Gelam honey attenuates ovalbumin-induced airway inflammation in a mice model of allergic asthma

Allergic asthma is a chronic inflammatory disorder of the pulmonary airways. Gelam honey has been proven to possess anti-inflammatory property with great potential to treat an inflammatory condition. However, the effect of ingestion of Gelam honey on allergic asthma has never been studied. This study aimed to investigate the efficacy of Gelam honey on the histopathological changes in the lungs of a mice model of allergic asthma. Forty-two Balb/c mice were divided into seven groups: control, I, II, III, IV, V and VI group. All groups except the control were sensitized and challenged with ovalbumin. Mice in groups I, II, III, IV, and V were given honey at a dose of 10% (v/v), 40% (v/v) and 80% (v/v), dexamethasone 3 mg/kg, and phosphate buffered saline (vehicle) respectively, orally once a day for 5 days of the challenged period. Mice were sacrificed 24 h after the last OVA challenged and the lungs were evaluated for histopathological changes by light microscopy. All histopathological parameters such as epithelium thickness, the number of mast cell and mucus expression in Group III significantly improved when compared to Group VI except for subepithelial smooth muscle thickness (p < 0.05). In comparing Group III and IV, all the improvements in histopathological parameters were similar. Also, Gelam honey showed a significant (p < 0.05) reduction in inflammatory cell infiltration and beta-hexosaminidase level in bronchoalveolar lavage fluid. In conclusion, we demonstrated that administration of high concentration of Gelam honey alleviates the histopathological changes of mice model of allergic asthma.