Foley Lisa S, Fullerton David A, Mares Joshua, Sungelo Mitchell, Weyant Michael J, Cleveland Joseph C, Reece T Brett
Department of Surgery, Division of Cardiothoracic Surgery, University of Colorado Denver, Aurora, Colorado.
Department of Surgery, Division of Cardiothoracic Surgery, University of Colorado Denver, Aurora, Colorado.
Ann Thorac Surg. 2017 Dec;104(6):1909-1914. doi: 10.1016/j.athoracsur.2017.07.052. Epub 2017 Oct 31.
Paraplegia from spinal cord ischemia-reperfusion (SCIR) remains an elusive and devastating complication of complex aortic operations. Erythropoietin (EPO) attenuates this injury in models of SCIR. Upregulation of the EPO beta common receptor (βcR) is associated with reduced damage in models of neural injury. The purpose of this study was to examine whether EPO-mediated neuroprotection was dependent on βcR expression. We hypothesized that spinal cord neurons subjected to oxygen-glucose deprivation would mimic SCIR injury in aortic surgery and EPO treatment attenuates this injury in a βcR-dependent fashion.
Lentiviral vectors with βcR knockdown sequences were tested on neuron cell cultures. The virus with greatest βcR knockdown was selected. Spinal cord neurons from perinatal wild-type mice were harvested and cultured to maturity. They were treated with knockdown or nonsense virus and transduced cells were selected. Three groups (βcR knockdown virus, nonsense control virus, no virus control; n = 8 each) were subjected to 1 hour of oxygen-glucose deprivation. Viability was assessed. βcR expression was quantified by immunoblot.
EPO preserved neuronal viability after oxygen-glucose deprivation (0.82 ± 0.04 versus 0.61 ± 0.01; p < 0.01). Additionally, EPO-mediated neuron preservation was similar in the nonsense virus and control mice (0.82 ± 0.04 versus 0.80 ± 0.05; p = 0.77). EPO neuron preservation was lost in βcR knockdown mice compared with nonsense control mice (0.46 ± 0.03 versus 0.80 ± 0.05; p < 0.01).
EPO attenuates neuronal loss after oxygen-glucose deprivation in a βcR-dependent fashion. This receptor holds immense clinical promise as a target for pharmacotherapies treating spinal cord ischemic injury.
脊髓缺血再灌注（SCIR）导致的截瘫仍然是复杂主动脉手术中难以捉摸且具有毁灭性的并发症。促红细胞生成素（EPO）在SCIR模型中可减轻这种损伤。EPOβ共同受体（βcR）的上调与神经损伤模型中损伤的减轻有关。本研究的目的是检验EPO介导的神经保护是否依赖于βcR的表达。我们假设，经历氧糖剥夺的脊髓神经元会模拟主动脉手术中的SCIR损伤，且EPO治疗以βcR依赖的方式减轻这种损伤。
在神经元细胞培养物上测试携带βcR敲低序列的慢病毒载体。选择βcR敲低效果最佳的病毒。从围产期野生型小鼠中获取脊髓神经元并培养至成熟。用敲低病毒或无义病毒处理它们，并筛选转导的细胞。三组（βcR敲低病毒组、无义对照病毒组、无病毒对照组；每组n = 8）经历1小时的氧糖剥夺。评估细胞活力。通过免疫印迹定量βcR的表达。
氧糖剥夺后，EPO可保持神经元活力（0.82±0.04对0.61±0.01；p<0.01）。此外，在无义病毒组小鼠和对照组小鼠中，EPO介导对神经元的保护作用相似（0.82±0.04对0.80±0.05；p = 0.77）。与无义对照小鼠相比，βcR敲低小鼠中EPO对神经元的保护作用消失（0.46±0.03对0.80±0.05；p<）。
EPO以βcR依赖的方式减轻氧糖剥夺后的神经元损失。作为治疗脊髓缺血性损伤的药物治疗靶点，该受体具有巨大的临床应用前景。
