The Effect Of Roflumilast And Bambuterol On Airway Responsiveness And Inflammation In OVA-induced Asthma In Guinea Pigs And Rats

ObjectiveTo evaluate the effects of the combination of Roflumilast, a second generation inhibitor of phosphodiesterase (PDE4) and Bambuterol, a long lasting beta-adrenoceptor agonist on asthmatic inflammation and airway hyperresponse, we used ovalbumin-induced asthmatic models in guinea pigs and rats.MethodsRats and guinea pigs were sensitized and stimulated by OVA to induce asthma. Guinea pigs/rats asthma model groups were orally administrated with vehicle, Rofulumilast, Bambuterol or their combination,18 hours after the last OVA-challenge, the lung function and inflammatory response were assessed by determining the amount and classification of inflammatory cells in alveolar lavage, the levels of pro-inflammatory factor in alveolar lavage, the changes of pulmonary resistance compliance induced by methacholine.ResultsThe combination of Roflumilast and Bambuterol more effectively inhibited the infiltration of OVA-induced inflammatory cells into lungs than either Roflumilast or Bambuterol alone. The combination of Roflumilast and Bambuterol also decreased the releases of pro-inflammatory mediators, such as interleukin-5 (IL-5). Furthermore, the combination of Roflumilast and Bambuterol significantly alleviated methacholine-induced increases in pulmonary resistance and decreases in pulmonary compliance in asthmatic model of guinea pigs and rats. However, the combination of Roflumilast and Bambuterol exhibited an additive but not synergistc effect on both inflammatory response and pulmonary function.ConclusionThe combination of Roflumilast and Bambuterol could alleviate the damage caused by asthma more effectively to a certain degree.