Exploration the mechanism of Shenling Baizhu San in the treatment of chronic obstructive pulmonary disease based on UPLC-Q-TOF-MS/MS, network pharmacology and in vitro experimental verification

Shenling Baizhu San (SLBZS) is a formula of traditional Chinese medicine (TCM) that enhances the functions of the qi, spleen, and lung. According to the theory of TCM, chronic obstructive pulmonary disease (COPD) is often caused by lung qi deficiency, and SLBZS is often used in the treatment of COPD and has achieved remarkable results. However, the active components of SLBZS absorbed in serum and the underlying mechanism of SLBZS in treating COPD remain unclear and require further studies. The objective of this study is to investigate the active components of SLBZS in rat serum, as well as the crucial targets and signaling pathways involved in the therapeutic effects of SLBZS for COPD. First, the absorption components and metabolites of SLBZS in rat serum were identified using ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS). Second, potential targets of SLBZS for the treatment of COPD were acquired from publicly accessible online sources. Cytoscape (v3.7.0) software was used to construct a component-target-pathway network and a protein-protein interaction (PPI) network. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of potential targets was performed using the Metascape database. The binding status of the active components in SLBZS to the potential targets was assessed with molecular docking technology. Finally, a cell model of COPD was successfully developed for experimental validation In vitro. A total of 108 active components were identified, including 30 prototype components and 78 metabolites. A total of 292 potential targets for the treatment of COPD were identified, including TNF, IL-6, TLR9, RELA, and others. The KEGG pathway included inflammatory mediator regulation of TRP channels, necroptosis, and the NF-κB signaling pathway, among others. The In vitro experiments showed that SLBZS-containing serum had the ability to decrease the levels of inflammatory factors and cell death. Additionally, it was observed that SLBZS-containing serum could control the expression levels of TLR9, MyD88, TRAF6, NF-κB, and IκBα at the mRNA and protein levels. These findings suggested that SLBZS-containing serum was likely to be involved in the regulation of the TLR9/NF-κB pathway. The mechanism of action of SLBZS on COPD was preliminarily elucidated using UPLC-Q-TOF-MS/MS, network pharmacology, and In vitro experiments. The primary active components and potential targets of SLBZS were identified, providing a scientific foundation for further research.