移植人羊膜间充质干细胞促进脊髓损伤大鼠神经功能恢复

目的研究移植人羊膜间充质干细胞（hAMSCs）是否促进脊髓损伤大鼠神经功能恢复,探索其可能作用机制。 方法60只雌性SD大鼠按照随机数字表法分为磷酸盐缓冲液（PBS）治疗组（30只）和hAMSCs治疗组（30只）。脊髓损伤采用脊髓撞击损伤模型,hAMSCs或PBS立刻移植到离脊髓损伤中心2 mm的头尾两端。免疫荧光检测细胞分化,血管再生和轴突再生。酶联免疫吸附剂测定试剂盒检测脑源性神经营养因子（BDNF）和血管内皮生长因子（VEGF）含量,BBB运动功能评分检测行为学。 结果在脊髓损伤后14 d、21 d和28 d,hAMSCs治疗组BBB评分分别为（8.75±0.701）、（10.375±0.532）和（12.125±0.350）,高于PBS组（6.0±0.463）、（7.25±0.412）和（9.125±0.440）,差异具有统计学意义（P<0.05）。在第7天和第14天,hAMSCs治疗组BDNF表达水平分别为（75.138±4.367）pg/mg和（66.483±4.099）pg/mg,高于PBS组（43.901±3.607）pg/mg和（41.108±3.848）pg/mg,差异具有统计学意义（P<0.05）。在第7天,第14天和第28天,hAMSCs治疗组VEGF表达水平分别为（23.328±2.463）pg/mg,（22.301±2.223）pg/mg和（14.855±1.282）pg/mg,高于PBS组（9.978±1.572）pg/mg,（9.271±1.496）pg/mg和（7.113±1.123）pg/mg,差异具有统计学意义（P<0.05）。hAMSCs治疗组血管数目（17.5±2.102）高于PBS组（6.25±1.750）,差异具有统计学意义（P<0.05）。hAMSCs治疗组小鼠抗5羟色胺阳性神经纤维面积（3486±203.643）和GAP43阳性神经纤维面积（4568.25±253.881）高于PBS组（2070.25±156.344）和（2455.725±314.475）,差异具有统计学意义（P<0.05）。 结论移植hAMSCs能促进脊髓损伤大鼠神经功能恢复,其作用机制可能是通过增加神经营养因子表达,促进血管再生和轴突再生。因此hAMSCs移植是治疗脊髓损伤的理想方法。

Transplantation of human amniotic mesenchymal stem cells promotes functional recovery in a rat model of traumatic spinal cord injury

ObjectiveTo assess whether hAMSCs transplantation promotes neurological functional recovery in rats after traumatic spinal cord injury (SCI). In addition, the potential mechanisms underlying the possible benefits of this therapy were investigated. MethodsA total of 60 Female Sprague-Dawley rats were divided into PBS group and hAMSCs group (n=30). The SCI models were induced by a weight Drop device and then hAMSCs, or phosphate buffered saline (PBS) were immediately injected into the contused dorsal spinal cord at 2 mm rostral and 2 mm caudal to the injury site. Immunohistochemistry were performed to assay differentiation, angiogenesis and axonal regeneration. The expressions of BDNF and VEGF were analyzed by ELISA. Hind limb motor function was assessed with Basso, Beattie and Bresnahan (BBB) locomotor rating scale. ResultsAt 14, 21 and 28 d after SCI, BBB scores (8.75±0.701, 10.375±0.532, 12.125±0.350) of the hAMSCs group were significantly higher than that of PBS group(6.0±0.463, 7.25±0.412, 9.125±0.440) (P<0.05). At 7 and 14 d after SCI, the levels of BDNF (75.138±4.367 pg/mg, 66.483±4.099 pg/mg) of the hAMSCs group were significantly higher than that of PBS group (43.901±3.607 pg/mg, 41.108±3.848 pg/mg) (P<0.05). At 7, 14 and 28 d after SCI, the levels of VEGF (23.328±2.463 pg/mg, 22.301±2.223 pg/mg, 14.855±1.282 pg/mg) were significantly higher than that of PBS group (9.978±1.572 pg/mg, 9.271±1.496 pg/mg, 7.113±1.123 pg/mg)(P<0.05). The number of vWF+ blood vessels 17.5±2.102 in the hAMSCs group was significantly higher than that in PBS group 6.25±1.750(P<0.05). The 5HT+ fiber area 3486±203.643 and GAP43+ fiber area 4568.25±253.881 in the hAMSCs group were significantly higher than that in PBS group (2070.25±156.344, 2455.725±314.475) (P<0.05). ConclusionhAMSCs transplantation significantly enhanced neurological function in rats after SCI. This enhanced neurological function may be due to increased expression of neurotrophic factors and both angiogenesis and axonal regeneration. Thus, hAMSCs transplantation appears to be promising in the treatment of SCI.