This antiasthmatic effect of catalpol in ovalbumin-induced asthma in mice was confirmed by Zou and colleagues who showed that in addition to preventing symptoms, catalpol treatment significantly reduced the total number of inflammatory cells and eosinophils in broncheoalveolar fluid; this was accompanied by a marked reduction in immunoglobin E (IgE) and inflammatory cytokines (IL-1 and IL-4) and a marked increase in interferon-γ (IN-γ). This evidence concerns the gene IL4 and asthma.