Effects of theophylline/chitosan/β-cyclodextrin microspheres for oral drug delivery on an asthmatic rat model

Objective:This study aimed to investigate the effects of TH/CTS/β-CD microspheres by oral administration on ovalbumin allergic asthma of a rat model.Methods:Spray drying method was applied for preparing the TH/CTS/β-CD microspheres,which were used in treatment of asthmatic rats.At a predetermined time,the levels of eosinophil(Eos),protein,lactate dehydrogenase(LDH),aspartate transaminase(AST),glutamic pyruvic transaminase(GPT),and creatinine(Cr)were ascertained by automatic hematology and biochemical analyzers.Lung tissue histology was performed by hematoxylin-eosin staining.Results:No significant differences were found about the contents of Eos in the blood,and the contents of Eos,protein and LDH in the bronchoalveolar lavage fluid between the microsphere-treated and dexamethasone-treated groups,but the levels were lower in both treated groups than in the model group.In the microsphere-treated group,the levels of Cr,AST,and GPT in the serum of rats showed no significant differences compared with the normal group.Based on lung histopathological findings,the microspheres attenuated inflammatory cell infiltration and mucus hypersecretion compared with the model group.Conclusion:This study demonstrated that TH/CTS/β-CD microspheres exerted an anti-inflammatory effect and could serve as a novel promising drug delivery system for asthma treatment.