Bergenin (BG) is a naturally occurring C-glycoside with demonstrated anti-arthritic potential. Its therapeutic efficacy is compromised due to its lower absorption and instability at neutral-basic pH. The present study reports fabrication of gum xanthan (GX) stabilized silver nanoparticles (AgNPs) with BG for anti-arthritic activity in a CFA-induced arthritis model targeting ROS, cytokines and TLR expression. NPs were characterized through UV-vis, zetasizer, FT-IR and AFM. Oral administration of BG loaded NPs (1 mg kg⁻¹) exhibited potent anti-arthritic activity with a minimal arthritic score, mild to moderate paw tissue swelling, reduced degenerative changes along with mild articular changes and less influx of inflammatory cells in macroscopic X-ray and histological examination. Administration of BG and its NPs suppressed the levels of reactive oxygen species (ROS) significantly as compared to the arthritic control group. Moreover, increased production of O₂˙⁻ in human neutrophils, stimulated by opsonized zymosan (OZ) and phorbol-12-myristate-13-acetate (PMA) was also suppressed. BG and its loaded NPs were revealed to antagonize the oxidative stress via interference with the NADPH oxidase metabolic pathway. Their anti-oxidant activity was further assessed by their inhibitory effect against TLR (TRL-2 & -4) and cytokine (IL-1β, IL-6 and TNF-α) production. The current investigation validates GX stabilized AgNPs as stable and promising multi-targeted therapeutic nano-cargo for BG delivery with efficient treatment of RA.

Rheumatoid arthritis (RA) is a chronic autoimmune disease of synovial inflammation and joint destruction. This study reports anti-arthritic potential of opuntioside-I opuntiol, and its gold and silver nanoparticles (NPs) against Complete Freund's Adjuvant (CFA)-induced arthritic rats. The mechanistic studies were performed targeting TLRs (TLR-2 and TLR-4) and cytokines (IL-1β and TNF-α) expressions to validate their anti-inflammatory and immuno-modulatory response. The nano-formulations were successfully characterized employing Atomic Force Microscopy (AFM) and Dynamic Light Scattering (DLS) analysis. Opuntiol and opuntioside (OP and OPG: 10, 50 and 100 mg/kg) and opuntiol-coated silver and gold NPs (OP-AgNPs and OP-AuNPs: 0.5, 1 and 3 mg/kg) treatments in arthritic rat have shown minimal arthritic score exhibiting mild to moderate articular changes and tissue swelling in ankle joints. Radiographic examination reveals significant reduction in synovitis with improvement in joints degenarative changes in the presence of aforementioned treatments. Likewise, histology of rat ankle joints depicted comparatively lesser influx of inflammatory cells and diminished granulamatous inflammation. Moreover, treatment groups suppressed protein and mRNA expressions of TLRs (TLR-2 and TLR-4) and cytokines (IL-1β and TNF-α) levels were also significantly declined in the presence of OPG, OP and its NPs comparing to arthritic control. This investigation concludes, the tested compounds and nano-formulations successfully restored the disease progression in CFA-induced arthritic rat owing to their immunomodulatory and anti-inflammatory potentials and can be considered for RA targeted therapy to address the utmost challenges of the disease.