Ye Hui, Chen Yanan, Chen Ji, Hendee Jenna
Department of Biology, Loyola University Chicago, Chicago, IL, United States of America.
Department of Electrical and Computer Engineering, University of Houston, Houston, TX, United States of America.
J Neural Eng. 2025 Feb 14;22(1):016042. doi: 10.1088/1741-2552/adb213.
. Axonal demyelination leads to failure of axonal conduction. Current research on demyelination focuses on the promotion of remyelination. Electromagnetic stimulation is widely used to promote neural activity. We hypothesized that electromagnetic stimulation of the demyelinated area, by providing excitation to the nodes of Ranvier, could rescue locally demyelinated axons from conductance failure.. We built a multi-compartment NEURON model of a myelinated axon under electromagnetic stimulation. We simulated the action potential (AP) propagation and observed conductance failure when local demyelination occurred. Conductance failure was due to current leakage and a lack of activation of the nodes in the demyelinated region. To investigate the effects of electromagnetic stimulation on locally demyelinated axons, we positioned a miniature coil next to the affected area to activate nodes in the demyelinated region.. Subthreshold microcoil stimulation caused depolarization of node membranes. This depolarization, in combination with membrane depolarization induced by the invading AP, resulted in sufficient activation of nodes in the demyelinated region and restoration of axonal conductance. Efficacy of restoration was dependent on the amplitude and frequency of the stimuli, and the location of the microcoil relative to the targeted nodes. The restored axonal conductance was due to the enhanced Nacurrent and reduced Kcurrent in the nodes, rather than a reduction in leakage current in the demyelinated region. Finally, we found that microcoil stimulation had no effect on axonal conductance in healthy, myelinated axons.. Activation of nodes in the demyelinated region using electromagnetic stimulation provides an alternative treatment strategy to restore axonal function under local demyelination conditions. Results provide insights to the development of microcoil technology for the treatment of focal segmental demyelination cases, such as neuropraxia, spinal cord injury, and auditory nerve demyelination.
轴突脱髓鞘会导致轴突传导失败。目前关于脱髓鞘的研究主要集中在促进髓鞘再生上。电磁刺激被广泛用于促进神经活动。我们假设,通过对郎飞结提供刺激,对脱髓鞘区域进行电磁刺激可以挽救局部脱髓鞘的轴突,使其免于传导失败。我们构建了一个在电磁刺激下有髓轴突的多房室神经元模型。我们模拟了动作电位(AP)的传播,并观察到局部脱髓鞘发生时的传导失败。传导失败是由于电流泄漏和脱髓鞘区域的节点缺乏激活。为了研究电磁刺激对局部脱髓鞘轴突的影响,我们在受影响区域旁边放置了一个微型线圈,以激活脱髓鞘区域的节点。阈下微线圈刺激导致节点膜去极化。这种去极化,与入侵的动作电位诱导的膜去极化相结合,导致脱髓鞘区域的节点充分激活,并恢复轴突传导。恢复的效果取决于刺激的幅度和频率,以及微线圈相对于目标节点的位置。恢复的轴突传导是由于节点中增强的钠电流和减少的钾电流,而不是脱髓鞘区域泄漏电流的减少。最后,我们发现微线圈刺激对健康的有髓轴突的轴突传导没有影响。使用电磁刺激激活脱髓鞘区域的节点为在局部脱髓鞘条件下恢复轴突功能提供了一种替代治疗策略。研究结果为开发用于治疗局灶性节段性脱髓鞘病例(如神经失用症、脊髓损伤和听神经脱髓鞘)的微线圈技术提供了见解。
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J Gen Physiol. 1990-5
Brain Res. 1993-8-13
J Physiol. 1972-12
Neurology. 1978-9
Electromyogr Clin Neurophysiol. 2004
J Physiol. 1972-12
Adv Sci (Weinh). 2024-12
Biomed Phys Eng Express. 2024-4-12
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