分区式脊髓导管联合骨髓基质干细胞修复脊髓横断损伤模型大鼠

Partition-type spinal cord catheter combined with bone marrow stromal stem cells in the repair of spinal cord transection injury in rats

背景:脊髓损伤致残率高,治疗上仅限于早期手术干预、药物治疗和后期功能锻炼等手段,运动功能稍有改善,但目前尚无有效治愈办法。目的:探讨分区式脊髓导管和骨髓基质干细胞联合对大鼠T8脊髓全横断损伤模型的修复效果。方法:根据数字表法将50只大鼠随机分为5组,每组10只,Ⅰ组为T8脊髓全横断切除5 mm,不做其他处理;Ⅱ组为造模后将分区式脊髓导管植入形成的缺损内;Ⅲ组为造模后将分区式脊髓导管植入形成的缺损内,同时植入骨髓基质干细胞;Ⅳ组为造模后将分区式脊髓导管植入形成的缺损内,同时植入聚乙醇酸纤维;Ⅴ组为造模后将分区式脊髓导管植入形成的缺损内,同时植入骨髓基质干细胞和聚乙醇酸纤维。结果与结论:(1)术后2周和12周Ⅲ组和Ⅴ组的BBB评分明显高于Ⅰ组、Ⅱ组和Ⅳ组,差异有显著性意义(P<0.05)。(2)术后12周Ⅴ组损伤平面以下运动诱发电位的潜伏期明显少于Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组,差异有显著性意义(P<0.05)。(3)免疫组化显示Ⅲ组和Ⅴ组在导管中间能找到染色阳性的再生神经纤维并生长有序,无明显缠绕成团的现象。(4)透射电镜显示桥接各组都有一定数量的有髓神经纤维。(5)结果表明分区式壳聚糖脊髓导管联合骨髓基质干细胞植入可以较好的连接脊髓损伤缺损,恢复一部分电生理特性,加快轴突再生,恢复运动功能,为脊髓损伤的治疗提供了一个新的方向。

BACKGROUND： There is a high morbidity after spinal cord injury, and the therapeutic strategy is limited to early surgical intervention, medication and post-treatment exercise that only can improve the motor function slightly. However, there is no effective cure method. OBJECTIVE： To study the effect of partition-type spinal cord catheter combined with bone marrow stromal stem cells on T8 spinal cord transection damage in rats. METHODS： Fifty rats were randomized into five groups（n=10 per group）： group I, T8 spinal cord transection（5 mm） was made in rats with no treatment; group II, the partition-type tube was inserted into the injured site after modeling; group III, partition-type tube combined with bone marrow stromal stem cells was implanted into the injured site after modeling; group IV, partition-type tube combined with polyglycolic acid fibers was implanted into the injured site after modeling; group V, partition-type tube combined with bone marrow stromal stem cells and polyglycolic acid fibers was implanted into the injured site after modeling. RESULTS AND CONCLUSION： At 2 and 12 weeks postoperatively, Basso, Beattie and Bresnahan scores were significantly higher in the groups III and IV than the groups I, II, IV（P〈0.05）. At 12 weeks postoperatively, the latency of motor evoked potential below the injury plane was significantly decreased in group V compared with groups I, II, III, IV（P〈0.05）. Immunohistochemical results displayed that in the groups III and V, regenerated nerve fibers grew positively and arranged orderly among the tubes, and there was no obvious winding phenomenon. Under transmission electron microscopy, a certain number of myelinated nerve fibers were found as bridges among groups. These findings indicate that the partition-type chitosan tube combined with bone marrow stromal stem cells has a good connection with the injured spinal cord a good connection to restore part of electrophysiological properties, accelerate the axon regeneration, recover the motor function, thereby providing a new direction for the treatment of spinal cord injury.