美罗培南调控JAK2-STAT3-RORyt通路对慢性阻塞性肺疾病大鼠气道重塑的影响

Effect of meropenem on airway remodeling in rats with chronic obstructive pulmonary disease by regulating JAK2-STAT3-RORyt pathway

目的:探讨美罗培南(MEP)对慢性阻塞性肺疾病(COPD)大鼠气道重塑的影响及对JAK2-STAT3-RORyt信号通路的调控作用。方法:将40只大鼠随机分为对照组、COPD组、COPD+MEP组和JAK2抑制剂组,每组10只。除对照组外,其余各组复制COPD大鼠模型。COPD+MEP组造模后经臀肌肌肉注射20 mg/kg的MEP,JAK2抑制剂组造模后经臀肌肌肉注射8 mg/kg的AG490。比较各组用力肺活量(FVC)与第0.3秒用力呼气量(FEV_(0.3))的比值。采用苏木精—伊红(HE)染色观察肺组织病理形态学改变,分析支气管肺泡灌洗液(BALF)总细胞、中性粒细胞,淋巴细胞和巨噬细胞数量,酶联免疫吸附试验(ELISA)法测定肺组织白细胞介素(IL)-6、IL-8、肿瘤坏死因子(TNF)-α和IL-1β的含量。分别采用实时荧光定量PCR(RT-qPCR)和west-ern blotting检测转化生长因子-β1(TGF-β1)、Ⅰ型胶原(collagenⅠ)、α-平滑肌肌动蛋白(α-SMA)、JAK2、STAT3、RORyt mRNA及蛋白表达。结果:与对照组相比,COPD组大鼠体重和FEV_(0.3)/FVC下降,collagenⅠ、α-SMA、TGF-β1、JAK2、STAT3和ROR-yt mRNA及蛋白表达水平升高,BALF中总细胞、巨噬细胞、中性粒细胞和淋巴细胞数量增多,肺组织IL-8、IL-6、TNF-α和TGF-β1含量升高(均P<0.05)。HE染色显示,COPD组气道黏膜褶皱增多、延长,气管及血管周围大量炎症细胞聚集成团,平滑肌增厚。与COPD组相比,COPD+MEP组和JAK2抑制剂组JAK2、STAT3和RORyt mRNA及蛋白表达水平降低,BALF中总细胞、巨噬细胞、中性粒细胞和淋巴细胞数量减少,肺组织IL-8、IL-6、TNF-α和TGF-β1含量降低(均P<0.01)。结论:MEP可通过抑制JAK2-STAT3-RORyt信号通路及肺部炎症减轻COPD大鼠气道重塑。

Objective:To investigate the effect of meropenem(MEP)on airway remodeling in rats with chronic obstructive pulmonary disease(COPD)and its regulatory effect on JAK2-STAT3-RORyt signaling pathway.Methods:Forty rats were randomly divided into control group,COPD group,COPD+MEP group and JAK2 in-hibitor group,with 10 rats in each group.Except for the control group,the COPD rat model was reproduced in the other groups.After establishing the model,the COPD+MEP group received an intramuscular injection of 20 mg/kg MEP into the gluteal muscle,while the JAK2 inhibitor group received an intramuscular injection of 8 mg/kg AG490 into the gluteal muscle.The ratio of forced vital capacity(FVC)to forced expiratory volume in 0.3 sec-ond(FEV_(0.3))in each group was compared.Hematoxylin-eosin(HE)staining was used to observe the pathomor-phological changes of lung tissue.The number of total cells,neutrophils,lymphocytes and macrophages in bron-choalveolar lavage fluid(BALF)was analyzed.The contents of interleukin(IL)-6,IL-8,tumor necrosis factor(TNF)-αand IL-1βin lung tissue were determined by enzyme-linked immunosorbent assay(ELISA).The mRNA and protein expression of transforming growth factor-β1(TGF-β1),collagenⅠ,α-smooth muscle actin(α-SMA),JAK2,STAT3 and RORyt was detected by real-time fluorescence quantitative PCR(RT-qPCR)and western blotting,respectively.Results:Compared with the control group,the body weight and FEV_(0.3)/FVC of the COPD group were decreased,the mRNA and protein expression levels of collagenⅠ,α-SMA,TGF-β1,JAK2,STAT3 and RORyt were increased,and the number of total cells,macrophages,neutrophils and lymphocytes in BALF was increased.The contents of IL-8,IL-6,TNF-αand TGF-β1 in lung tissue were increased(all P<0.05).HE staining showed that the airway mucosal folds were increased and prolonged,a large number of inflammatory cells clustered around the trachea and blood vessels,and the smooth muscle thickened in the COPD group.Compared with the COPD group,the COPD+MEP group and the JAK2 inhibitor group had lower mRNA and protein expression levels of JAK2,STAT3 and RORyt,and a lower number of total cells,macrophages,neutrophils and lymphocytes in BALF.The contents of IL-8,IL-6,TNF-αand TGF-β1 in lung tissue were decreased(all P<0.01).Conclusion:MEP can al-leviate airway remodeling in COPD rats by inhibiting JAK2-STAT3-RORyt signaling pathway and pulmonary in-flammation.