Experimental Study On The Effect Of Guizhi Shaoyao Zhimu Decoction On Joint Inflammation And Bone Injury In Rats With Collagen-Induced Arthritis

1.Objective:Guizhi Shaoyao Zhimu Decoction is a common prescription for clinical treatment of rheumatoid arthritis,but its mechanism of action needs further study.This study constructed a rat model of collagen-induced arthritis(CIA),and explored the intervention and mechanism of Guizhi Shaoyao Zhimu Decoction on joint inflammation and bone injury in rats,and provided experimental evidence for its clinical treatment of rheumatoid arthritis.2.Methods:Six of the one hundred Wistar male rats were randomly selected as a blank group,and the rest were used to replicate the arthritis model.The model was replicated by subcutaneous injection of a mixed emulsion of bovine type II collagen and complete/incomplete Freund’s adjuvant.Rats with successful model replication were randomly divided into model group,low-medium-high dose group of Guizhi Shaoyao Zhimu Decoction and methotrexate group.Rat arthritis index,foot volume and footpad thickness were measured regularly;MicroCT scan of knee and ankle joint was performed;rat thymus and spleen index were measured;Serum and synovial homogenate supernatants were detected for RANKL and OPG levels.Knee synovial pathology staining was performed.The effects of Guizhi Shaoyao Zhimu decoction on the above indexes were analyzed statistically.3.Results:1)Guizhi Shaoyao Zhimu Decoction can reduce the arthritis index and foot volume of CIA rats;there is no statistically significant improvement in the thickness of footpad.2)Guizhi Shaoyao Zhimu Decoction can reduce the thymus and spleen index of CIA rats.3)Guizhi Shaoyao Zhimu Decoction can reduce the level of RANKL in the synovial homogenate supernatant of CIA rats,increase the level of OPG in serum and synovial homogenate supernatant,and make serum and synovial homogenate supernatant OPG/ RANKL ratio is increased.4)Guizhi Shaoyao Zhimu Decoction can inhibit the knee joint and ankle jointdestruction and deformity of CIA rats displayed by MicroCT.5)Guizhi Shaoyao Zhimu Decoction can alleviate lining cell proliferation and inflammatory cell infiltration in the synovial of knee joints of CIA rats.4.Conclusion:Guizhi Shaoyao Zhimu Decoction can reduce the thymus and spleen index of CIA rats and has certain immunosuppressive effects.It can reduce arthritis index and foot volume,inhibit lining cell proliferation and inflammatory cell infiltration in the synovial of knee joints,and can regulate RANKL-OPG pathway,so as to delay and inhibit joint inflammation and bone injury.Thereby achieving a therapeutic effect on rheumatoid arthritis.