ABSTRACT
ObjectiveTo observe the effect of Flemiphilippinin D on collagen-induced arthritis （CIA） in rats and explore its mechanism. MethodForty rats were randomly divided into normal group， CIA group， methotrexate （MTX） group （1.35 mg·kg-1）， low-dose Flemiphilippinin D group （1.5 mg·kg-1）， and high-dose Flemiphilippinin D group （3.0 mg·kg-1）， with eight rats in each group. Except for the normal group， the CIA model was induced by type Ⅱ collagen. Each group was given corresponding liquid medicine or normal saline， once a week in the MTX group， and once a day in the Flemiphilippinin D groups for a total of 28 days. The arthritis score and joint swelling degree of rats were experimentally recorded. Pathological changes in the ankle joint of rats were observed by hematoxylin-eosin （HE） staining. Serum levels of inflammatory cytokines interleukin （IL）-1β， IL-6， IL-8， and tumor necrosis factor （TNF）-α were detected by enzyme-linked immunoabsorbent assay （ELISA）， and the mRNA expression of Toll-like receptor 2 （TLR2）， myeloid differentiation factor 88 （MyD88）， and nuclear transcription factor-κB （NF-κB） p65 were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， and the protein expressions of TLR2， MyD88， and NF-κB p65 were detected by Western blot. ResultCompared with the normal group， the ankle joint of the CIA group was significantly swollen， and the clinical score of arthritis and the degree of joint swelling were significantly increased （P<0.01）. The ankle joint tissue structure was significantly damaged， and the levels of inflammatory factors IL-1β， IL-6， IL-8， and TNF-α in serum were significantly increased （P<0.01）. The mRNA levels and protein levels of TLR2， MyD88， and NF-κB p65 were significantly increased（P<0.01）. Compared with the CIA group， arthritis clinical score and joint swelling of rats in each administration group were significantly reduced （P<0.05， P<0.01）， and the pathological changes in the ankle joint were significantly improved. The contents of serum IL-1β， IL-6， IL-8， and TNF-α were significantly decreased （P<0.05， P<0.01）. The mRNA levels and protein levels of TLR2， MyD88， and NF-κB p65 in the ankle joint were significantly decreased （P<0.05， P<0.01）. ConclusionTo a certain extent， Flemiphilippinin D can reduce the expression of inflammatory factors in rheumatoid arthritis rats and play a good therapeutic effect. It works perhaps by inhibiting the activation of the TLR2/MyD88/NF-κB signaling pathway and thus shows an anti-inflammatory effect.