Macelignan attenuated allergic lung inflammation and airway hyper-responsiveness in murine experimental asthma

Aims Macelignan isolated from Myristica fragrans Houtt. is widely used for spice and flavoring for foods, and has been reported to have anti-inflammatory activity. The aim of this study was to investigate the effects of macelignan on allergic lung inflammation with a murine model of experimental asthma. Main methods Fungal protease mixed with chicken egg ovalbumin allergen was used as a challenge to induce murine experimental asthma. To determine its effects on allergy and inflammation, macelignan was administered orally during allergen challenge, and the symptoms of allergic asthma and its underlined mechanisms were examined. Key findings Treatment with macelignan attenuated eosinophilic airway inflammation and airway hyper-responsiveness. With the administration of macelignan, interleukin-4 (IL-4) producing cells, but not interferon-γ (IFN-γ) or IL-17 producing cells, were diminished in the lungs. Additionally, activation of the T helper type 2 (Th2) cell-specific master transcription factor, GATA3 was decreased with macelignan treatment. Finally, production of IL-4 but not IFN-γ or IL-17, by CD4⁺ T cells was reduced with stimulation when combined with the administration of macelignan. Significance Our data show that macelignan has anti-inflammatory effects on Th2 cell-mediated allergic lung inflammation and could potentially provide a novel preventative and/or therapy for the treatment of allergic diseases.