地塞米松可增强支气管哮喘小鼠肺组织RECK的表达

Dexamethasone increases the expression of reversion-inducing cysteine-rich protein with Kazal motifs( RECK) in lung tissues of bronchial asthmatic mice

目的研究Kazal基序逆向诱导富含半胱氨酸蛋白(RECK)在支气管哮喘小鼠肺组织的表达及地塞米松处理后对其表达的影响。方法 BALB/c小鼠分为哮喘组、对照组、地塞米松组,每组10只。采用鸡卵清蛋白(OVA)腹腔注射致敏及雾化吸入的方法制作哮喘模型,进行支气管肺泡灌洗液(BALF)中嗜酸性粒细胞(EOS)及淋巴细胞(Lym)分类计数;HE染色观察气道炎症细胞浸润及气道重塑情况,实时荧光定量PCR检测RECK mRNA的表达,免疫组织化学法检测RECK蛋白的表达及定位。结果与对照组和地塞米松组相比,哮喘组BALF中细胞总数、EOS明显增多;RECK mRNA在哮喘组表达较对照组、地塞米松组明显降低。免疫组织化学结果显示RECK主要表达于气道上皮细胞、上皮下炎症细胞。哮喘组表达最低,对照组表达最高,地塞米松组表达较哮喘组有所增高。结论 RECK在哮喘小鼠肺组织中表达明显降低,而地塞米松可上调RECK的表达。

Objective To investigate the expression of reversion-inducing cysteine-rich protein with Kazal motifs （RECK） in the lung tissues of bronchial asthmatic mice and the effect of dexamethasone treatment on its expression. Methods Thirty BALB/c mice were randomly divided into three equal groups： a control group, an asthmatic group and a dexamethasone- treated group. The asthmatic mouse models were established by intraperitoneal injection and inhalation with ovalbumin （OVA）. The number of eosinophils （EOS） and lymphocytes （Lym） in bronchoalveolar lavage fluid （BALF） were counted. HE staining was used to observe airway inflammation and remodeling. The mRNA and protein expression of RECK were determined by real-time PCR and immunohistochemistry, respectively. Results Compared with the control group and the dexamethasone-treated group, the total cell number and EOS number in the BALF of the asthma group significantly increased. The expression of RECK mRNA in the asthmatic group was significantly lower than that in the control group and the dexamethasone-treated group. Immunohistochemistry showed that RECK was mainly expressed in the airway epithelial cells and inflammatory cells. RECK protein expression was highest in the control group and lowest in the asthmatic group. Conclusion Dexamethasone can increase the expression of RECK in the lung tissues of asthmatic mice.