[Effects of Fritillariae Cirrhosae Bulbus on MMP-2,MMP-9 and TIMP-1 in murine asthma model].

To investigate the effects of Fritillariae Cirrhosae Bulbus on airway remodeling and matrix metalloproteinase-2(MMP-2), matrix metalloproteinase-9(MMP-9), tissue inhibitor-1 of metalloproteinase(TIMP-1) of a murine asthma model, and explore its mechanism in treatment of asthma. BALB/C murines were randomly divided into the normal group, model group, high dose group, low dose group, and positive control group. Except for the normal group, all the other groups received ovalbumin(OVA) to establish murine asthma model. After successful modeling, the murines in high dose group and low dose group were orally administered with Fritillariae Cirrhosae Bulbus powder at the dose of 18.0 mg•kg⁻¹ and 9.0 mg•kg⁻¹, respectively; the murines in positive control group were injected intraperitoneally with dexamethasone at the dose of 0.5 mg•kg⁻¹; while the murines in normal group and the model group were orally administered with the same volume of normal saline. All the drugs were given to murines per day for 28 d. The variations of airway responsiveness, variations of the total cell count and leukocyte differential count in bronchoalveolar lavage fluid(BALF), and the variations of thicknesses of bronchial wall and airway smooth muscle of each group were observed. The levels of MMP-2, MMP-9 and TIMP-1 were measured by ELISA; and the expression levels of MMP-2, MMP-9 and TIMP-1 mRNA were detected by RT-PCR. The results showed that as compared with the normal group, the airway responsiveness, the count of total cells, neutrophils, macrophage, lymphocytes, eosinophils in BALF, and the thicknesses of bronchial wall and airway smooth muscle were increased significantly in the model group(P<0.01); as compared with the model group, the above indicators were decreased significantly in the high dose group, low dose group and positive control group (P<0.05 or P<0.01). As compared with the normal group, the levels and expressions of MMP-2, MMP-9 and TIMP-1 mRNA were increased significantly in the model group(P<0.01); while as compared with the model group, these levels were decreased significantly in the high dose group, low dose group and positive control group(P<0.01). In conclusion, Fritillariae Cirrhosae Bulbus can improve airway remodeling in a murine asthma model, and its mechanisms may be related to down-regulating MMP-2, MMP-9 and TIMP-1 levels.