Effect of okam on inflammation and remodeling of airway of mice with ovalbumin induced asthma

Abstract

To investigate the effect of okam on inflammation and remodeling of airway in mice with ovalbumin (OVA) induced asthma. Thirty-two mice of Kunming strain were divided into four groups randomly: model group, glucocorticoid inhalation group, okam group and control group, with 8 mice in each group. The asthmatic mice model was reproduced by combined injection and aerosol inhalation of OVA. The mice in model group received normal saline (0.3 ml) gavage daily. The mice in glucocorticoid inhalation group received budesonide (0.4 ml, 200 mug) and normal saline (3.6 ml) inhalation. The mice in okam group were gavaged with okam daily (50 mg/kg). The controls were given normal saline instead of OVA sensitization. All mice were sacrificed 42 days later, followed by lavage of tracheo-bronchial tree of the right lung, and the right lung was saved for pathological examination. The total cell number and differentiation in bronchoalveolar lavage fluid (BALF) were counted under microscope. The expression of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) in BALF were assessed by enzyme linked immunosorbent assay (ELISA). The histological changes in the bronchi and alveoli were evaluated after hematoxylin and eosin (HE) staining. The expression of matrix metalloproteinase-9 (MMP-9) as well as the tissue inhibitor of metalloproteinase-1 (TIMP-1) were determined by immunohistochemistry. Compared with the model group, the total cell count and IL-4 level in BALF, and the score of pathological changes in the broncho-alveolar tissue in okam group or glucocorticoid inhalation group were lower significantly, and the IFN-gamma level elevated markedly (all P<0.01). The MMP-9, TIMP-1 expression in glucocorticoid inhalation group and the TIMP-1 expression in okam group were decreased greatly (P<0.05 or P<0.01). All of above indexes showed marked differences between control group and okam group (P<0.05 or P<0.01). There were significant changes in the total cell count, IFN-gamma, pathological changes, MMP-9 and TIMP-1 between the glucocorticoid inhalation group and the okam group (P<0.05 or P<0.01). Okam may alleviate inflammation of the bronchial and degrade the development of airway remodeling to some degree.