Systematic Analysis of the Mechanism of Polygoni Multiflori Caulis in Improving Depressive Disorder in Mice via Network Pharmacology Combined with Ultra-High Performance Liquid Chromatography Coupled with Quadrupole Exactive Orbitrap Mass Spectrometer

Background and Objective: Depressive disorder (DD) is a common chronic and highly disabling disease. Polygoni Multiflori Caulis (PMC), a traditional Chinese medicine, has been listed in the 2020 edition of the Chinese Pharmacopoeia. Here, the antidepressant effects and mechanisms of PMC were explored for the first time. Methods: We observed the safety of PMC at a 10-fold clinically equivalent dose. Depressed mice were induced by chronic unpredictable mild stress (CUMS) and were used to evaluate the antidepressant effects of PMC via the sucrose preference test and the tail suspension test. The composition of PMC was identified by ultra-high performance liquid chromatography coupled with quadrupole exactive orbitrap mass spectrometer, and the active components, important targets, and potential mechanism of PMC in DD treatment were predicted via network pharmacology. Investigation included active compounds and DD-related targets screening, Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation, PMC-compound-target-pathway- DD network construction, and Molecular docking. Results: In the safety evaluation of PMC, no toxic side effects or deaths occurred. There were no significant differences in liver function (ALT, AST, and TP; P > 0.05) and kidney function (BUN, CRE, and UA; P > 0.05) in each group of mice. Compared to the control group, the model group of mice showed significantly decreased sucrose preference and significantly increased immobility time (P < 0.01 or P < 0.05). Compared with the model group, the mice in the PMC low, medium, and high dose groups showed a significant decrease in immobility time and a significant increase in sucrose preference. In the PMC-Compound-Target-Pathway-DD network, 54 active compounds, 83 common targets, and 13 major signaling pathways were identified for the treatment of DD. Molecular docking verified that the active compounds could effectively bind with the hub targets. Conclusion: PMC is a relatively safe antidepressant herbal medicine with its potential mechanism involving multiple compounds, targets, and pathways.