Study on the discovery of lung-descending herbs and bioactive constituents using TRP channel-functionalized screening.

The objectiveof the study is to investigate the potential association between transient receptor potential (TRP) channels and lung-descending traditional Chinese medicine (LDTCMs). To investigate the potential association between TRP channels and traditional Chinese herbs with lung-descending or lung-diffusing properties, we systematically screened the bioactive components and predicted targets of five lung-descending herbs (Cynanchi Stauntonii Rhizoma Radix, Trichosanthis Fructus, Armeniacae Semen Amarum, Raphani Semen, and Lepidii Semen, also known as Descurainiae Semen) and five lung-diffusing herbs (Ephedrae Herba, Angelicae Dahuricae Radix, Platycodonis Radix, Mori Folium, and Perillae Folium). Target prediction was performed using the TCMSP platform and SwissTargetPrediction databases, followed by Venn analysis to identify herb-specific targets. These targets were subsequently applied to construct a protein-protein interaction (PPI) network with topological visualization. Functional enrichment analyses were then conducted based on Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. To validate the link between lung-descending herbs and specific TRP channel subtypes, calcium flux assays were employed to assess the agonistic effects of ten selected herbs on TRP channels. Finally, molecular docking was performed to identify the key active compounds from lung-descending herbs with the capacity to activate the TRPM8 channel. Network pharmacology analysis revealed that traditional Chinese herbs, particularly those with lung-descending properties, significantly modulate the TRP channel-mediated inflammatory pathways, including TRPM8 and TRPA1. Calcium flux assays demonstrated that extracts from Raphani Semen (RS) and Descurainiae Semen Lepidii Semen (DSLS) can directly activate TRPM8 channels, consistent with previous reports showing that various herbal components and immunosuppressive agents can modulate TRPM8 activity. In contrast, TRPA1 channels were not directly activated by extracts of lung-descending herbs and were therefore excluded from subsequent analyses. Molecular docking simulations further indicated that specific chemical constituents within RS and DSLS form stable binding configurations with key residues lining the TRPM8 pore, suggesting stronger ligand-receptor interactions. Collectively, these results indicate that specific constituents within RS and DSLS contribute to their effects through direct activation of TRPM8 channels. This study employs an integrated approach combining network pharmacology, functional calcium flux assays, and molecular docking to establish TRP channels as effective functional filters for the systematic screening of lung-descending herbs. This strategy not only identifies key herbal candidates with TRP affinity and their bioactive constituents but also provides evidentiary support for developing TRP-targeted pulmonary therapeutics. From the perspective of traditional Chinese medicine, these findings elucidate the mechanistic basis of lung-descending efficacy. From the standpoint of modern pharmacology, they reveal specific TRP channel interactions unique to lung-descending herbs, thereby establishing a molecular foundation for the development of novel respiratory therapeutics.