滑膜组织在脐带间充质干细胞治疗骨关节炎中的作用及机制

Role and the mechanism of synovial tissue in the treatment of osteoarthritis by mesenchymal stem cells

目的探讨骨关节炎(OA)兔滑膜的改变及脐带间充质干细胞(UC-MSCs)对OA的治疗作用及相关机制。方法选取健康成年新西兰大白兔15只,分为对照组、OA模型组、UC-MSCs干预组3组,每组各5只。OA造模成功后给予干预组关节腔内注射UC-MSCs,干预4周后观察关节影像学改变及病理学改变;取各组滑膜组织通过免疫组化方法检测滑膜组织IL-6、基质金属蛋白酶-13(MMP-13)等炎症因子的水平及细胞外信号调节激酶(ERK)等表达水平,并采用Western blot方法检测滑膜组织IL-6、MMP-13、ERK、丝裂原活化蛋白激酶(MAPK)蛋白等表达水平。结果磁共振检查显示,与对照组相比,OA模型组兔膝关节滑膜明显增厚,关节腔积液明显增多;UC-MSCs干预组关节滑膜增厚、关节腔积液均较OA模型组明显改善。病理学观察显示,OA模型组关节滑膜炎性细胞较对照组明显增多,滑膜增生、水肿明显,UC-MSCs干预组较OA模型组滑膜炎性细胞浸润减轻,滑膜增生、水肿明显减轻。免疫组化结果显示,OA模型组兔滑膜IL-6、MMP-13、ERK水平较对照组明显升高(P<0.05)。UC-MSCs干预组ERK、MMP-13水平较OA模型组下降,差异有统计学意义(P<0.05),IL-6水平较OA模型组下降不明显,差异无统计学意义(P>0.05)。Western blot结果显示,模型组IL-6、MMP-13、MAPK、ERK表达水平均较对照组明显升高,差异有统计学意义(P<0.05);UC-MSCs干预组IL-6、MMP-13、MAPK、ERK表达量较OA模型组明显下降(P<0.05)。结论OA病程中存在滑膜组织炎症反应改变,滑膜的炎症因子参与OA形成及进展;UC-MSCs对OA兔滑膜具有保护作用,与其抑制炎症反应相关。

Objective To investigate the changes of synovial membrane in osteoarthritis(OA),and to investigate the therapeutic effect of umbilical cord mesenchymal stem cells(UC-MSCs)on OA through synovial membrane and the related mechanism.Methods Fifteen healthy adult New Zealand white rabbits were selected and divided into 3 groups,including control group,OA model group and UC-MSCs intervention group,with five rabbits in each group.After successful OA modeling,intra-articular injection of UC-MSCs was given to UC-MSCs intervention group.Imaging and pathological changes of the joints were observed after 4 weeks of treatment.The expression levels of interleukin-6(IL-6),matrix metalloproteinase-13(MMP-13)and extracellular signal regulated kinase(ERK)proteins in the synovial tissues of rabbits in each group were detected by immunohistochemistry and the protein expression levels of IL-6,MMP-13,ERK and mitogen-activated protein kinase(MAPK)in the synovial tissues of rabbits were detected by Western blot.Results Magnetic resonance examination showed that compared with control group,the synovium of the knee joint in OA model group was significantly thickened and the effusion of the joint cavity was significantly increased;Synovial thickening and joint effusion were significantly improved in UC-MSCs intervention group compared with OA model group.Pathological results showed that the number of synovial inflammatory cells and synovial hyperplasia and edema were significantly increased in OA model group compared with control group.Compared with OA model group,the infiltration of synovial inflammatory cells and synovial hyperplasia and edema were significantly reduced in UC-MSCs intervention group.The levels of ERK,IL-6 and MMP-13 in synovial membrane of rabbit in OA model group were significantly higher than those in control group(P<0.05).The levels of ERK and MMP-13 in UC-MSCs intervention group were decreased compared with OA model group(P<0.05).Western blot analysis showed that the expression levels of IL-6,MMP-13,MAPK and ERK in OA model group were significantly higher than those in control group(P<0.05),while significantly decreased in UC-MSCs intervention group(P<0.05).Conclusions Inflammatory factors of synovial tissue are involved in the formation and progression of OA.UC-MSCs has a protective effect on the synovial membrane of OA,which is related to the inhibition of inflammatory response.