Department of Immunology and Microbiology, School of Life Sciences, Beijing University of Chinese Medicine, No. 11 North Three-ring East Road, Chao Yang District, Beijing 100029, China.
Department of Immunology and Microbiology, School of Life Sciences, Beijing University of Chinese Medicine, No. 11 North Three-ring East Road, Chao Yang District, Beijing 100029, China.
Phytomedicine. 2024 Jun;128:155446. doi: 10.1016/j.phymed.2024.155446. Epub 2024 Feb 10.
Influenza viral pneumonia is a common complication after influenza virus infection. Xijiao Dihuang Decoction combined with Yinqiao Powder (XDY) is effective on improving influenza viral pneumonia.
This study further explores the anti-inflammatory mechanism of XDY in the treatment of influenza viral pneumonia.
The effects of XDY on inflammation, autophagy, NACHT-LRR-PYD-containing protein 3 (NLRP3) inflammasome and pyroptosis were assessed in the mice with influenza viral pneumonia. In addition, the mouse macrophage cell line (J774A.1) infected with influenza virus was adopted to decode the in vitro effects of XDY on autophagy, reactive oxygen species (ROS), NLRP3 inflammasome and pyroptosis. We analyzed the XDY-induced autophagy, especially the mitophagy-related ROS clearance, and the subsequent inhibition of ROS/NLRP3 inflammasome/pyroptosis signaling in the infected macrophages by different assays based on quantitative polymerase chain reaction, western blot, flow cytometry, immunofluorescence and enzyme-linked immunosorbent assay.
In vivo, XDY could effectively improve the lung inflammatory response in the mice with influenza virus pneumonia, due to an intact autophagy flux-promoting effect and the inhibiting roles on NLRP3 inflammasome and pyroptosis. Notably, in vitro, compared with the infected macrophages treated by the NLRP3 inflammasome agonist (Monosodium urate) or the mitochondrial-targeted antioxidant agent, the XDY-dependent treating could inhibit pyroptosis by negatively regulating the signaling axis of ROS/NLRP3 inflammasome/pyroptosis in the influenza virus-infected macrophages. More interestingly, XDY could promote an intact autophagy flux, inducing mitophagy eliminating the damaged mitochondria to reduce the intracellular ROS accumulation, and thus decrease the oxidative stress in the infected macrophages. Especially, the inhibitor of autophagy inition, 3-Methyladenine, could reverse the inhibitory effect of XDY on ROS-NLRP3 inflammasome-mediated pyroptosis, indicating an XDY-promoted mitophagy-dependent ROS scavenging.
XDY can promote an intact autophagy flux to eliminate damaged mitochondria, namely mitophagy, which reduces the intracellular ROS accumulation contributing to NLRP3 inflammasome activation, restricting pyroptosis and eventually alleviating the influenza virus-induced inflammatory lesions. The obtained results provide new insights into the mechanism of action of XDY in alleviating influenza virus pneumonia, especially the roles of XDY in anti-oxidation, anti-inflammation and anti-pyroptosis, with potential therapeutic targets for future application in integrative medicine.
流感病毒性肺炎是流感病毒感染后的常见并发症。银翘解毒汤联合银翘散（XDY）对改善流感病毒性肺炎具有疗效。
本研究进一步探讨 XDY 治疗流感病毒性肺炎的抗炎机制。
在流感病毒性肺炎小鼠模型中评估 XDY 对炎症、自噬、含 NACHT-LRR-PYD 结构域的蛋白 3（NLRP3）炎性小体和细胞焦亡的影响。此外，采用流感病毒感染的小鼠巨噬细胞系（J774A.1），解析 XDY 对自噬、活性氧（ROS）、NLRP3 炎性小体和细胞焦亡的体外作用。我们通过定量聚合酶链反应、western blot、流式细胞术、免疫荧光和酶联免疫吸附试验等不同检测方法，分析 XDY 诱导的自噬，特别是线粒体自噬相关的 ROS 清除，以及随后在感染的巨噬细胞中抑制 ROS/NLRP3 炎性小体/细胞焦亡信号通路。
体内实验中，XDY 可有效改善流感病毒肺炎小鼠的肺部炎症反应，这归因于完整的自噬流促进作用以及对 NLRP3 炎性小体和细胞焦亡的抑制作用。值得注意的是，体外实验中，与 NLRP3 炎性小体激动剂（尿酸单钠）或线粒体靶向抗氧化剂处理的感染巨噬细胞相比，XDY 依赖性治疗可通过负调控 ROS/NLRP3 炎性小体/细胞焦亡信号通路来抑制细胞焦亡。更有趣的是，XDY 可促进完整的自噬流，诱导线粒体自噬清除受损的线粒体，从而减少细胞内 ROS 积累，降低感染巨噬细胞的氧化应激。特别是，自噬抑制物 3-甲基腺嘌呤可逆转 XDY 对 ROS-NLRP3 炎性小体介导的细胞焦亡的抑制作用，表明 XDY 促进的线粒体自噬依赖性 ROS 清除。
XDY 可促进完整的自噬流以清除受损的线粒体，即线粒体自噬，从而减少细胞内 ROS 积累，有助于 NLRP3 炎性小体激活，限制细胞焦亡，最终减轻流感病毒引起的炎症损伤。研究结果为 XDY 缓解流感病毒性肺炎的作用机制提供了新的见解，特别是 XDY 在抗氧化、抗炎和抗细胞焦亡中的作用，为未来综合医学的应用提供了潜在的治疗靶点。
