Jinwu Jiangu Capsule Alleviates Rheumatoid Arthritis Symptoms by Regulating the ADCY10 and cAMP/RANKL Pathways

Ethnopharmacological relevance: Rheumatoid arthritis (RA) is a systemic autoimmune disease that primarily affects joints and damages other tissues, including the heart, kidneys, lungs, digestive system, eyes, skin and nervous system. Jinwu Jiangu Capsule (JWJG) is effective in tonifying kidneys, activating blood circulation, and dispelling wind and dampness. Meanwhile, it produces favorable clinical results in relieving joint pain and reducing inflammation. However, precise therapeutic effect and mechanisms of JWJG on RA remain unclear.

Aim of the study: The traditional Chinese medicine JWJG exhibits certain properties in anti-inflammation and pain relief for RA treatment. This study aimed to investigate the efficacy of JWJG and elucidate its underlying mechanisms in RA treatment.

Materials and methods: A collagen-induced arthritis (CIA) rat model was administered JWJG orally at varying doses for 28 days, alongside control and positive control groups treated with saline and leflunomide, respectively. Indicators including joint swelling, bone loss, histopathological changes, Th17/Treg lymphocyte differentiation, and inflammatory factor expression were assessed. RNA sequencing of synovial tissues identified JWJG-influenced genes and pathways. RASFs treated with ADCY10 lentivirus, PKA agonist, or AR plasmid underwent additional JWJG-containing serum or β-sitosterol treatment to monitor ADCY10, RANKL, and cAMP pathway alterations.

Results: JWJG administration significantly reduced joint swelling, bone loss, and inflammation, balanced Th17/Treg, and suppressed TNF-α, IL-1β, IL-6, and RANKL levels. In RASFs, JWJG downregulated ADCY10, cAMP, and phospho-PKA/CREB, thereby inhibiting osteoclast differentiation. Meanwhile, β-sitosterol decreased AR levels, which suppressed ADCY10 and RANKL expression. JWJG treatment could directly/indirectly inhibit ADCY10 reduced cAMP/RANKL, inflammation, and osteoclastogenesis, enhancing RA symptomatology comparable to leflunomide. It demonstrated superior regulation of Th17/Treg ratios and cytokine suppression, with potential to substantially improve RA patients' quality of life.

Conclusions: JWJG inhibited ADCY10, decreased cAMP/RANKL, and impeded inflammation and osteoclastogenesis, with a notable improvement in RA symptoms comparable to leflunomide. It can be introduced as a potential new therapeutic strategy for preventing or even reversing bone damage and improving the quality of life for RA patients.