大蒜素调控JAK2/STAT3通路对肺结核大鼠肺部炎症影响的研究

Effects of Allicin Regulating JAK2/STAT3 Pathway on Pulmonary Inflammation in Pulmonary Tuberculosis Rats

目的:探讨大蒜素调控Janus激酶2(JAK2)/信号转导和转录激活因子3(STAT3)通路对肺结核大鼠肺部炎症的影响。方法:以尾静脉注射结核杆菌悬液的方法构建肺结核大鼠模型,随机分为:模型组、大蒜素组(14 mg·kg^(-1))、AG490组(JAK抑制剂,5 mg·kg^(-1))、大蒜素+AG490组(14 mg·kg^(-1)+5 mg·kg^(-1)),每组12只,另选12只大鼠作为正常对照组。各给药组灌胃给与相应药物,模型组和正常对照组给与等量0.9%氯化钠溶液,1次/d,持续21 d。以药物分组干预处理后,测定各组肺组织结核分枝杆菌菌落数;苏木精-伊红(HE)染色检测各组大鼠肺组织病理学变化;试剂盒检测各组大鼠肺组织氧化应激因子谷胱甘肽过氧化物酶(GSH-Px)、活性氧(ROS)、丙二醛(MDA)水平及血清炎症因子γ干扰素(IFN-γ)、白细胞介素-6(IL-6)、环氧化酶-2(COX-2)水平;免疫印记法检测各组大鼠肺组织JAK2/STAT3通路相关蛋白表达。结果:与正常对照组相比,模型组大鼠肺组织可见大量增生型结核结节,肺组织炎症细胞浸润明显,肺泡管、肺泡腔异常扩大,出现干酪样坏死等病理损伤,肺组织结核分枝杆菌菌落数、ROS与MDA水平、血清炎症因子IFN-γ、IL-6与COX-2水平、肺组织p-JAK2/JAK2及p-STAT3/STAT3显著升高(P<0.05),肺组织GSH-Px水平显著降低(P<0.05)。与模型组相比,大蒜素组、AG490组、大蒜素+AG490组大鼠肺组织上述病理损伤均有改善,肺组织结核分枝杆菌菌落数、ROS与MDA水平、血清炎症因子IFN-γ、IL-6与COX-2水平、肺组织p-JAK2/JAK2及p-STAT3/STAT3均降低(P<0.05),肺组织GSH-Px水平均升高(P<0.05);与大蒜素组、AG490组分别相比,大蒜素+AG490组大鼠肺组织上述病理损伤改善程度增加,肺组织结核分枝杆菌菌落数、ROS与MDA水平、血清炎症因子IFN-γ、IL-6与COX-2水平、肺组织p-JAK2/JAK2及p-STAT3/STAT3均降低(P<0.05),肺组织GSH-Px水平均升高(P<0.05)。结论:大蒜素可抑制炎症,降低氧化应激水平,改善肺结核大鼠肺部病理损伤,可能是通过下调JAK2/STAT3通路信号实现的。

Objective:To investigate the effects of allicin regulating Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3) pathway on lung inflammation in pulmonary tuberculosis rats.Methods:The pulmonary tuberculosis rat model was constructed by injecting mycobacterium tuberculosis suspension into tail vein,and the rats were randomly divided into model group,allicin group(14 mg·kg^(-1)),AG490 group(JAK inhibitor,5 mg·kg^(-1)) and allicin+AG490 group(14 mg·kg^(-1)+5 mg·kg^(-1)) with 12 rats in each group.Another 12 rats were selected as normal control group.Each administration group was given corresponding drug by gavage,and the model group and normal control group were given the same amount of 0.9% NaCl solution,once a day for 21 days.After intervention with drugs,the number of colonies of mycobacterium tuberculosis in lung tissues of each group was determined;the pathological changes in lung tissues of rats in each group were detected with hematoxylin-eosin(HE) staining;the levels of oxidative stress factors glutathione peroxidase(GSH-Px),reactive oxygen species(ROS),malondialdehyde(MDA) and serum levels of inflammatory factors interferon-γ(IFN-γ),interleukin-6(IL-6) and cyclooxygenase 2(COX-2) in lung tissues of rats in each group were detected by kits;the expression of JAK2/STAT3 pathway related proteins in lung tissues of rats in each group was detected by immunoblotting method.Results:Compared with the normal control group,a large number of proliferative tuberculosis nodules were seen in lung tissue of the model group,the inflammatory cell infiltration in lung tissue was obvious,the alveolar ducts and alveolar cavity were abnormally enlarged,and pathological damages such as caseous necrosis occurred,the number of colonies of mycobacterium tuberculosis in lung tissue,levels of ROS and MDA,levels of serum inflammatory factors IFN-γ,IL-6 and COX-2,lung tissue p-JAK2/JAK2 and p-STAT3/STAT3 were significantly increased(P<0.05),and the level of GSH-Px in lung tissue was significantly reduced(P<0.05).Compared with the model group,the above-mentioned pathological damages in lung tissues of rats in allicin group,AG490 group and allicin+AG490 group were all improved,the number of colonies of mycobacterium tuberculosis in lung tissue,levels of ROS and MDA,levels of serum inflammatory factors IFN-γ,IL-6 and COX-2,lung tissue p-JAK2/JAK2 and p-STAT3/STAT3 were reduced(P<0.05),and the level of GSH-Px in lung tissue was increased(P<0.05).Compared with allicin group and AG490 group,the improvement of above-mentioned pathological damage in lung tissue of allicin+AG490 group was increased,the number of colonies of mycobacterium tuberculosis in lung tissue,levels of ROS and MDA,levels of serum inflammatory factors IFN-γ,IL-6 and COX-2,lung tissue p-JAK2/JAK2 and p-STAT3/STAT3 were reduced(P<0.05),and the level of GSH-Px in lung tissue was increased(P<0.05).Conclusion:Allicin can inhibit inflammation,reduce the level of oxidative stress,and improve lung pathological damage in pulmonary tuberculosis rats,which may be achieved by down-regulating JAK2/STAT3 signal pathway.