[Jiawei Xiaoyao Pills improves depression-like behavior in rats by regulating neurotransmitters, inhibiting inflammation and oxidation and modulating intestinal flora].

Abstract

Objectives: To explore the bioactive components in Jiawei Xiaoyao Pills (JWXYP) and their mechanisms for alleviating depression-like behaviors.

Methods: The active compounds, key targets, and pathways of JWXYP were identified using TCMSP and TCMIP databases. Thirty-six SD rats were randomized equally into 6 groups including a control group and 5 chronic unpredictable mild stress (CUMS)-induced depression groups. After modeling, the 5 model groups were treated with daily gavage of normal saline, 1.8 mg/kg fluoxetine hydrochloride (positive control drug), or JWXYP at 1.44, 2.88, and 4.32 g/kg. The depression-like behaviors of the rats were evaluated using behavioral tests, and pathological changes in the liver and hippocampus were examined with HE staining. The biochemical indicators in the serum and brain tissues were detected using ELISA. Serum metabolomics analysis was performed to identify the differential metabolites using OPLS-DA, and gut microbiota changes were analyzed using 16S rDNA sequencing.

Results: Network pharmacology revealed that menthone and paeonol in JWXYP were capable of penetrating the blood-brain barrier to regulate inflammatory pathways and protect the nervous system. In the rat models subjected to CUMS, treatment with JWXYP significantly improved body weight loss, sucrose preference and open field activities, reduced liver inflammation, alleviated structural changes in the hippocampal neurons, decreased serum levels of TNF‑α, IL-1β, IL-6 and LBP, and increased 5-HT and VIP concentrations in the serum and brain tissue, and these effects were the most pronounced in the high-dose group. Metabolomics analysis showed changes in such metabolites as indole-3-acetamide and acetyl-L-carnitine in JWXYP-treated rats, involving the pathways for bile acid biosynthesis and amino acid metabolism. 16S rDNA analysis demonstrated increased gut microbiota diversity and increased abundance of Lactobacillus species in JWXYP-treated rats.

Conclusions: JWXYP alleviates depression-like symptoms in rats by regulating the neurotransmitters, inhibiting inflammation and oxidation, and modulating gut microbiota.