骨髓间充质干细胞对继发性骨质疏松大鼠骨缺损愈合的影响

目的：探讨骨髓间充质干细胞(BMSCs)在继发性骨质疏松性的个体骨缺损愈合过程中的作用。方法采用全骨髓贴壁分离法培养原代BMSCs细胞，并使用流式细胞仪检测及使用成骨成脂特异性染色鉴定培养的BMSCs；选取60只雌性SD大鼠，通过肌注地塞米松(DEX，1 mg·kg-1·d-1)8周，建立大鼠骨质疏松模型。所有大鼠经手术于胫骨平台下钻孔造骨缺损模型，将大鼠随机分成三组：对照组(NS组，骨折不处理)、DEX骨折+生理盐水(NS)组、DEX+BMSCs组，将BMSCs注射到大鼠骨缺损部位治疗(采用生理盐水进行对照)，于术后4周和8周，采用Micro-CT检测各组大鼠的骨缺损愈合情况。结果经流式细胞表型鉴定及成骨成脂特异性染色实验均证实分离得到的细胞是BMSCs。Micro-CT结果表明，与DEX+NS组比较，BMSCs细胞治疗能促进DEX诱导的骨质疏松性骨折的愈合。结论 BMSCs对继发性骨质疏松性大鼠的骨缺损具有显著的促进愈合作用，这为临床治疗继发性骨质疏松个体的骨损伤提供了一种新的研究思路。

Effect of bone marrow-derived mesenchymal stem cells on bone defect healing in rats with secondary osteoporosis

Objective To assess the therapeutic effect of bone marrow-derived mesenchymal stem cells (BM-SCs) in bone defect healing in rats with secondary osteoporosis. Methods Primary BMSCs were cultured by whole bone marrow adherence method, and the BMSC was detected and identified by flow cytometry and osteogenic specific staining. Sixty female SD rats were selected and injected intramuscularly of dexamethasone (DEX, 1 mg·kg-1·d-1) for 8 weeks to establish rat models of osteoporosis. Then the rats were drilled under the tibial plateau to establish bone defect models. The rat models were randomly divided into three groups, control group NS group (fracture was not treated), DEX fracture combined with saline (DEX+NS group), DEX fracture combined with BMSCs treatment group (DEX+BMSCs group). BMSCs were injected into the bone defect site for treatment (saline was used as control). Micro-CT was used to detect bone defect healing of the rats in each group 4 and 8 weeks after surgery. Results Flow cytometry and os-teogenic specific staining both confirmed that the isolated cells were BMSCs. Micro-CT results showed that BMSCs treat-ment can promote the healing of osteoporotic fracture induced by DEX, compared with DEX fracture combined with NS. Conclusion BMSCs has a significant role in promoting the healing of bone defect in secondary osteoporotic rats, which provides a new approach for clinical treatment of individual bone defect in the patients with secondary osteoporosis.