| 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. |