This study was performed to evaluate the effectiveness of mesenchymal stem cells (MSCs) on bone healing and to assess the role of various chemical stimulants and mediators in healing. Forty female mice were randomly assigned to 4 groups (10 mice each) after the induction of fixed fractures: group I: received fixation only; group II: received phosphate-buffered saline (PBS); group III: received intralesion MSCs (IL-MSCs); and group IV: received intraperitoneal MSCs (IP-MSCs). Serum alkaline phosphatase (ALP) levels and the expression of the osteocalcin (OCN), bone morphogenetic protein-2 (BMP-2), and stromal-derived factor-1 (SDF-1) genes were measured. ALP reached baseline level only in IL-MSCs, whereas OCN reached baseline level in MSCs recipients (IL-MSCs and IP-MSCs). BMP-2 significantly increased in MSCs recipients 3 weeks postfracture and increased in all groups 8 weeks postfracture with significant increases in MSC recipients than the fixation and PBS groups. The highest BMP-2 expression was reached in IL-MSC group. MSCs either locally or systemically improves or accelerates the healing of bone fractures with better results obtained after local injection, as shown by biochemical, radiological, and histological findings. MSCs are effective candidates for bone regeneration.

中文翻译：

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骨髓间充质干细胞对骨折愈合的影响

本研究旨在评估间充质干细胞 (MSC) 对骨愈合的有效性，并评估各种化学兴奋剂和介质在愈合中的作用。40只雌性小鼠在诱导固定骨折后随机分为4组（每组10只）：I组：仅接受固定；第二组：接受磷酸盐缓冲液（PBS）；第三组：接受病灶内MSCs（IL-MSCs）；第四组：接受腹腔内MSCs（IP-MSCs）。测量了血清碱性磷酸酶 (ALP) 水平和骨钙素 ( OCN )、骨形态发生蛋白-2 ( BMP-2 ) 和基质衍生因子-1 ( SDF-1 ) 基因的表达。ALP 仅在 IL-MSCs 中达到基线水平，而OCNMSCs 受体（IL-MSCs 和 IP-MSCs）达到基线水平。BMP-2在 MSCs 受者中在骨折后 3 周显着增加，在所有组中在骨折后 8 周均增加，MSC 受者比固定组和 PBS 组显着增加。IL-MSC组BMP-2表达最高。MSCs 局部或全身改善或加速骨折愈合，局部注射后获得更好的结果，如生化、放射学和组织学发现所示。间充质干细胞是骨再生的有效候选者。