富血小板血浆联合骨髓间充质干细胞对兔股骨头坏死BMP-2/Smads通路的影响

目的研究富血小板血浆联合骨髓间充质干细胞对兔股骨头坏死BMP-2/Smads通路的影响。方法随机将40只新西兰兔随机分为模型组、富血小板血浆(3%)组、骨髓间充质干细胞(1×106/m L)组、富血小板血浆(3%)+骨髓间充质干细胞(1×106/m L)组。建立兔股骨头坏死模型,术后4w分别向各组股骨头内髓芯减压后注射富血小板血浆、骨髓间充质干细胞。另设空白组10只新西兰兔。空白组与模型组不注射任何物质作为对照。造模后第14周,取材。通过HE染色观察兔股骨头骨髓腔内的病理学及骨陷窝空缺率变化情况。酶联免疫(ELISA)法检测血清中血管内皮生长因子(VEGF)的含量。蛋白免疫印迹(Western blot)法检测股骨头中BMP-2、Smad1、Smad5、Runx2的蛋白水平的变化。结果与模型组相比,各治疗组骨髓腔内骨小梁变粗,脂肪细胞减少,骨细胞增多,骨陷窝空缺率降低(P0.05);各治疗组兔血清VEGF的含量增加,股骨头中BMP-2、Smad1、Smad5、Runx2的蛋白水平提高。结论富血小板血浆与骨髓间充质干细胞可调节BMP-2/Smads信号通路,促进股骨头骨细胞增殖,减少骨陷窝空缺率。

Effect of combination of platelet-rich plasma and mesenchymal stem cells on BMP-2/Smads pathway in rabbits with femoral head necrosis

Objective To investigate the effect of combination of platelet-rich plasma (PRP) with bone marrow mesenchymal stem cells (BMSCs) on BMP-2/Smads pathway in rabbit femoral head necrosis. Methods forty New Zealand rabbits were randomly divided into following groups: model group, PRP (3%) group, BMSCs (1×106/mL) group, and PRP (3%) + BMSCs (1×106/mL) group. A femoral head necrosis model was established. After 4-weeks of the surgery, PRP and BMSCs were injected into the femoral head core of the rabbits after decompression. Another 10 rabbits were set as normal group. Normal and model groups were not injected with any substance used as control. After 14 weeks, the rabbits were sacrificed. HE staining method was used to observe the pathological changes of the femoral marrow cavity and lacuna vacancy rate. The serum level of vascular endothelial growth factor (VEGF) was determined using ELISA method. The protein levels of BMP-2, Smad1, Smad5, and Runx2 in the femoral head were detected using Western blotting method. Results Compared with the model group, the trabecular in marrow cavity widened in the treatment groups. Meanwhile, the adipocytes reduced, as well as the lacuna vacancy rate, but the osteoblasts increased. VEGF content and protein levels of BMP-2, Smad1, Smad5, and Runx2 increased after the treatment. Conclusion PRP and BMSCs promote the proliferation of osteoblasts in the femoral head and reduce the lacuna vacancy rate by regulating the BMP-2/Smads pathway.