This study investigated the effect and mechanism of chrysosplenol D (CD) on LPS-induced acute lung injury in mice. Histological changes in the lungs were measured by hematoxylin-eosin staining. The levels of IL-6, IL-1β, and TNF-α in the bronchoalveolar lavage fluid were detected by ELISA. The levels of oxidative stress were detected by the cuvette assay. Immune cells in peripheral blood, the levels of reactive oxygen species, and apoptosis of primary lung cells were detected by flow cytometry. The mRNA levels of TLR4, MyD88, IL-1β, and NLRP3 were measured by quantitative real-time polymerase chain reaction. The levels of proteins in apoptosis and the TLR4-MAPKs/NF-κB signaling pathways were detected by Western blot. Hematoxylin-eosin staining showed that CD could improve lung injury; decrease the levels of inflammatory factors, oxidative stress, reactive oxygen species, and cell apoptosis; and regulate the immune system. Moreover, CD could down-regulate the mRNA levels of TLR4, MyD88, NLRP3, and IL-1β in lung, and the protein levels of Keap-1, Cleaved-Caspase-3/Caspase-3, Cleaved-Caspase-9/Caspase-9, TLR4, MyD88, p-ERK/ERK, p-JNK/JNK, p-p38/p38, p-p65/p65, NLRP3, and IL-1β, and up-regulated the levels of Bcl-2/Bax, p-Nrf2/Nrf2, and HO-1. The results suggested that CD could protect mice against LPS-induced acute lung injury by inhibiting oxidative stress, inflammation, and apoptosis via the TLR4-MAPKs/NF-κB signaling pathways.

本研究探讨了金脾醇 D (CD) 对 LPS 诱导的小鼠急性肺损伤的作用和机制。通过苏木精-伊红染色测量肺部的组织学变化。采用ELISA法检测支气管肺泡灌洗液中IL-6、IL-1β、TNF-α的水平。通过比色皿测定法检测氧化应激水平。流式细胞仪检测外周血免疫细胞、活性氧水平及原代肺细胞凋亡情况。通过实时定量聚合酶链式反应测定 TLR4、MyD88、IL-1β 和 NLRP3 的 mRNA 水平。Western blot检测细胞凋亡及TLR4-MAPKs/NF-κB信号通路蛋白水平。苏木精-伊红染色显示CD可以改善肺损伤；降低炎症因子、氧化应激、活性氧和细胞凋亡的水平；并调节免疫系统。此外，CD可下调肺中TLR4、MyD88、NLRP3和IL-1β的mRNA水平，以及Keap-1、Cleaved-Caspase-3/Caspase-3、Cleaved-Caspase-9/Caspase的蛋白水平-9、TLR4、MyD88、p-ERK/ERK、p-JNK/JNK、p-p38/p38、p-p65/p65、NLRP3 和 IL-1β，并上调 Bcl-2/Bax 水平、p-Nrf2/Nrf2 和 HO-1。结果表明，CD 可以通过 TLR4-MAPKs/NF-κB 信号通路抑制氧化应激、炎症和细胞凋亡，从而保护小鼠免受 LPS 诱导的急性肺损伤。