Darutoside ameliorates adjuvant-induced arthritis in mice by repolarizing M1/M2 macrophages through inhibition of JAK2-STAT3-p65 signaling pathway

Abstract

Darutoside (DA), a diterpenoid compound derived from Herba Siegesbeckiae , possesses notable anti-inflammatory properties. This study evaluated the effectiveness of DA in treating rheumatoid arthritis (RA) symptoms and elucidated the relevant mechanisms. The anti-RA efficacy of DA was investigated in a Complete Freund’s Adjuvant (CFA)-induced arthritis mouse model, while RAW264.7 macrophages were used to examine DA’s impact on macrophage polarization in vitro . Targets of DA for RA were predicted through protein-protein interaction networks and pathway enrichment analysis. Subsequently, mechanisms were verified through in vitro assays. The results showed that DA alleviated the symptoms in the CFA mouse model, as evidenced by reduced clinical scores, attenuated paw swelling, and decreased inflammatory response. Moreover, DA induced repolarization of M1/M2 macrophages in both the CFA model mice and RAW264.7 cells. Network pharmacology analysis suggested that DA may exert its anti-RA effects by modulating the JAK-STAT signaling pathway. Western blotting confirmed that DA inhibited the JAK2-STAT3-p65 pathway, thereby suppressing M1 macrophage polarization. Furthermore, the repolarization effect of DA on macrophages was counteracted in JAK2-silenced cells. These findings indicate that DA attenuates arthritis symptoms in CFA mice, and this effect may be attributed to its regulation of macrophage M1/M2 polarization through suppression of the JAK2-STAT3 pathway and downstream p65 activation.