Study on the mechanism of action of traditional Chinese medicine compound Wu Mei Pill in inhibiting rheumatoid arthritis through TLR4-NF-κB pathway

Abstract

Abstract Background Wu Mei Pills (WMP) is a traditional Chinese medicine compound with good anti-inflammatory effects. It is used in Chinese medicine theory to treat diseases such as wind, cold. Rheumatoid arthritis (RA) belongs to the “Bi” syndrome caused by wind and cold in traditional Chinese medicine. WMP has been documented for treating RA, but its mechanism of action on RA is still unclear. Aim of the study This experiment mainly explores the mechanism of WMP on collagen-induced rheumatoid arthritis model in rats (CIA rat), as well as the mechanism of inflammation, migration and invasion of fibroblasts like synovial cells (RA-FLS). Materials and methods Analyze the chemical composition of WMP through UPLC-MS. Then, the intrinsic mechanism of WMP was analyzed by ELISA, cell scratch, Transwell, and Western blotting. Finally, WMP was applied to CIA rats to further explore the mechanism of WMP inhibiting RA. Result The UPLC-MS results indicate that WMP contains 181 compounds. Serum containing WMP (2%, 8%) plays an important role in inhibiting the migration and invasion mechanisms of RA-FLS. The intrinsic mechanism is to decrease matrix metalloproteinases (MMP-2) and MMP-9 and increase the protein expression of their complexes TIMP-1, TIMP-2 in RA-FLS. At the same time, WMP also reduced TNF and IL-6 levels in RA-FLS- α, acting through inhibition of TLR4-NF-κB inflammatory pathway activation. In in vivo experiments, WMP (0.5g/kg, 2kg/kg) alleviated arthritis and immune organ indices in type II collagen-induced rheumatoid arthritis model-CIA rats. Pathological section results showed that WMP suppressed knee joint swelling and inflammatory infiltration in CIA rats. Conclusions WMP plays a significant role in alleviating the course of RA. The specific mechanism is to inhibit the classical TLR4-NF-κB inflammatory pathway and reduce the secretion of inflammatory factors in the serum of RA -FLS and CIA rats. In addition, it regulates the dynamic balance of MMP-2/TIMP-2, MMP-9/TIMP-1, modulates the mechanism of RA-FLS invasion, and protects articular cartilage tissues in RA.