1014 Dietary Galacto-Oligosaccharides Reduce Airway Eosinophilia and Enhance the Th2 Suppressive Effect of Budesonide in House Dust Mite-Induced Asthma in Mice

Wednesday, 14 October 2015
Hall D1 Foyer (Floor 3) (Coex Convention Center)

Kim Verheijden, PhD student , Utrecht University, Utrecht, Netherlands

Saskia Braber , Utrecht University, Utrecht, Netherlands

Aletta Kraneveld, Dr. , Utrecht University, Utrecht, Netherlands

Johan Garssen , Utrecht University, Utrecht, Netherlands

Gert Folkerts, Prof. , Utrecht University, Utrecht, Netherlands

Linette Willemsen, Dr. , Utrecht University, Utrecht, Netherlands

Background: In house dust mite (HDM) allergic asthma, symptoms occur due to airway eosinophilia and Th2 cell activation. Budesonide is used to treat airway inflammation and hyper-responsiveness. We showed that dietary non-digestible galacto-oligosaccharides (GOS) suppress symptoms in a murine model for HDM-induced asthma. The aim is to study combined dietary GOS and budesonide treatment on allergic asthma in mice.

Methods: BALB/c mice were intranasally (i.n.) sensitized with PBS in presence or absence of 1µg HDM and challenged i.n. with PBS or 10µg HDM on days 7 till 11 while being fed a diet containing 0, 1 or 2.5 w/w% GOS. On day 7, 9, 11, and 13 budesonide was either or not instilled oropharyngeally. On day 14, airway resistance to metacholine and inflammation were determined. Leukocyte subtypes were analyzed in the broncho-alveolar lavage (BAL) and in lung cell suspensions. Mucosal mast cell protease-1 (mmcp-1) was measured in serum and cytokines in lung homogenates.

Results: HDM-allergy significantly increased airway responsiveness and BAL leukocyte numbers. Budesonide treatment suppressed this, which reached significance in mice fed GOS. Budesonide reduced the number of lymphocytes and eosinophils in the BAL. Feeding GOS in absence of budesonide treatment reduced the number of eosinophils as well. In addition, both GOS as well as budesonide reduced mmcp-1 serum concentrations. Interestingly, only in the GOS fed mice, budesonide treatment reduced IL-33 and IL-13 concentrations and the frequency of Th2 cells in the lung.

Conclusions: Dietary intervention using GOS may be a novel way to improve effectiveness of anti-inflammatory drug therapy in asthma.

This study was performed within the framework of Carbohydrate Competence Center (WP25).