目的 探讨蛤蚧定喘胶囊（GJDC）通过调节“肠-肺”轴改善慢性阻塞性肺疾病（COPD）小鼠气道炎症的作用机制，验证其通过重塑肠道菌群-修复肠道屏障-抑制Toll样受体4（TLR4）/核因子（NF）-κB信号通路的跨器官调控机制。方法 72只SPF级雄性C57BL/6小鼠随机分为6组：对照组、模型组、地塞米松(Dex，阳性药，0.2 mg·kg^-1)组和GJDC高、中、低剂量(0.625、0.313、0.156 g·kg^-1)组，除对照组外，采用脂多糖（LPS）气管内滴注联合被动吸烟法建立COPD小鼠模型，造模结束后连续ig给药30 d。通过16S rRNA测序分析肠道菌群，肺组织苏木精-伊红（HE）染色、结肠阿利新蓝（AB）-H5IO6雪夫（PAS）染色观察组织病理学变化，酶联免疫吸附试验（ELISA）检测血清炎症因子LPS、肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1β、IL-6水平，qRT-PCR检测肠道屏障基因黏蛋白2（Muc2）、闭合小带(ZO)-1、紧密连接蛋白4（Claudin4）、肺组织炎症因子（TNF-α、IL-1β、IL-8）及TLR4/NF-κB信号通路基因（TLR4、MyD88、TRAF6）的mRNA表达。结果 与对照组比较，模型组小鼠表现出显著肺组织炎症损伤（肺泡间隔增宽、炎细胞浸润）、肠道菌群多样性下降（P<0.05）及肠屏障破坏（结肠杯状细胞减少，Muc2、ZO-1和Claudin4的mRNA表达显著性下调，P<0.05、0.01），伴随血清LPS和促炎因子TNF-α水平升高（P<0.05、0.01），肺组织中促炎因子TNF-α、IL-1β以及TLR4/NF-κB信号通路关键基因TLR4、TRAF6的mRNA表达水平均显著升高（P<0.05）；厚壁菌门（Firmicutes）的相对丰度显著升高，而拟杆菌门（Bacteroidota）的相对丰度显著降低（P<0.05）；毛螺菌科未分类属（norank_f__Lachnospiraceae）和阿克曼菌属（Akkermansia）的相对丰度显著降低（P<0.05），而拟杆菌属（Bacteroides）的相对丰度显著升高（P<0.05）。与模型组比较，GJDC干预后，中剂量组(0.313 g·kg^-1)效果最优，可显著恢复肠道菌群多样性及结构（P<0.05），增加拟杆菌门、产短链脂肪酸的毛螺菌科未分类属和黏液屏障调控菌阿克曼菌属的相对丰度（P<0.05、0.01）；修复肠道屏障功能（杯状细胞数量回升、Muc2、ZO-1、Claudin4表达上调），进而降低血清LPS及炎症因子水平（P<0.05、0.01、0.001），并显著抑制肺组织炎症、TLR4/NF-κB信号通路基因表达（P<0.05、0.01、0.001）。结论 GJDC通过重塑肠道菌群→修复肠道屏障→降低血清LPS→抑制肺TLR4/NF-κB信号通路的跨器官机制改善COPD炎症。

Objective To explore the mechanism by which Gejie Dingchuan Capsule（GJDC） alleviates airway inflammation in mice with chronic obstructive pulmonary disease（COPD） through the regulation of the ’gut-lung axis.’ The focus is on validating its crossorgan regulatory mechanism, which involves reshaping the gut microbiota, repairing the intestinal barrier, and inhibiting the TLR4/NF-κB signaling pathway. Methods 72 SPF male C57 BL/6 mice were randomly divided into 6 groups: control group, model group, dexamethasone(Dex, 0.2 mg·kg^-1) group, and GJDC high, medium and low dose(0.625, 0.313, 0.156 g·kg^-1) groups. Except for the control group, COPD mouse models were established by intratracheal instillation of lipopolysaccharide（LPS） combined with passive smoking. After modeling, the mice were continuously administered ig for 30 d. The intestinal flora was analyzed by 16S rRNA sequencing. The histopathological changes of lung tissue were observed by hematoxylin-eosin（HE） staining and colon Alcian blue（AB）-periodic acid-Schiff（PAS） staining. The levels of serum inflammatory factors LPS, tumor necrosis factor（TNF）-α, interleukin（IL）-1β, and IL-6 were detected by enzyme-linked immunosorbent assay（ELISA）. The mRNA expression of intestinal barrier genes mucin 2（Muc2）, zonula occludens(ZO)-1, tight junction protein 4（Claudin4）, inflammatory factors in lung tissue（TNF-α, IL-1β, IL-8）, and TLR4/NF-κB signaling pathway genes（TLR4, My D88, TRAF6） was detected by qRT-PCR. Results Compared with the control group, the model group showed significant lung tissue inflammatory injury（alveolar septal widening, inflammatory cell infiltration）, decreased intestinal flora diversity（P ＜ 0.05）, and intestinal barrier damage（reduced colonic goblet cells, significant down-regulation of Muc2, ZO-1 and Claudin4 mRNA expression, P ＜ 0.05, 0.01）, accompanied by increased serum LPS and pro-inflammatory factor TNF-α levels（P ＜ 0.05, 0.01）, and significantly increased mRNA expression levels of pro-inflammatory factors TNF-α, IL-1β and TLR4/NF-κB signaling pathway key genes TLR4 and TRAF6 in lung tissue（P ＜ 0.05）; The relative abundance of Firmicutes significantly increased, while the relative abundance of Bacteroidota significantly decreased（P ＜ 0.05）; The relative abundance of unclassified genus norank_f__Lachnospiraceae and Akkermansia significantly decreased（P ＜ 0.05）, while the relative abundance of Bacteroides significantly increased（P ＜ 0.05）. Compared with the model group, the medium-dose group(0.313 g·kg^-1) of GJDC intervention had the best effect, which could significantly restore intestinal flora diversity and structure（P ＜ 0.05）, increase the relative abundance of Bacteroidota, unclassified genus norank_f__Lachnospiraceae producing short-chain fatty acids, and Akkermansia regulating the mucus barrier（P ＜ 0.05, 0.01）; Repair intestinal barrier function（increase in goblet cell number, up-regulation of Muc2, ZO-1, and Claudin4 expression）, thereby reducing serum LPS and inflammatory factor levels（P ＜ 0.05, 0.01, 0.001）, and significantly inhibit lung tissue inflammation and TLR4/NF-κB signaling pathway gene expression（P ＜ 0.05, 0.01, 0.001）. Conclusion GJDC improves COPD inflammation through a cross-organ mechanism of reshaping intestinal flora → repairing intestinal barrier → reducing serum LPS → inhibiting the lung TLR4/NF-κB signaling pathway.

R285.5

广西科技重大专项(桂科AA23023035-4); 桂林市重点研发计划资助项目(市科2023010302-1)