Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland.
SPPIN - Saints-Pères Paris Institute for the Neurosciences, CNRS, Université de Paris, Paris, France.
Adv Neurobiol. 2022;28:375-394. doi: 10.1007/978-3-031-07167-6_15.
Spinal alpha-motoneurons are classified in several types depending on the contractile properties of the innervated muscle fibers. This diversity is further displayed in different levels of vulnerability of distinct motor units to neurodegenerative diseases such as Amyotrophic Lateral Sclerosis (ALS). We summarize recent data suggesting that, contrary to the excitotoxicity hypothesis, the most vulnerable motor units are hypoexcitable and experience a reduction in their firing prior to symptoms onset in ALS. We suggest that a dysregulation of activity-dependent transcriptional programs in these motoneurons alter crucial cellular functions such as mitochondrial biogenesis, autophagy, axonal sprouting capability and re-innervation of neuromuscular junctions.
脊髓α运动神经元根据其支配的肌纤维的收缩特性可分为几种类型。这种多样性在不同运动单位对神经退行性疾病（如肌萎缩侧索硬化症（ALS））的易感性方面表现得更为明显。我们总结了最近的数据，表明与兴奋性毒性假说相反，最易受损的运动单位兴奋性较低，并在 ALS 症状出现前其放电活动减少。我们认为，这些运动神经元中活性依赖性转录程序的失调改变了关键的细胞功能，如线粒体生物发生、自噬、轴突发芽能力和神经肌肉接头的再支配。
