Unraveling mechanisms of Erchen decoction in treatment of atherosclerosis: A comprehensive study integrating network pharmacology, molecular docking, molecular dynamics simulation, and experimental validation

Objective Erchen decoction (ECD) is documented in “ Formulary of the Bureau of Taiping People’s Welfare Pharmacy ” as having therapeutic effects on lipid disorders through multiple targets and pathways. However, the underlying mechanisms of ECD in atherosclerosis (AS) treatment remain to be elucidated. Methods UPLC-Q-E-Orbitrap-MS was used to identify the active ingredients of ECD and the ECD-containing serum (ECDS). Active ingredients identified from the ECDS were used in network pharmacology to predict potential therapeutic targets of ECD in AS, followed by molecular docking and molecular dynamics simulation to evaluate their binding affinities with adenosine monophosphate-activated protein kinase (AMPK), peroxisome proliferator-activated receptor gamma (PPAR γ ), liver X receptor alpha (LXR α ), and ATP-binding cassette transporters A1 and G1(ABCA1/G1) proteins. In vivo , the efficacy of ECD against AS was assessed via blood lipid analysis, inflammatory biomarker analysis, and histopathological staining of the aorta. In vitro , a foam cell model was established using mouse primary peritoneal macrophages, and Oil Red O staining, Western blotting, and cholesterol efflux assays were performed to investigate the effects of ECD on cholesterol metabolism. Pharmacological inhibitor experiments were used to elucidate regulatory effects of ECD on the AMPK-mediated PPAR γ /LXR α /ABCA1/G1 signaling pathway. Results A total of 37 active ingredients were identified in the ECDS. Network pharmacology analysis indicated that ECD primarily regulated inflammation-related pathways and modulated cholesterol metabolism through the AMPK and PPAR signaling pathways, targeting key lipid metabolism targets, such as PPARA and PPARG. Molecular docking revealed favorable binding affinities between multiple ECDS ingredients and the AMPK, PPAR γ , LXR α , and ABCA1/G1 proteins, with the five strongest protein-ligand pairs being AMPK-liquiritin apioside, PPARγ-narirutin, LXR α -apioglycyrrhizin, ABCA1-apigenin-7- O -glucoside, and ABCG1-hesperidin. Molecular dynamics simulation further validated the docking results. In vivo , ECD attenuated AS progression, as evidenced by decreased lipid levels, reduced expression of inflammatory cytokines (tumor necrosis factor-alpha (TNF- α ), interleukin-6 (IL-6), and -IL-1 β , diminished relative en face aortic lesion area, plaque area, lipid accumulation, macrophage infiltration, and increased collagen content in plaques. In vitro , the ECDS reduced the formation of macrophage-derived foam cells by promoting cholesterol efflux. In terms of the specific mechanism, both in vivo and in vitro pharmacological inhibitor experiments confirmed that the therapeutic effects of ECD on AS were mediated via the AMPK-mediated PPAR γ /LXR α /ABCA1/G1 signaling pathway. Conclusion This research indicated that ECD effectively attenuated AS progression by targeting the AMPK-mediated PPAR γ /LXR α /ABCA1/G1 signaling pathway, providing new insights into the anti-AS mechanisms of ECD.