中药川贝母对哮喘模型小鼠MMP-2,MMP-9和TIMP-1的影响

观察中药川贝母对哮喘模型小鼠气道重塑及基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)与基质金属蛋白酶组织抑制剂-1(TIMP-1)的影响,探讨其治疗哮喘的作用机制。BALB/C小鼠,随机分为正常组、模型组、高剂量组、低剂量组、阳性对照组。除正常组外,其他各组用卵蛋白(OVA)建立哮喘小鼠模型。造模成功后高剂量组和低剂量组分别按18.0,9.0 mg·kg-1剂量给予中药川贝母灌胃;阳性对照组于腹腔注射0.5 mg·kg-1剂量地塞米松;正常组和模型组等量生理盐水灌胃,每天1次,连续28 d。观察各组小鼠气道反应性的变化,支气管肺泡灌洗液(BALF)中细胞总数和白细胞分类的变化以及支气管管壁厚度和支气管平滑肌厚度的变化;ELISA法检测MMP-2,MMP-9,TIMP-1水平;RT-PCR检测MMP-2,MMP-9,TIMP-1 mRNA的表达。结果显示,模型组气道反应性、BALF中细胞总数以及中性粒细胞、巨噬细胞、淋巴细胞和嗜酸性粒细胞计数、支气管管壁厚度和支气管平滑肌厚度明显高于正常组(P0.01),高剂量组和低剂量组与阳性对照组则明显低于模型组(P0.05或P0.01);模型组MMP-2,MMP-9和TIMP-1水平和mRNA表达明显高于正常组(P0.01),高剂量组和低剂量组与阳性对照组则明显低于模型组,差异具有统计学意义(P0.01)。推断中药川贝母可改善哮喘模型小鼠气道重塑状态,其机制可能与其降低MMP-2,MMP-9和TIMP-1有关。

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.