木瓜蛋白酶对兔膝关节骨关节炎滑膜病变的诱导作用

Induction of papain on pathological changes of rabbit synovium in knee osteoarthritis model

目的探讨木瓜蛋白酶诱导兔膝关节骨关节炎模型的滑膜病理变化。方法纳入30只新西兰大白兔,随机分为对照和模型组,模型组动物均采用木瓜蛋白酶注射方式制备膝关节骨关节炎模型,术后2、4、6周,分别取两组各5只动物,处死后获得滑膜组织标本,观察一般情况,对两组不同时间的滑膜进行Mankin评分;苏木精-伊红(HE)染色观察病理变化;酶联免疫法检测滑膜血管内皮生长因子(VEGF)和白细胞介素-1β(IL-1β)表达水平。结果木瓜蛋白酶单次注射后第2周,对模型组动物进行病理观察,可见膝关节出现严重的滑膜炎性反应,滑膜细胞与下层疏松纤维及血管组织均明显增生,并存在大量淋巴浆细胞浸润;随着时间推移,炎性反应逐渐减轻。随着注射时间的延长,模型组Mankin评分、VEGF和IL-1β表达水平均呈下降趋势,对照组无明显变化;模型组木瓜蛋白酶注射后2、4周的Mankin评分、VEGF和IL-1β表达水平均显著高于对照组(P<0.05),注射后6周的Mankin评分、VEGF和IL-1β表达水平与对照组化比较差异无统计学意义。结论木瓜蛋白酶可以诱导兔膝关节骨关节炎模型,木瓜蛋白酶单次注射后第2周,兔膝关节滑膜炎性反应严重,第4、6周时炎性反应逐渐减轻。

Objective To investigate the effect of papain on pathological changes of synovial membrane in knee osteoarthritis rabbit model. Method Totally 30 New Zealand white rabbits were randomly divided into control group and model group with 15 rabbits in each group. Two groups of five animals were sacrificed to, obtain membrane tissue for observation in two, four and six weeks after operation. Two groups of synovium were evaluated by Mankin score at different time. Hematoxylin eosin（HE） staining was used to observe pathological changes. The expression level of vascular endothelial growth factor（VEGF） and interleukin-1 beta（IL-1β） in synovial membrane were detected by ELISA. Results Papain once injection after two weeks, the animals of model group were observed. The visible knee appeared serious inflammatory reaction, synovial cells, lower loose fibrous tissue, and blood vessels were significantly hyperplasia, and there was a large amount of lymphoplasmacytic infiltration. As time goes on, the inflammatory response was gradually reduced. With the extension of injection time, Mankin score, VEGF and IL-1β expression levels of model group showed a declining trend, but no apparent change in the control group. Mankin score, VEGF and IL-1β expression levels of model group after two and four weeks papain injection were significantly higher than those in control group（P 0.05）. Six weeks after the injection, Mankin score, VEGF and IL-1β expression levels had no significant difference compared with control group. Conclusion Papain can induce knee osteoarthritis in rabbit models. Two weeks after a single injection of papain, the inflammatory reaction of knee joint synovitis is serious in rabbits, and the inflammatory reaction is gradually alleviated after four and six weeks.