Exploring the Therapeutic Mechanism of Xiehuo Pingtu San in Treating Thyroid Eye Disease Based on Network Pharmacology, Molecular Docking, and Molecular Dynamics Simulation.

Xiehuo Pingtu San (XHPTS) has been shown to be safe and effective in treating thyroid eye disease (TED), yet its underlying mechanisms remain unclear. This study aimed to elucidate the active ingredients of XHPTS and their therapeutic mechanisms in TED through network pharmacology, molecular docking, and molecular dynamics simulations. Active ingredient targets for XHPTS were screened through the TCMSP and BATMAN-TCM databases. TED-related targets were obtained from GeneCards, OMIM, and CTD, and differentially expressed genes (DEGs) between TED patients and healthy controls were retrieved from GEO. The intersecting targets among active ingredient targets, disease targets, and DEGs were defined as key targets. Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to identify biological processes and pathways associated with XHPTS intervention in TED. Key targets were further mapped to organs to predict potential "target-organ" interactions. A protein-protein interaction (PPI) network was used to identify hub genes. Immune microenvironment analysis was conducted to compare immune cell infiltration between TED and control samples and to assess correlations between differential immune cells and hub genes. A ceRNA network ("mRNA-miRNA-lncRNA") was constructed based on hub genes. Molecular docking and molecular dynamics simulations were applied to evaluate the binding affinities between key active ingredients and hub genes. We found that XHPTS may exert therapeutic effects on TED through biological functions, such as reactive oxygen species (ROS) responses and fatty acid (FA) metabolism, as well as signaling pathways, such as IL-17. Several shared targets, such as ADIPOQ, CES1, and CAT, were identified across these pathways. Organ localization analysis indicated that the liver plays a crucial role in the therapeutic action of XHPTS against TED. Immune microenvironment analysis revealed significant differences in immune cell infiltration between TED patients and healthy individuals, particularly in plasma cells, and these differential immune cells were correlated with the identified hub genes. A ceRNA regulatory network revealed that 153 lncRNAs may regulate 8 miRNAs and 4 hub genes. Molecular docking and molecular dynamics simulations showed strong binding affinities between key active ingredients (quercetin, luteolin, and paeoniflorin) and hub genes (IL-6, PPARγ, CXCL8, CAT, and CAV1). The binding free energies of key complexes ranged from -51.923 to -98.221 kJ/mol, confirming stable interactions. XHPTS exerts therapeutic effects on TED through multicomponent, multitarget, and multipathway approaches.