Department of Motor Function Analysis, Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Shogoin, Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.
Sci Rep. 2024 Aug 16;14(1):19016. doi: 10.1038/s41598-024-69251-4.
Peripheral nerve injury (PNI) often leads to retrograde cell death in the spinal cord and dorsal root ganglia (DRG), hindering nerve regeneration and functional recovery. Repetitive magnetic stimulation (rMS) promotes nerve regeneration following PNI. Therefore, this study aimed to investigate the effects of rMS on post-injury neuronal death and nerve regeneration. Seventy-two rats underwent autologous sciatic nerve grafting and were divided into two groups: the rMS group, which received rMS and the control (CON) group, which received no treatment. Motor neuron, DRG neuron, and caspase-3 positive DRG neuron counts, as well as DRG mRNA expression analyses, were conducted at 1-, 4-, and 8-weeks post-injury. Functional and axon regeneration analyses were performed at 8-weeks post-injury. The CON group demonstrated a decreased DRG neuron count starting from 1 week post-injury, whereas the rMS group exhibited significantly higher DRG neuron counts at 1- and 4-weeks post-injury. At 8-weeks post-injury, the rMS group demonstrated a significantly greater myelinated nerve fiber density in autografted nerves. Furthermore, functional analysis showed significant improvements in latency and toe angle in the rMS group. Overall, these results suggest that rMS can prevent DRG neuron death and enhance nerve regeneration and motor function recovery after PNI.
周围神经损伤（PNI）常导致脊髓和背根神经节（DRG）中的逆行性细胞死亡，阻碍神经再生和功能恢复。重复磁刺激（rMS）可促进 PNI 后的神经再生。因此，本研究旨在探讨 rMS 对损伤后神经元死亡和神经再生的影响。72 只大鼠进行自体坐骨神经移植，并分为 rMS 组和对照组（CON），rMS 组接受 rMS，CON 组未接受治疗。在损伤后 1、4 和 8 周进行运动神经元、DRG 神经元和 caspase-3 阳性 DRG 神经元计数以及 DRG mRNA 表达分析。在损伤后 8 周进行功能和轴突再生分析。CON 组从损伤后 1 周开始 DRG 神经元计数减少，而 rMS 组在损伤后 1 周和 4 周时 DRG 神经元计数显著升高。在损伤后 8 周时，rMS 组在自体移植神经中表现出更高的有髓神经纤维密度。此外，功能分析显示 rMS 组在潜伏期和趾角方面有显著改善。综上所述，这些结果表明 rMS 可预防 DRG 神经元死亡，并增强 PNI 后神经再生和运动功能恢复。
