Lee Jae Min, Yoo Myung Chul, Kim Yong Jun, Kim Sung Soo, Yeo Seung Geun
Department of Otorhinolaryngology, Head & Neck Surgery, College of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea.
Department of Physical Medicine & Rehabilitation, College of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea.
Antioxidants (Basel). 2024 May 12;13(5):595. doi: 10.3390/antiox13050595.
Facial nerve injury can cause significant functional impairment, impacting both the peripheral and central nervous systems. The present study evaluated changes in facial motor function, numbers of cholinergic neurons and microglia, and nNOS levels in the facial nucleus of the central nervous system (CNS) following peripheral facial nerve injury. Facial nerve function, as determined by eyeblink and whisker-movement reflexes, was evaluated at baseline and 1, 2, 3, 4, 8, and 12 weeks after inducing facial nerve injury through compression or axotomy. The expression of choline acetyltransferase (ChAT), ionized calcium-binding adaptor molecule 1 (Iba-1), and neuronal nitric oxide synthase (nNOS) in the facial nucleus of the CNS was analyzed 2, 4, and 12 weeks after peripheral facial nerve injury. Compression-induced facial nerve injury was found to lead to temporary facial motor impairment, whereas axotomy resulted in persistent impairment. Moreover, both compression and axotomy reduced ChAT expression and increased Iba-1 and nNOS expression in the facial nucleus, indicating upregulation of an inflammatory response and neurodegeneration. These results indicate that, compared with compression-induced injury, axotomy-induced facial nerve injury results in greater facial motor dysfunction and more persistent microglial and nitric oxide activation in the facial nucleus of the CNS.
面神经损伤可导致严重的功能障碍，影响外周和中枢神经系统。本研究评估了外周面神经损伤后中枢神经系统（CNS）面神经核中面部运动功能、胆碱能神经元和小胶质细胞数量以及nNOS水平的变化。通过压迫或切断术诱导面神经损伤后，在基线以及损伤后1、2、3、4、8和12周，根据眨眼和触须运动反射评估面神经功能。在外周面神经损伤后2、4和12周，分析CNS面神经核中胆碱乙酰转移酶（ChAT）、离子钙结合衔接分子1（Iba-1）和神经元型一氧化氮合酶（nNOS）的表达。发现压迫诱导的面神经损伤导致暂时性面部运动障碍，而切断术导致持续性损伤。此外，压迫和切断术均降低了面神经核中ChAT的表达，并增加了Iba-1和nNOS的表达，表明炎症反应和神经退行性变上调。这些结果表明，与压迫诱导的损伤相比，切断术诱导的面神经损伤导致更严重的面部运动功能障碍，以及CNS面神经核中更持久的小胶质细胞和一氧化氮激活。
