放射抑制小鼠骨髓间充质干细胞成骨潜能并导致骨损伤

目的 观察放射对小鼠骨髓间充质干细胞(BMMSCs)体外成骨潜能及体内骨组织的影响.方法 分离、培养正常的及接受4Gy放射后28d的小鼠BMMSCs,用碱性磷酸酶(ALP)和Von Kossa染色法鉴定BMMSCs体外成骨分化潜能的改变,并通过骨组织形态学和骨密度(BMD)检测放射后小鼠体内骨组织的相关变化.结果 4Gy照射28d后小鼠BMMSCs的成骨潜能明显降低,同时体内骨组织结构破坏,小鼠骨密度降低.结论 放射损伤后小鼠BMMSCs的成骨潜能显著降低,可能在干细胞水平参与了放射后骨损伤的发生.

Impairment of osteogenesis potential of bone marrow mesenchymal stem cells and bone injury caused by irradiation

Objective To investigate the effects of irradiation on the osteogenesis potential of bone marrow mesenchymal stem cells (BMMSCs) and EM>in vivo/EM> bone system. Methods At 28 days after 4Gy total body irradiation (TBI), BMMSCs were isolated from irradiated or normal male C57BL/6 mice and cultured. Their osteogenesis potential was evaluated by alkaline phosphatase (ALP) and Von Kossa staining after 1 and 3 weeks osteogenic differentiation EM>in vitro/EM> respectively. Bone histomorphometric analysis including hematoxylin and eosin (HE) and toluidine blue staining, bone mineral density (BMD) measurment were performed to detect the changes in bone systemEM>in vivo/EM>. Results Significant impairment of osteogenic differentiation of BMMSCs at 28 days post irradiation was observed in both ALP and Von Kossa staining with less ALP positive cells after 1 week of culture in osteogenic culture and a calcium less mineralized matrix in the induction dish after 3 weeks of induction. Meanwhile, the trabecular structure was gradually fragmented after irradiation and at 15 weeks after TBI, the irradiated mice had decreased total body bone mineral density. Conclusion Irradiation resulted in decrease in osteogenesis potential of BMMSCs accompanied by bone injury, and the damage in BMMSCs may be, at the stem cell level, invo