Objectives: To explore the therapeutic mechanism of Arctium lappa extract for treatment of Post-Viral Pneumonia Pulmonary Fibrosis (PPF).
Methods: The chemical constituents of Arctium lappa extracts were identified using UHPLC-Q-TOF-MS/MS. Mouse models of pulmonary fibrosis established by tracheal instillation of bleomycin were treated with Arctium lappa extract, and body weight changes were recorded and lung tissue pathology was examined using HE and Masson staining. Metabolomics analysis was used to identify the differential metabolites and the associated metabolic pathways in the treated mice. The common targets of viral pneumonia and pulmonary fibrosis were acquired from the publicly available databases, and the core targets and active constituents were screened using the protein-protein interaction (PPI) network, GO and KEGG enrichment analyses, and molecular docking, and a "gene-metabolite" regulatory network was constructed. The expressions of the core targets were detected in the lung tissues of the treated mice using Western blotting.
Results: Fifty-three chemical constituents were identified from Arctium lappa extract. In the mouse models of pulmonary fibrosis, treatment with Arctium lappa extract significantly improved weight loss and ameliorated lung inflammation and fibrosis. The differential metabolites in the treated mice were enriched in energy metabolism pathways involving citrate cycle, pentose phosphate pathway, glycolysis, tryptophan metabolism, glutamate metabolism and glutathione metabolism, which regulated the production of energy metabolism intermediates. Twenty-three key active compounds (mostly lignans and phenolic acids) and 82 core targets were screened, which were associated with the non-canonical Smad signaling pathways (including PI3K/AKT, HIF-1, MAPK, and Foxo) that participated in the regulation of energy metabolism. Arctium lappa extract also regulated the expressions of epithelial-mesenchymal transition (EMT)‑related proteins (fibronectin, vimentim, and Snail, etc.) and inhibited MAPK signaling pathway activation.
Conclusions: Preliminary findings suggest that Arctium lappa treats fibrosis by regulating metabolism to inhibit EMT and involves the modulation of non-canonical Smad signaling pathways, such as MAPK providing theoretical support for its clinical application and further research in treating PPF.
目的: 应用代谢组学、网络药理学及实验验证探究牛蒡子治疗病毒性肺炎后肺纤维化（PPF）的作用机制。方法: 采用UHPLC-Q-TOF-MS/MS技术鉴定牛蒡子提取物化学成分，SPF级小鼠随机分为4组，8只/组，分别为空白组（Ctrl）、模型组（BLM）、AL低剂量组（ALL）、AL高剂量组（ALH）。采用博来霉素气管给药模式建立小鼠肺纤维化模型，给予牛蒡子治疗后，记录体质量变化、观察HE及MASSON染色的肺组织病理变化。通过代谢组学分析筛选差异代谢物及相关代谢通路。基于OMIM、TTD、Gene Cards等数据库获取病毒性肺炎与肺纤维化的共同靶点，通过PPI、GO、KEGG富集分析及分子对接筛选核心靶点和有效成分，并构建“基因-代谢物”调控网络；Western blotting技术检测相关基因信号蛋白表达水平。结果: 鉴定出牛蒡子化学成分53个，牛蒡子可显著改善肺纤维化小鼠的体质量下降、肺组织炎症浸润（P<0.05）以及纤维化（P<0.05）。差异代谢物主要富集在柠檬酸代谢、磷酸戊糖途径、糖酵解途径、色氨酸代谢、谷氨酸代谢、谷胱甘肽途径等能量代谢途径，调控了能量代谢途径中间产物的产量。筛选出23个关键活性成分（以木脂素、酚酸等为主）和82个核心靶点，涉及PI3K/AKT、HIF-1、MAPK、Foxo等非经典Smad信号通路，“基因-代谢物”调控网络显示非经典Smad信号途径中的基因参与到了能量代谢的调节。并且牛蒡子调控Fibronectin、Vimentim、Snail、E-cadherin、N-cadherin等上皮-间质转化（EMT）进程的标志蛋白（P<0.05），抑制MAPK信号通路激活。结论: 牛蒡子通过调控能量代谢抑制EMT治疗纤维化，并且涉及调控MAPK等非经典Smad信号通路，为牛蒡子治疗PPF的临床应用及后续研究提供理论支持。.
Keywords: Arctium lappa; MAPK; metabolomics; network pharmacology; post-viral pneumonia pulmonary fibrosis.