运动皮层和脊髓神经调节促进颈髓挫伤性脊髓损伤后皮质脊髓束轴突生长和运动恢复。
Motor cortex and spinal cord neuromodulation promote corticospinal tract axonal outgrowth and motor recovery after cervical contusion spinal cord injury.
作者信息
Zareen N, Shinozaki M, Ryan D, Alexander H, Amer A, Truong D Q, Khadka N, Sarkar A, Naeem S, Bikson M, Martin J H
机构信息
Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA.
Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA; CUNY Graduate Center, New York, NY 10031, USA.
出版信息
Exp Neurol. 2017 Nov;297:179-189. doi: 10.1016/j.expneurol.2017.08.004. Epub 2017 Aug 10.
Cervical injuries are the most common form of SCI. In this study, we used a neuromodulatory approach to promote skilled movement recovery and repair of the corticospinal tract (CST) after a moderately severe C4 midline contusion in adult rats. We used bilateral epidural intermittent theta burst (iTBS) electrical stimulation of motor cortex to promote CST axonal sprouting and cathodal trans-spinal direct current stimulation (tsDCS) to enhance spinal cord activation to motor cortex stimulation after injury. We used Finite Element Method (FEM) modeling to direct tsDCS to the cervical enlargement. Combined iTBS-tsDCS was delivered for 30min daily for 10days. We compared the effect of stimulation on performance in the horizontal ladder and the Irvine Beattie and Bresnahan forepaw manipulation tasks and CST axonal sprouting in injury-only and injury+stimulation animals. The contusion eliminated the dorsal CST in all animals. tsDCS significantly enhanced motor cortex evoked responses after C4 injury. Using this combined spinal-M1 neuromodulatory approach, we found significant recovery of skilled locomotion and forepaw manipulation skills compared with injury-only controls. The spared CST axons caudal to the lesion in both animal groups derived mostly from lateral CST axons that populated the contralateral intermediate zone. Stimulation enhanced injury-dependent CST axonal outgrowth below and above the level of the injury. This dual neuromodulatory approach produced partial recovery of skilled motor behaviors that normally require integration of posture, upper limb sensory information, and intent for performance. We propose that the motor systems use these new CST projections to control movements better after injury.
颈部损伤是脊髓损伤最常见的形式。在本研究中,我们采用神经调节方法促进成年大鼠中度严重C4中线挫伤后皮质脊髓束(CST)的熟练运动恢复和修复。我们采用双侧硬膜外间歇性θ波爆发(iTBS)电刺激运动皮层以促进CST轴突发芽,并采用阴极经脊髓直流电刺激(tsDCS)增强损伤后脊髓对运动皮层刺激的激活。我们使用有限元方法(FEM)建模将tsDCS引导至颈膨大。联合iTBS-tsDCS每天进行30分钟,共10天。我们比较了刺激对水平阶梯试验、欧文·比蒂和布雷斯纳汉前爪操作任务的表现以及仅损伤组和损伤+刺激组动物中CST轴突发芽的影响。挫伤消除了所有动物的背侧CST。tsDCS显著增强了C4损伤后运动皮层诱发反应。使用这种联合脊髓-运动皮层1区神经调节方法,我们发现与仅损伤对照组相比,熟练运动和前爪操作技能有显著恢复。两组动物损伤部位尾侧保留的CST轴突大多来自位于对侧中间带的外侧CST轴突。刺激增强了损伤水平以下和以上损伤依赖性CST轴突的生长。这种双重神经调节方法使通常需要整合姿势、上肢感觉信息和执行意图的熟练运动行为部分恢复。我们提出运动系统利用这些新的CST投射在损伤后更好地控制运动。