Integrative multi-omics reveals that Salvia miltiorrhiza active fraction ameliorates rheumatoid arthritis in rats via inhibiting inflammation and ferroptosis.

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, highly disabling autoimmune disease requiring lifelong management, yet current therapies carry substantial long-term toxicity and high costs. Salvia miltiorrhiza is used clinically in the treatment of RA due to its pharmacological properties such as promoting blood circulation, removing blood stasis, and anti-inflammatory effects. However, the specific active fraction of Salvia miltiorrhiza responsible for its therapeutic effect on RA and the underlying mechanism remains unclear.

OBJECTIVE

To explore active fraction from Salvia miltiorrhiza for the treatment of RA and elucidate their underlying mechanisms.

METHODS

The active fraction of Salvia miltiorrhiza was screened via in vitro anti-inflammatory assay and in vivo pharmacokinetic evaluation. The composition was analyzed using UHPLC-Q Exactive-MS/MS and HPLC. An in vivo model of RA was established in rats using the collagen-induced arthritis (CIA) method. Therapeutic effects were assessed by RT-qPCR, Western Blot, and ELISA. Mechanisms were predicted via multi-omics analysis and validated using Western Blot, immunofluorescence, RT-qPCR, and fluorescent probes.

RESULTS

One ethyl acetate extract (named ET) was identified as the active fraction from Salvia miltiorrhiza. In RA rats, ET treatment significantly delayed disease progression and alleviated pathological manifestations. Multi-omics analysis revealed ET modulated amino acid pathways, and impacted macrophage metabolic, inflammation and ferroptosis pathways. Western Blot, immunofluorescence, and RT-qPCR showed that ET not only directly inhibited macrophage inflammatory responses but also indirectly suppressed the activation of fibroblast-like synoviocytes by regulating macrophages. At the same time, ET effectively blocks the ferroptosis process by simultaneously regulating lipid peroxidation and antioxidant signaling. Furthermore, ET's five principal compounds, salvianolic acid B (SalB), dihydrotanshinone I (DIH), cryptotanshinone (CTS), tanshinone I (TanI), and tanshinone IIA (TanIIA), demonstrated inhibitory effects on both inflammation and ferroptosis.

CONCLUSION

The Salvia miltiorrhiza active fraction ET ameliorates RA pathology by simultaneously regulating inflammation, ferroptosis, amino acid metabolism and synoviocyte dysregulation, demonstrating significant therapeutic potential for RA treatment.