanoparticles-treated mouse counterparts. The gene discussed is IL4; the disease is airway hyperresponsiveness.