Effects and mechnism of abnormal stress promoting MIF,COX2 and PGE2 in the progression of temporomandibular joint osteoarthritis / 解放军医学杂志

ABSTRACT

Objective To investigate the effects and mechnism of abnormal stress promoting macrophage mobility inhibitory factor(MIF),cyclooxygenase 2(COX2)and prostaglandin E2(PGE2)in the progression of temporomandibular joint osteoarthritis(TMJOA).Methods From January 2020 to December 2021,TMJOA and temporomandibular joint internal derangement(TMJID)patients(30 cases in each group,we divided the TMJOA into group TMJ Ⅰ,Ⅱ,Ⅲ according to the stage)who were admitted to TMJOA special clinic of the First Affiliated Hospital of Xinjiang Medical University and accompanied by abnormal occlusion were collected.The pain score of the occlusal state of the patients was evaluated by visual analogue scale.The expression levels of MIF,COX2 and PGE2 in synovial fluid were detected by ELISA.We used the unilateral anterior crossbite for TMJOA(UAC)rats model(the grouped intoUAC-4 weeks,UAC-8 weeks and UAC-12 weeks group),and control group at the same time(grouped intoCtrl-4 weeks,Ctrl-8 weeks and Ctrl-12 weeks group),each group had 6 rats.The expression levels of MIF,COX2 and PGE2 in serum and synovial fluid of rats were detected by ELISA.The expression levels of IL-1β,IL-18,MIF,COX2 and PTGER2 in temporomandibular joint of rats were detected by Western blotting.The fluid flow shear stress(FFSS)model of fibroblast-like synovial cells(FLSs)was established,and the mRNA and protein expression levels of above indexes were detected by RT-PCR and Western blotting.Results Visual analogue scale evaluation showed that the pain score of TMJOA Ⅰ and Ⅱ group was significantly higher than that of TMJID(P<0.001).ELISA results showed that the expression levels of MIF,COX2 and PGE2 in synovial fluid in TMJOA group were higher than those in TMJID group(P<0.05),and the expression levels were the highest in TMJOA Ⅱ group.Compared with control group,the expressions of MIF,COX2 and PGE2 in serum and synovial fluid at UAC-4 weeks,8 weeks and 12 weeks were slightly higher,and significantly higher at UAC-8 weeks in rat TMJOA model(P<0.05).In addition,the expression trend of protein levels in temporomandibular joint tissues was similar,which showed higher expression levels of IL-1β,IL-18,MIF,COX2 and PTGER2(P<0.05).In the cell model where FFSS interfered with FLSs,with the increase of FFSS,cell with deformation,incomplete cell membrane and reduced number.Compared with control group,the expression levels of IL-1β,IL-18,MIF,COX2 and PGE2(PTGER2)of FLSs were increased in 1,3,5 and 10 dyn/cm2 intervention groups(P<0.05).Conclusion MIF,COX2 and PGE2 were highly expressed in temporomandibular joint synovial fluid of TMJOA patients with malocclusion.And these three factors were also highly expressed in serum and synovial fluid of UAC rats.The abnormal fluid shear stress promotes the secretion of MIF,COX2 and PGE2 by FLSs to participate in joint microenvironment inflammation and accelerate disease progression.