清肺理痰方通过调节肠道菌群与SCFAs代谢改善急性肺损伤小鼠的作用机制研究

Study on the Mechanism of Qingfei Litan Formula in Improving Acute Lung Injury in Mice by Regulating Gut Microbiota and SCFAs Metabolism

关键词:  急性肺损伤  清肺理痰方  肠道菌群  短链脂肪酸  氧化应激  炎症反应

Key words:  Acute Lung Injury  Qingfei Litan Decoction  Gut Microbiota  Short-Chain Fatty Acids  Oxidative Stress  Inflammatory Response

摘要:

目的 分析急性肺损伤小鼠的肠道菌群特点及清肺理痰方的干预效果，探讨肠道菌群变化与肺部炎症、氧化应激、短链脂肪酸（short-chain fatty acids, SCFAs）代谢之间的相关性，以揭示清肺理痰方的作用机制。方法 不同剂量清肺理痰方预防给药后进行LPS气管滴注建立ALI小鼠模型，24小时后安乐死并检测小鼠BALF中炎性细胞数目和炎症因子水平，观察肺组织病理变化，计算肺系数及肺湿/干比，检测肺组织氧化应激指标的表达水平、血清中SCFAs的含量，进行肠道菌群16S rRNA高通量测序并分析。结果 清肺理痰方干预能减轻急性肺损伤小鼠的肺泡损伤及肺水肿，降低BALF中炎性细胞数目、炎症因子水平，减少肺组织中的MDA含量、提高SOD和GPx活性，提高血液中SCFAs的含量。肠道菌群分析结果显示，清肺理痰方能提升肠道菌群的Alpha多样性，增加有益菌Lachnospiraceae NK4A136、Lactobacillus、Prevotellaceae UCG-001、Prevotellaceae NK3B31、Ruminiclostridium 6、Enterorhabdus、Ruminococcaceae UCG-013，减少有害菌Alloprevotella、Erysipelatoclostridium、Peptococcus属水平上的相对丰度。相关性分析显示，7个有益菌属的相对丰度肺部炎症和氧化应激水平均呈负相关，与血液中乙酸、丙酸、丁酸含量均呈正相关，其中仅3个有益菌与戊酸含量呈正相关；有害菌属的相关性则相反。此外，乙酸、丙酸、丁酸与BALF中炎症因子及氧化应激水平均呈负相关，戊酸仅与BALF中炎症因子（IL6、TL-1β）水平呈负相关。结论 清肺理痰方可能通过调节肠道菌群结构及SCFAs代谢，发挥抗炎和抗氧化应激的作用，保护ALI小鼠肺组织。

Abstract:

OBJECTIVE To analyze the characteristics of gut microbiota in mice with acute lung injury and the intervention effect of Qingfei Litan Formula. This study aims to explore the correlation between changes in gut microbiota and lung inflammation, oxidative stress, and short-chain fatty acids (SCFAs) metabolism, thereby revealing the mechanism of action of Qingfei Litan Formula. METHODS The ALI mouse model was established via LPS tracheal instillation after administering different doses of Qinglong Lipophlegm Formula. After euthanasia, we evaluated inflammatory cells and factors in BALF, examined lung pathology, calculated the lung coefficient and wet/dry ratio, assessed oxidative stress markers in lung tissues, measured SCFAs levels in serum, and conducted 16S rRNA sequencing of the intestinal microbiota. RESULT Qingfei Litan Decoction alleviated alveolar damage and pulmonary edema in ALI mice, reduced inflammatory cells and factors in BALF, decreased MDA in lung tissue, increased SOD and GPx activities, and elevated SCFAs in blood. It enhanced gut microbiota diversity, increased beneficial bacteria like Lachnospiraceae NK4A136 and Lactobacillus, and decreased harmful bacteria like Alloprevotella. Beneficial genera were negatively correlated with pulmonary inflammation and oxidative stress, and positively with acetic, propionic, and butyric acids in blood. Harmful genera showed opposite correlations. Acetic, propionic, and butyric acids were negatively correlated with inflammatory factors and oxidative stress in BALF, while pentanoic acid was negatively correlated with IL6 and TNF-α levels. CONCLUSION Qingfei Litan Formula may exert anti-inflammatory and anti-oxidative stress effects by regulating gut microbiota and SCFAs metabolism, thereby protecting lung tissue in ALI mice.