Gentiopicroside attenuates lupus arthritis by targeting galectin-mediated macrophage activation.

Abstract

BACKGROUND: Inflammatory arthritis represents a common and clinically challenging manifestation of systemic lupus erythematosus (SLE), with current therapeutic options often exhibiting limited efficacy. PURPOSE: This study aimed to investigate the anti-arthritic effects and underlying mechanism of gentiopicroside (GPS), a key bioactive constituent of the Jiawei Baihu Jia Guizhi Decoction (JBH), with a specific focus on its interaction with galectin-9-mediated pathways in macrophage activation. STUDY DESIGN: The anti-arthritic efficacy of GPS was investigated using a pristane-induced arthritis (PIA) mouse model, which recapitulates key features of SLE-associated arthritis. Integrated transcriptomic and network pharmacology approaches were employed for mechanistic exploration, followed by experimental validation in vitro and in vivo. METHODS: The PIA mouse model was treated with GPS to evaluate its effects on joint inflammation, synovial pathology, and bone remodeling. Transcriptomic profiling of joint tissues and network pharmacology analysis were conducted to identify potential targets. The interaction between GPS and Galectin-9 (Gal-9) was characterized using molecular docking and biophysical assays (determining a Kd of ∼350 nM). The functional impact of GPS on Gal-9-dependent NF-κB signaling, pro-inflammatory cytokine secretion, and macrophage activation was assessed in cellular models and PIA mice. RESULTS: GPS treatment significantly alleviated joint inflammation, synovial hyperplasia, and bone erosion in PIA mice, while also restoring the balance of bone remodeling. Integrative analyses pinpointed Gal-9 as a critical target, and GPS was confirmed to bind Gal-9 with high affinity. Functionally, GPS inhibited Gal-9-triggered NF-κB activation, suppressed the production of pro-inflammatory cytokines, and reduced macrophage infiltration and activation. Furthermore, GPS ameliorated systemic inflammation, lowered autoantibody levels, and improved joint integrity in PIA mice, demonstrating efficacy comparable to methotrexate. CONCLUSION: Gentiopicroside, a key active constituent of the JBH, attenuates lupus arthritis by specifically targeting Galectin-9 and subsequently disrupting galectin-driven macrophage activation. These findings highlight GPS as a promising targeted therapeutic candidate for the management of SLE-related joint damage.