低氧诱导骨髓基质干细胞移植治疗激素性股骨头坏死

Treatment of steroid-induced femoral head necrosis by hypoxia-induced bone marrow stromal stem cell transplantation

背景:现阶段已经对骨髓基质干细胞移植治疗股骨头坏死进行了探索,但是存在治疗效果不理想等问题。目的:通过对骨髓基质干细胞进行低氧预处理,观察其治疗兔激素性股骨头坏死的效果。方法:抽取新西兰兔髂骨骨髓进行骨髓基质干细胞分离、纯化和培养,放入低氧培养箱(氧气体积分数为2%)中48h进行低氧预处理,采用CCK-8实验、流式细胞术、ELISA检测低氧对细胞活性、细胞凋亡以及分泌细胞因子水平的影响。将40只新西兰兔随机分为对照组、模型组、干细胞组和低氧处理干细胞组,每组10只,后3组建立激素性股骨头坏死模型,后2组在股骨头部位移植正常培养或低氧预处理的骨髓基质干细胞,移植治疗6周后取出股骨头组织,进行大体观察和苏木精-伊红染色。结果与结论:(1)低氧处理后骨髓基质干细胞活力显著增加,细胞凋亡显著降低,释放至上清液中的血管内皮生长因子、肝细胞生长因子和胰岛素样生长因子1水平显著增加;(2)模型组兔股骨头表面软骨破坏、塌陷,表面颜色暗黑、充血,骨质变脆,干细胞组股骨头表面颜色变浅,充血范围减小,低氧处理干细胞组股骨头表面光滑、平整,股骨头颜色浅淡,无明显充血现象,接近于正常;(3)对照组骨小梁结构完整,破骨细胞均匀分散;模型组骨小梁消失明显,出现空骨陷窝,可见大量破骨细胞;干细胞组骨小梁模糊不清,破骨细胞仍密集排布;低氧处理干细胞组骨小梁结构保存较完整,破骨细胞积聚减少;(4)结果表明,低氧预处理的骨髓基质干细胞移植对激素性股骨头坏死具有更好的治疗效果。

BACKGROUND: Bone marrow stromal stem cell transplantation has been explored for the treatment of femoralhead necrosis at present, but there are some problems to be solved such as unsatisfactory therapeutic effect.OBJECTIVE: To observe the effect of hypoxic preconditioning of bone marrow stromal stem cells on steroid-induced femoral head necrosis in rabbits.METHODS: Rabbit bone marrow stromal cells were isolated, purified and cultured. They were cultured in a hypoxic incubator (2% O2) for 48hours. Cell counting kit-8, flow cytometry, and ELISA assay were used to detect cell viability, apoptosis and secretion of cytokines,respectively. Forty New Zealand rabbits were randomly divided into control group, model group, stem cell group and hypoxia-treated stem cellgroup, 10 in each group. Steroid-induced femoral head necrosis model was established in the latter three groups. Bone marrow stromal stemcells that were normally cultured or induced by hypoxia were transplanted in the latter two groups. After 6 weeks of transplantation, femoralhead tissue from each rabbit was taken out for general observation and hematoxylin-eosin staining.RESULTS AND CONCLUSION: (1) After hypoxic preconditioning, the viability of bone marrow stromal stem cells increased significantly,while the cell apoptosis decreased considerably. The levels of cytokines such vascular endothelial growth factor, growth factor and insulin-likegrowth factor 1 released into the supernatant increased markedly. (2) The surface of the femoral head of the model group was damaged andcollapsed. The surface of the femoral head of the model group was dark in color and congested, and the bone became brittle. The surface ofthe femoral head of the stem cell group was light-colored, and the congestion alleviated. The surface of the femoral head of thehypoxia-treated stem cell group was smooth, flat and light-colored, with no obvious congestion. In this group, the femoral head was close tothe normal bone of the control group. (3) In the control group, the trabecular structure was intact and osteoclasts were evenly dispersed. In themodel group, the trabeculae disappeared obviously, and empty bone lacunae appeared. A large number of osteoclasts were observed. In thestem cell group, the trabeculae were blurred and the osteoclasts were still densely arranged. In the hypoxia-treated stem cell group, thetrabecular structure remained intact and the accumulation of osteoclasts decreased. These results suggest that the transplantation of bonemarrow stromal stem cells after hypoxic preconditioning has a better effect on the treatment of steroid-induced avascular necrosis of thefemoral head.