目的 基于NOD样受体蛋白3（NLRP3）炎症小体与细胞焦亡，探究金合欢素对急性肺损伤（ALI）的治疗作用。方法 将雄性C57BL/6J小鼠适应性喂养1周后，随机分为对照组、模型组、金合欢素（40 mg·kg^-1）组，除对照组外，ip致死剂量的脂多糖（LPS，20 mg·kg^-1）构建ALI小鼠模型，进行小鼠生存率实验； ip致炎剂量的LPS（10 mg·kg^-1）构建ALI小鼠模型，苏木素-伊红（HE）染色法检测肺组织病理变化；实时荧光定量PCR（qRT-PCR）法检测小鼠肺组织炎症相关基因肿瘤坏死因子（Tnf）、白细胞介素（Il） 6、Il1b的表达； Western blotting检测小鼠肺组织中NLRP3通路相关蛋白NLRP3、消皮素D（GSDMD）的表达； ELISA法检测小鼠腹腔灌洗液IL-1β水平。体外培养原代腹腔巨噬细胞，通过将LPS分别与腺嘌呤核苷三磷酸（ATP）、尼日利亚菌素（Nig）以及短杆菌肽（Gram）联合使用，刺激NLRP3炎症小体激活，给予金合欢素（5、10、20 μmol·L-1）联合培养，Western blotting法检测半胱氨酸蛋白酶-1（Caspase-1）、NLRP3、GSDMD蛋白表达水平，碘化丙啶（PI）/Hoechst染色观察细胞焦亡。结果 LPS 20 mg·kg^-1造模后45 h，模型组小鼠全部死亡；金合欢素组小鼠最终生存率为60%。与LPS 10 mg·kg^-1模型组相比，金合欢素组的小鼠肺组织结构损伤得到显著缓解，炎症细胞浸润明显减少，肺泡壁增厚情况减轻，且肺组织损伤评分显著降低（P＜0.001）；肺组织Tnf、Il6、Il1b mRNA表达显著下降（P＜0.001），腹腔灌洗液IL-1β水平显著降低（P＜0.001）；肺组织NLRP3、GSDMD-NT蛋白表达水平明显降低（P＜0.01、0.001）。体外实验结果表明，与模型组比较，金合欢素组NLRP3、GSDMD-NT、Caspase-1（p20）蛋白表达水平显著降低（P＜0.01、0.001）；细胞焦亡率显著降低（P＜0.001）。结论 金合欢素可以通过抑制NLRP3炎症小体与细胞焦亡，改善ALI小鼠的肺部损伤以及炎症反应。

Objective To investigate the therapeutic effects of acacetin on acute lung injury (ALI) base on the NOD-like receptor protein 3 (NLRP3) inflammasome and pyroptosis. Methods Male C57BL/6J mice were adaptively fed for one week and then randomly divided into control group, model group, and acacetin (40 mg·kg^-1) group. Except for control group, the mice in the other groups were ip with a lethal dose of lipopolysaccharide (LPS, 20 mg·kg^-1) to establish ALI mouse model, and the survival rate of the mice was examined. The mice in the other groups were ip with an inflammatory dose of LPS (10 mg·kg^-1) to establish the ALI mouse model. The pathological changes of lung tissue were detected by hematoxylin-eosin (HE) staining. The expression of inflammationrelated genes tumor necrosis factor (Tnf), interleukin (Il) 6, and Il1b in lung tissue was detected by real-time fluorescence quantitative PCR (qRT-PCR). The expression of NLRP3 pathway-related proteins NLRP3 and gasdermin D (GSDMD) in lung tissue was detected by Western blotting. The level of IL^-1β in the peritoneal lavage fluid was detected by ELISA. Primary peritoneal macrophages were cultured in vitro. LPS was combined with adenosine triphosphate (ATP), nigericin (Nig), and gramicidin (Gram) to stimulate the activation of NLRP3 inflammasome. Acacetin (5, 10, 20 μmol·L^-1) was added for co-culture. The expression levels of caspase-1, NLRP3, and GSDMD proteins were detected by Western blotting, and pyroptosis was observed by propidium iodide (PI)/Hoechst staining. Results 45 h after LPS 20 mg·kg^-1 modeling, all mice in the model group died; The final survival rate of the acacetin group was 60%. Compared with LPS 10 mg·kg^-1 model group, the structural damage of lung tissue in the acacetin group was significantly alleviated, the infiltration of inflammatory cells was significantly reduced, the thickening of alveolar walls was alleviated, and the lung tissue injury score was significantly decreased (P < 0.001); The mRNA expression of Tnf, Il6, and Il1b in lung tissue was significantly decreased (P < 0.001), and the level of IL^-1β in peritoneal lavage fluid was significantly decreased (P < 0.001); The expression levels of NLRP3 and GSDMD-NT proteins in lung tissue were significantly decreased (P < 0.01, 0.001). The in vitro experimental results showed that compared with the model group, the expression levels of NLRP3, GSDMD-NT, and Caspase-1 (p20) proteins in the acacetin group were significantly decreased (P < 0.01, 0.001), and the pyroptosis rate was significantly decreased (P < 0.001). Conclusion Acacetin has the potential to ameliorate lung injury and modulate the inflammatory response in ALI mice by suppressing the NLRP3 inflammasome and pyroptosis.

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国家自然科学基金面上项目（82474153）;北京中医药大学-优莎纳联合研究中心（BURC）基金重点项目（ BUCM-2022-JS-KF-003）;北京市科技新星计划课题（20230484342）;北京市自然科学基金资助项目（7242239）;中华中医药学会青年人才托举工程项目(CACM-2023-QNRC2-A02)