Network Pharmacology-Serum Metabolomics Integration Identifies Key Targets, Biomarkers and Mechanism of Sendeng-4 in Rheumatoid Arthritis Therapy.

Rheumatoid arthritis (RA) is characterized by chronic inflammatory synovitis and immunometabolic dysregulation, necessitating safer multi-target therapies. Sendeng-4 (SD-4) is a traditional Mongolian medicinal formula composed of four botanical ingredients (Xanthoceras sorbifolia Bunge, Gardenia jasminoides Ellis, Chebulae Fructus, and Toosendan Fructus) traditionally used for RA. However, its circulating material basis and mechanisms remain unclear. This study aimed to elucidate the pharmacodynamic constituents and potential mechanisms of SD-4 in RA. An integrative approach combining serum pharmacochemistry, network pharmacology, molecular docking, in vivo pharmacodynamics, and non-targeted serum metabolomics was employed. Absorbable constituents of SD-4 were identified by HPLC-Q-Exactive-Orbitrap-MS. Key targets and pathways were explored using network analysis, and therapeutic efficacy and metabolomic biomarkers were evaluated in a collagen-induced arthritis mouse model. Twenty absorbable constituents were detected, with SRC, PIK3CA, and PIK3R1 emerging as key targets involved in PI3K-AKT and HIF-1 signaling. SD-4 treatment significantly reduced arthritis scores (by up to 45% in high-dose mice), paw thickness, and serum pro-inflammatory cytokines (TNF-α, IL-6, IL-1β decreased by 30-55%, all P < 0.05). Serum metabolomics identified 46 disease-associated metabolites reversed by SD-4, particularly involving tryptophan metabolism and glycolysis/gluconeogenesis. Correlation analyses suggest these metabolic changes are associated with modulation of inflammatory pathways. SD-4 alleviates arthritis in mice, likely through modulation of the PI3K/SRC network and partial rebalancing of glycolysis-tryptophan metabolic crosstalk, restoring immunometabolic homeostasis. These findings support the potential clinical application of SD-4 for RA and provide a mechanistic framework for its multi-target actions.