The Effects And Mechanism Of Ethyl Pyruvate On Adjuvant-induced Arthritis Of Rats

Objective:To explore the effects and it's molecular machnism of ethyl pyruvate on adjuvant-induced arthritis(AA)rats.Methods:(1)Forty eight male SD rats were separated as normal group(group A),model group(group B),ethyl pyruvate group(group C). Group B and C were induced arthiritis by injected complete Freund's adjuvant.Group C was administered with intraperitoneal injection ethyl pyruvate 50 mg/kg twice a day for 36 days starting from the day of injection of complete Freud's adjuvant.Paw inflammation was assessed by arthritis index.Lesions of bone and cartilage were evaluated on the basis of histological change in ankle joint,radiographic analysis in hind paw with Larsen score.Systemic TNF-αand IL-1βlevels were measured by ELISA.(2)The inflammatory of fibroblast-like synoviocytes was induced by tumor necrosis factor(TNF)-α.The effects of ethyl pyruvate on interleukin(IL)-6 were detected by ELISA.RESULTS:(1)Ethyl pyruvate group lived well and had weaker arthrocele and low degree of bone destruction.Intervention group of ethyl pyruvate in 50mg/kg/d improved obviously on arthritis index, histopathology of synovial membrane and changes of radiology than model control groups.(P＜0.05),and obvious advert effects were not observed.(2)EP group had lower levels of TNF-αand IL-1βthan model group(P＜0.05)and had higher levels of TNF-αand IL-1βthan normal group.(P＜0.05).(3)Ethyl pyruvate alone has no effect on the secrection of IL-6,but ethyl pyruvate can reduced the secretion of IL-6 induced by TNF-α.CONCLUTIONS:(1)Ethyl pyruvate in dose of 50mg/kg/d can improve the arthritis symptoms,lower synovial inflammation and destruction of bone of the adjuvant-induced arthritis(AA)rats.(2)Ethyl pyruvate can lower the level of TNF-αand IL-1βin the blood serum of AA rats.(3)EP can inhibit the secretion of IL-6 of RA fibroblast-like synoviocytes induced by TNF-α.