脑红蛋白修饰的骨髓间充质干细胞在促红细胞生成素治疗大鼠急性脊髓损伤中的作用

目的探讨脑红蛋白(neuroglobin,Ngb)修饰的骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)在促红细胞生成素(erythropoietin,EPO)治疗大鼠急性脊髓损伤中的作用。方法清洁级雄性SD大鼠36只(湖南斯莱克景达实验动物有限公司),体重250~300g。随机分为3组,各12只,建立脊髓损伤模型后不予以特殊处理(不处理组);在建立脊髓损伤模型术后30min予以腹腔注射EPO治疗(EPO组);在脊髓损伤模型造模后立即予以10μL Ngb修饰的BMSCs悬液局部注射,造模术后30min予以腹腔注射EPO(BMSCs悬液局部注射组)。统计分析造模后3、7d的脊髓损伤行为学评分、脊髓组织细胞凋亡率以及血清肿瘤坏死因子(TNF)-α与白介素(IL)-6、脊髓组织丙二醛(MDA)水平。结果BMSCs悬液局部注射组造模后3、7d的脊髓损伤行为学评分(BBB)(5.33±0.77)分、(6.72±0.81)分]显著高于EPO组与不处理组(5.18±0.80)分、(5.87±0.82)分和(4.09±0.77)分、(5.47±0.89)分,P<0.05],EPO组造模后7d的BBB评分显著高于不处理组(P<0.05)。BMSCs悬液局部注射组造模后3、7d的脊髓组织细胞凋亡率均显著高于EPO组与不处理组(P<0.05),造模后7d EPO组与不处理组对比差异亦有统计学意义(P<0.05)。EPO组与BMSCs悬液局部注射组造模后3、7d的血清肿瘤坏死因子(TNF)-α、白介素(IL)-6、脊髓组织丙二醛(MDA)水平均显著低于不处理组(P<0.05),BMSCs悬液局部注射组造模后7d的MDA表达水平显著低于EPO组(P<0.05)。结论Ngb修饰的BMSCs在EPO治疗大鼠急性脊髓损伤中的应用能抑制炎症因子的表达与脂质过氧化,抑制细胞凋亡,从而促进神经功能的恢复。

The role of Ngb modified BMSCs in the treatment of acute spinal cord injury in rats treated with EPO

Objective To investigate the role of brain erythropoietin(Ngb)modified bone marrow mesenchymal stem cells(BMSCs)combined with erythropoietin(EPO)in the treatment of acute spinal cord injury in rats.Methods 36 male Sprague-Dawley rats weighted 250-300g were randomly and equally divided into group A,group B and group C,with 12 in each group.Group A was not treated after establishing spinal cord injury model,group B was given intraperitoneal injection of EPO at 30 minutes after establishing spinal cord injury model,and group C was injected with 10μL Ngb-modified BMSCs suspension immediately after model establishment of spinal cord injury model and EPO was intraperitoneally injected 30 minutes after model establishment.Statistical analysis of Basso-Beattie-Bresnahan(BBB),apoptosis rate of spinal cord cells,and the serum levels of tumor necrosis factor(TNF),interleukin(IL)6 and malondialdehyde(MDA)in spinal cord tissues was carried out at 3 days after modeling.Results The BBB scores(5.33±0.77 points,6.72±0.81 points)of the group C at 3days and 7days after modeling were significantly higher than those of group B and group A(5.18±0.80 points,5.87±0.82 points and 4.09±0.77 points,5.47±0.89,P<0.05).The score at 7 days after model establishment in group B was significantly higher than that of group A(P<0.05).The apoptosis rates of spinal cord tissue in group C were significantly higher than those in group B and group A at 3 days and 7 days after model establishment(P<0.05),and the differences between group B and group A were statistically significant at 7 days after model establishment(P<0.05).The expression levels of serum TNF-α,IL-6 and MDA in spinal cord tissue of group B and group C were significantly lower than those of group A at 3 days and 7 days(P<0.05),and the expression level of MDA in group C was significantly lower than that of group B at 7 days after model establishment(P<0.05).Conclusion The application of Ngb-modified BMSCs in the treatment of acute spinal cord injury in rats can inhibit the expression of inflammatory cytokines and lipid peroxidation,inhibit cell apoptosis,and promote the recovery of nerve function.