Effects Of SQDG On Collagen-induced Arthritis In Rat And The Possible Mechanism

OBJECTIVETo study the effects of SQDG on the secondary inflammation and immune reactions on collagen-induced arthritis(CIA ), In this article, we focus on monocyte/macrophage(Mo/Mφ)and explore the possible mechanisms.METHODSChicken typeⅡcollagen was used to induce CIA in rats, through detection the volume of uninduced-inflammation paws of rats, arthritic scores and tenderness of uninduced-inflammation paws to evaluate occurrence status of arthritis, and observating the diversity of thymus index and spleens index. T,B lymphocytes proliferation was determined by 3-(4,5-dimethylthiazal-2yl) 2,5- diphenyltetrazoli- umbromide(MTT) assay , interleukin-1(IL-1) activity production release from PMФand interleukin-2(IL-2) activity production of splenocytes was measured by thymocyte proliferation assay. anti-Ⅱcollagen antibody in blood was detected by ELISA assay. Applied Ficoll density gradient centrifugal method to separate peripheral blood mononuclear cell(PBMC) , adherence method to obtain monocyte/macrophage(Mo/Mφ),through the experiment of Neutral red phagocytosis detection the phagocytosis function Of Mo/Mφ; IL-1 activity from Mo/Mφwas measured by thymocyte proliferation assay. Through MTT assay to test proliferation function of peripheral blood T lymphocytes which incubated with Mo/Mφaffectd by SQDG. RESULTS1,SQDG could alleviate the secondary inflammation in joint , regulate the fuction of immunity,and have apparently treatment effect to CIA rat.Rats occurrenced red swelling of the paws on d14 after immunity, crest-time of secondary inflammation was on d22, and the inflammation began abatement on d26. SQDG(21.25,42.5,85mg.kg-1, d14～d28) ig could mitigate the inflammation of joint at different degree and could decrease thymus index, spleens index of CIA rats. The further study demonstrated that SQDG(21.25,42.5,85mg.kg-1, d14～d28) ig could suppress the excessive T and B lymphocytes proliferation and over-production of IL-1 and interleukin-2(IL-2) ,.and decrease the elevated anti-Ⅱcollagen antibody in blood.2,The effect of SQDG on the fuction of Mo/Mφfrom normal rats and CIA rats at different inflammation period in vivo studiesThe study on Mo/Mφshowed SQDG (21.25,42.5,85mg.kg-1, d14～d28) ig could enhance phagocytosis function of Mo/Mφfrom normal rats and suppress the augmented phagocytosis function of Mo/Mφfrom CIA rats , cut down over-production of IL-1 to normal level.3,The effect of SQDG on the fuction of Mo/Mφfrom normal rats and CIA rats at different inflammation period, and the proliferation of T lymphocytes co-cultured with Mo/Mφwhich had been co-cultured with SQDG in vitro studiesAdministration SQDG(10,20,40,80,160mg.L-1) in vitro could enhance the phagocytosis function of Mo/Mφof normal rats ,didn't affect the production of IL-1,the proliferation of T lymphocyte cells from peripheral blood co-cultured with the Mo/Mφwhich had been co-cultured with SQDG didn't be affected in normal rats . d7 administration SQDG(10,20,40,80,160mg.L-1) in vitro could cut down the phagocytosis function of Mo/Mφand over-production of IL-1 of CIA rats,however it had little influence to the proliferation of T lymphocytes co-cultured with Mo/Mφwhich had been co-cultured with SQDG; d15,d23 SQDG could cut down the phagocytosis function of Mo/Mφand over-production of IL-1 of CIA rats; and could suppress the proliferation of T lymphocytes co-cultured with Mo/Mφwhich had been co-cultured with SQDG.CONCLUSIONS1. SQDG has an apparently treatment effects on CIA rats;the therapeutic action is related to its immunoregulatory actions.2. SQDG maybe regulate the disnormal fuction of immunity in CIA through adjusting the fuction of Mo/Mφ.