CCL20和MMP-9在COPD大鼠中的表达及多西环素对其表达的影响

Expression of CCL20 and MMP-9 in COPD rats and the effect of doxycycline on it

目的探讨慢性阻塞性肺疾病(COPD)大鼠模型中巨噬细胞炎症蛋白-3α(CCL20)和基质金属蛋白酶9(MMP-9)的表达水平及多西环素对表达的影响。方法 Wistar雄性大鼠24只随机分为3组:健康对照组、COPD模型组、多西环素干预组。40天造模完成后,HE染色观察各组大鼠肺组织的病理改变,酶联免疫吸附实验(ELISA)检测支气管肺泡灌洗液(BALF)中CCL20、MMP-9的含量,免疫组化法观察肺组织内CCL20、MMP-9的蛋白表达情况。结果模型组及干预组气管、支气管及肺组织中出现慢性气管炎、阻塞性肺气肿的特征性病理改变,符合人类COPD的特点。光镜下模型组肺泡管、肺泡囊和肺泡明显扩张,肺泡壁变薄并有不同程度的断裂;干预组大鼠肺泡壁断裂和肺泡腔扩张情况较模型组明显减轻。与对照组比较,模型组、干预组肺泡灌洗液(BALF)中CCL20、MMP-9的含量显著增高,差异有统计学意义(P<0.05)。与模型组比较,干预组BALF中CCL20含量差异无统计学意义(P>0.05);MMP-9的含量显著降低,差异有统计学意义(P<0.05)。与对照组比较,模型组、干预组肺组织中CCL20、MMP-9蛋白表达明显增强(P<0.05)。与模型组比较,干预组肺组织中CCL20蛋白表达差异无统计学意义(P>0.05);MMP-9蛋白表达明显减弱(P<0.05)。结论 CCL20可能通过免疫反应参与COPD持续的慢性炎症过程;多西环素可能通过调节MMP-9的表达,减轻肺气肿时肺泡壁的破坏,发挥阻止COPD进展的作用。

Objective To investigate the expression of macrophage inflammatory protein-3α （CCL-20） and matrix metalloproteinase-9 （MMP-9） in the chronic obstructive pulmonary disease （COPD） in Wistar rats model, and the influence of doxycycline on it. Methods Twenty-four male Wistar rats were randomly divided into three groups： the normal control group, the model group, the intervention group. At the end of forty days, when COPD model was established, histological changes of lung tissue were observed with HE staining. The bronchoalveolar lavage fluid （BALF） concentration of CCL-20 and MMP-9 were detected by enzyme-linked immunosorbent assay （ELISA）. The protein expressions of CCL-20 and MMP-9 in lung tissue were detected by immunohistochemistry method. Results The rats of model group and the doxycycline group shared specific pathological features in trachea, bronchi and lung tissues with those of human chronic bronchitis and obstructive emphysema. The light-microscopy HE dyeing slice showed the model group with alveolar ducts and alveolar sac and alveolar obvious expansion, alveolar walls thinning and had different degrees of fracture. The brokenness of alveolar walls and the expand of alveolar cavity in the intervention group were more alleviatory than those in the model group. Compared with the normal control group, the level of CCL-20 and MMP-9 in BALF of model and intervention group increased significantly （ P 〈 0.05 ） ; Compared with model group, intervention group CCL-20 content in BALE had no significant difference （ P 〉 0. 05 ） ; MMP-9 levels decreased significantly, the difference was statistically significant （P 〈 0.05）. Compared with control group, the expression of CCL-20 and MMP-9 in the lung tissues in model group and intervention group was obviously increased （P 〈 0.05） ; Compared with model group, CCL-20 expression in lung tissue had no significant difference in intervention group （P 〉 0.05 ） ; but MMP-9 expression decreased significantly （ P 〈 0.05 ）. Conclusion CCL20 may perticipate in COPD continuous chronic inflammation process through immune response; Doxycycline may play the role of preventing COPD progress by regulating MMP-9 expression and lessening the degradation of extraecllular matrix of alveolar wall when emphysema happened.