不同剂量转化生长因子-β1对兔颞下颌关节骨关节炎的影响

The effects of different doses of transforming growth factor-β1 on temporomandibular joint osteoarthritis in rabbit model

目的探讨关节腔内注射不同剂量转化生长因子-β1(TGF-β1)对兔颞下颌关节骨关节炎(TMJOA)的影响。方法40只新西兰白兔,随机分为实验组(36只)和对照组(4只)。实验组通过双侧颞下颌关节盘部分切除建立骨关节炎模型,术后4周分别注射20、40和80 ng TGF-β1于右侧颞下颌关节内,左侧关节注射等量生理盐水。注射后6周及12周时,分批处死实验组与对照组动物。获取髁突标本后对软骨与软骨下骨分别行Micro CT检查与糖蛋白含量检测(番红-O染色)。结果术后生理盐水组的关节呈明显的骨关节炎表现,其软骨糖蛋白含量较正常组明显降低,软骨下骨逐渐硬化。注射后6周,所有TGF-β1组糖蛋白含量均高于正常组与盐水组。其中,40 ng与80 ng组糖蛋白含量更高于20 ng组。注射后12周时,所有TGF-β1组关节软骨组织结构有序,其糖蛋白含量无组间差异,虽较6周时有所降低,但仍高于正常组。所有TGF-β1组的软骨下骨都得到显著改善,且具有与正常组类似的软骨下骨细微结构。结论关节腔内注射TGF-β1能够有效地促进TMJOA中病变软骨的修复并阻止软骨下骨异常骨改建。

Objective To investigate the effects of different doses of transforming growth factor-β1 on temporomandibular joint osteoarthritis （TMJOA） in rabbit model. Methods 40 rabbits were randomly divided into experimental group （36） and control group （4）. Partial disc resection was performed bilaterally in 36 rabbits to induce osteoarthritis. Four weeks later, the right joint was injected with 20 ng,40 ng,80 ng TGF- β1 as 20 ng,40 ng,80 ng TGF-β1 groups, and the left joint with physiological saline as physiological saline group. 6 and 12 weeks after injection ,6 animals of each group were sacrificed and the condyle was dissected to be scanned by microcomputed tomography （microCT） and stained with safranin-O to analyze the three dimensional morphology of the subchondral bone and examine the amountof proteoglycan in articular cartilage. Results Joints in physiological saline group after the surgery showed osteoarthritic changes with decreased amount of proteoglycan in articular cartilage and gradually hardened subchondral bone. 6 weeks after injection,all TGF-β1 groups had a higher amount of proteoglycan than the normal group and physiological saline group,and the amount of proteoglycan in 40 ng and 80 ng TGF-β1 groups was higher than that in 20 ng group. At 12 weeks,all TGF-β1 groups had a well-organ-ized fibrocartilage. There was no difference in the amount of proteoglycan between all TGF- β1 groups,while it was still higher than the normal group. The subchondral bones in all TGF-β1 groups have improved and were similar to the normal group. Conclusions Intraarticular injection of TGF- β1 can effectively promote the cartilage repair and prevent abnormal bone remodeling of the subchondral bone in TMJOA.