【摘要】 目的 探讨高迁移率族蛋白B1(high mobility group box??1 protein,HMGB1)调控NOD样受体蛋白3(NOD??like receptor protein 3,NLRP3)炎性小体介导肺炎支原体感染小鼠气道黏液高分泌的作用机制。方法 选取40只6～8周龄SPF级C57BL/6小鼠，随机分为对照组、模型组、甘草酸（一种HMGB1抑制剂）干预组和MCC950（一种NLRP3炎症小体特异性抑制剂）干预组。建立肺炎支原体感染小鼠模型，采用Western blot检测肺组织NLRP3、凋亡相关斑点样蛋白（apoptosis??associated speck??like protein containing a CARD, ASC）、半胱天冬酶??1(caspase??1)、消皮素D(gasdermin D, GSDMD)及其N端片段（GSDMD??N）以及支气管肺泡灌洗液（bronchoalveolar lavage fluid,BALF）中HMGB1和MUC5AC的蛋白表达水平；过碘酸??希夫染色（periodic acid??Schiff staining,PAS）观察杯状细胞增生与黏液分泌；免疫组化染色分析MUC5AC和NLRP3的定位与表达；ELISA检测血清白细胞介素??1β(interleukin??1β,IL??1β)和白细胞介素??18(interleukin??18,IL??18)水平。结果 与对照组相比，模型组肺组织NLRP3、ASC、caspase??1、GSDMD??N及BALF中HMGB1、MUC5AC蛋白表达均显著升高，差异均有统计学意义（均P<0.05），血清IL??1β、IL??18水平均明显上升，差异均有统计学意义（P<0.001）；甘草酸干预组和MCC950干预组上述指标均显著下降，差异均有统计学意义（均P<0.05）。PAS与免疫组化结果显示，模型组杯状细胞增生及黏液分泌显著增加，干预后明显改善。结论结论 HMGB1通过激活NLRP3炎性小体及其下游caspase??1/GSDMD通路，促进IL??1β、IL??18释放与MUC5AC表达，介导肺炎支原体感染小鼠气道黏液高分泌；靶向抑制HMGB1或NLRP3可有效缓解该病理状态，可为临床防治肺炎支原体肺炎提供潜在新靶点。更多还原

【Abstract】 Objective: To investigate the mechanism by which high mobility group box-1(HMGB1) regulates the NODlike receptor protein 3(NLRP3) inflammasome in mediating airway mucus hypersecretion in mice infected with Mycoplasma Pneumoniae(MP). Methods: Forty specific pathogen-free(SPF) C57 BL/6 mice, aged 6-8 weeks, were randomly assigned to four groups: normal control(NC), MP infection(MPP), glycyrrhizic acid intervention(GA), and MCC950 intervention. An MP-infected mouse model was established. The protein expression levels of NLRP3, ASC, Caspase-1, and GSDMD-N in lung tissue, as well as HMGB1 and MUC5 AC in bronchoalveolar lavage fluid(BALF), were detected by Western blot. Goblet cell hyperplasia and mucus secretion were assessed via periodic acid-Schiff(PAS) staining. The localization and expression of MUC5 AC and NLRP3 were analyzed by immunohistochemistry. Serum levels of IL-1β and IL-18 were measured using enzyme-linked immunosorbent assay(ELISA). Results: Compared with the NC group, the MPP group exhibited significantly increased protein expression of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, HMGB1, and MUC5 AC(all P < 0. 05), alongside markedly elevated serum levels of IL-1β and IL-18(P < 0. 001). These indicators were significantly reduced in both the GA and MCC950 intervention groups(all P < 0. 05). PAS and immunohistochemistry results demonstrated substantial goblet cell hyperplasia and mucus secretion in the MPP group, which were notably ameliorated following intervention. Conclusion: HMGB1 promotes airway mucus hypersecretion in MP-infected mice by activating the NLRP3 inflammasome and its downstream caspase-1/GSDMD pathway, leading to the release of IL-1β and IL-18 and the overexpression of MUC5 AC. Targeted inhibition of either HMGB1 or NLRP3 effectively alleviates this pathological state, suggesting a potential novel therapeutic strategy for MP pneumonia.更多还原