Exploring molecular mechanism of Panlongqi Tablet (PLQT) against RA: Integrated network pharmacology, molecular docking and experiment validation

Background and purpose: Panlongqi Tablet (PLQT), a proprietary Chinese medicine composed of 29 herbs, has been included in the Chinese Medical Insurance List and has shown promising therapeutic effects on patients with rheumatoid arthritis (RA) in clinical practice. However, the molecular mechanisms of PLQT against RA have not been fully elucidated. This study aimed to further decipher the active ingredients and molecular mechanism of PLQT anti-RA. Methods: A Complete Freund's adjuvant (CFA)-induced rat model was established to evaluate the pharmacodynamic effects of PLQT against RA, the assessment included arthritis index, paw thickness, ankle diameter, morphological and histopathological analysis. Network analysis was used to elucidate the active ingredients and underlying mechanisms of PLQT in the treatment of RA, molecular docking was conducted to assess the binding of active ingredients to key targets. In vitro and in vivo experimental verification were employed to reveal the mechanism of PLQT against RA. Results: Experimentally, PLQT improved CFA-induced arthritis without evident side effects. Network analysis revealed that the active ingredients in PLQT were mainly flavonoids, biscoumarin derivatives, alklaloid and lignans. Integrated with molecular docking studies, the molecular mechanisms of PLQT against RA were enriched in inflammatory response, immune regulation, angiogenesis, osteoclast differentiation and autophagy. In vitro experiments confirmed that PLQT exerted anti-inflammatory and immune regulatory effects by targeting the inflammatory response of M1 macrophages and the biological functions of T lymphocytes. In addition, In vivo experiments verified that PLQT could further inhibit synovial angiogenesis to prevent RA. Conclusion: This study integrated network pharmacology analysis, molecular docking and experimental validation to elucidate the active components of PLQT and its mechanisms in intervening the pathological progression of RA, providing a more comprehensive theoretical basis for the clinical application of PLQT in the treatment of RA.