骨髓间充质干细胞移植治疗肢体缺血的机制

摘要

BACKGROUND:Bone marrow stem cel transplantation has good achievements in the treatment of lower limb ischemic disease, but it mechanism of action is stil unclear. OBJECTIVE:To explore the mechanism of bone marrow mesenchymal stem cel transplantation for treatment of limb ischemia in Sprague-Dawley rats. METHODS:The abdominal aorta, iliac arteries and lumbar arteries below the renal artery were ligated to prepare hind limb ischemia models in female Sprague-Dawley rats. Bone marrow mesenchymal stem cels from male Sprague-Dawley rats were amplified, purified and injected into the rectus femoris of the ischemic right hind limb in female rat models; in the control group, equal volume of normal saline was injected. After transplantation 2, 4, 6 weeks, hematoxylin-eosin staining of the right rectus femoris, immunohistochemical staining of vascular endothelial growth factor and SRY immunohistochemical staining were performed. RESULTS AND CONCLUSION:After operation 2, 4, 6 weeks, the capilary count and the number of cels positive for vascular endothelial growth factor in the transplantation group were significantly higher than those in the control group (P < 0.01). SRY immunohistochemical staining showed positive cels appeared at the capilary n wal, which scattered in the muscle tissue in the transplantation group. These findings indicate that the local injection of bone marrow mesenchymal stem cels can improve the blood supply of ischemic hind limbs in Sprague-Dawley rats. Bone marrow mesenchymal stem cels as paracrine cels can prompt the neovascularization of ischemic limbs in rats by increasing the secretion of vascular endothelial growth factor.%背景：骨髓间充质干细胞移植治疗下肢缺血疾病已取得较好的效果，但其作用机制尚无定论。目的：探讨骨髓间充质干细胞移植治疗SD大鼠后肢缺血的机制。方法：结扎肾动脉下腹主动脉、腰动脉和髂腰动脉制备雌性SD大鼠后肢缺血模型。将扩增、纯化的雄性SD大鼠骨髓间充质干细胞注射入大鼠缺血的右后肢股直肌中，对照组右后肢注射等量生理盐水。移植后2，4，6周，制备大鼠右股直肌切片行苏木精-伊红染色、血管内皮生长因子免疫组织化学染色、SRY基因免疫组织化学染色。结果与结论：移植后2，4，6周移植组右股直肌毛细血管计数、血管内皮生长因子免疫组织化学染色阳性细胞计数均明显高于对照组(P <0.01)。移植组股直肌切片中SRY免疫组织化学染色阳性细胞出现于毛细血管壁，并散在分布于肌组织中。结果表明局部注射移植骨髓间充质干细胞能促进缺血组织迅速生成大量毛细血管，改善大鼠缺血下肢的血供。骨髓间充质干细胞作为旁分泌细胞，通过增加血管内皮生长因子的分泌，促使大鼠缺血肢体的血管新生。