Integration of network pharmacology and experimental verification to reveal the active components and molecular mechanism of modified Danzhi Xiaoyao San in the treatment of depression

Ethnopharmacological relevance: Modified Danzhi Xiaoyao San (MDXS) is an effective clinical prescription for depression in China, which was deprived of Danzhi Xiaoyao San in the Ming Dynasty. MDSX has significant implications for the development of new antidepressants, but its pharmacological mechanism has been rarely studied. Aim of the study: To reveal the active components and molecular mechanism of MDXS in treating depression through network pharmacology and experimental verification in vivo and in vitro. Materials and methods: UPLC-Q-TOF-MS/MS was used to identify the chemical components in the MDXS freezedried powder, drug-containing serum, and cerebrospinal fluid (CSF). Based on the analysis of prototype components in the CSF, the major constituents, potential therapeutic targets and possible pharmacological mechanisms of MDXS in treating depression were investigated using network pharmacological and molecular docking. Then corticosterone (CORT)-induced mice model of depression was established to investigate the antidepressant effects of MDXS. HT22 cells were cultured to verify the neuroprotective effects and core targets of the active components. Results: There were 81 compounds in MDXS freeze-dried powder, 36 prototype components in serum, and 13 prototype components in CSF were identified, respectively. Network pharmacology analysis showed that these 13 prototype components in the CSF shared 190 common targets with depression, which were mainly enriched in MAPK and PI3K/AKT signaling pathways. PPI analysis suggested that AKT1 and MAPK1 (ERK1/2) were the core targets. Molecular docking revealed that azelaic acid (AA), senkyunolide A (SA), atractylenolide III (ATIII), and tokinolide B (TB) had the highest binding energy with AKT1 and MAPK1. Animal experiments verified that MDXS could reverse CORT-induced depression-like behaviors, improve synaptic plasticity, alleviate neuronal injury in hippocampal CA3 regions, and up-regulate the protein expression of p-ERK1/2 and p-AKT. In HT22 cells, azelaic acid, senkyunolide A, and atractylenolide III significantly protected the cell injury caused by CORT, and up-regulated the protein levels of p-ERK1/2 and p-AKT. Conclusions: These results suggested that MDXS may exert antidepressant effects partially through azelaic acid, senkyunolide A, and atractylenolide III targeting ERK1/2 and AKT.