Department of Health Sciences and Sport Medicine, Hungarian University of Sports Science, 1123 Budapest, Hungary.
Department of Sports Medicine, Semmelweis University, 1122 Budapest, Hungary.
Cells. 2024 Mar 12;13(6):492. doi: 10.3390/cells13060492.
Amyotrophic lateral sclerosis (ALS) is a mysterious lethal multisystem neurodegenerative disease that gradually leads to the progressive loss of motor neurons. A recent non-contact dying-back injury mechanism theory for ALS proposed that the primary damage is an acquired irreversible intrafusal proprioceptive terminal Piezo2 channelopathy with underlying genetic and environmental risk factors. Underpinning this is the theory that excessively prolonged proprioceptive mechanotransduction under allostasis may induce dysfunctionality in mitochondria, leading to Piezo2 channelopathy. This microinjury is suggested to provide one gateway from physiology to pathophysiology. The chronic, but not irreversible, form of this Piezo2 channelopathy is implicated in many diseases with unknown etiology. Dry eye disease is one of them where replenishing synthetic proteoglycans promote nerve regeneration. Syndecans, especially syndecan-3, are proposed as the first critical link in this hierarchical ordered depletory pathomechanism as proton-collecting/distributing antennas; hence, they may play a role in ALS pathomechanism onset. Even more importantly, the shedding or charge-altering variants of Syndecan-3 may contribute to the Piezo2 channelopathy-induced disruption of the Piezo2-initiated proton-based ultrafast long-range signaling through VGLUT1 and VGLUT2. Thus, these alterations may not only cause disruption to ultrafast signaling to the hippocampus in conscious proprioception, but could disrupt the ultrafast proprioceptive signaling feedback to the motoneurons. Correspondingly, an inert Piezo2-initiated proton-based ultrafast signaled proprioceptive skeletal system is coming to light that is suggested to be progressively lost in ALS. In addition, the lost functional link of the MyoD family of inhibitor proteins, as auxiliary subunits of Piezo2, may not only contribute to the theorized acquired Piezo2 channelopathy, but may explain how these microinjured ion channels evolve to be principal transcription activators.
肌萎缩侧索硬化症（ALS）是一种神秘的致命多系统神经退行性疾病，它会逐渐导致运动神经元的进行性丧失。最近提出的 ALS 非接触性退行性损伤机制理论认为，原发性损伤是一种获得性不可逆转的内收肌本体感受终末 Piezo2 通道病，其潜在的遗传和环境风险因素。这一理论的基础是，在所有ostasis 下，本体感觉机械转化过度延长可能导致线粒体功能障碍，从而导致 Piezo2 通道病。这种微损伤被认为是从生理学到病理生理学的一个途径。这种 Piezo2 通道病的慢性但不可逆形式与许多病因不明的疾病有关。干眼症就是其中之一，补充合成蛋白聚糖可促进神经再生。黏附素，特别是黏附素-3，被提出作为这个分层耗竭病理机制的第一个关键环节，作为质子收集/分配天线；因此，它们可能在 ALS 发病机制中起作用。更重要的是， Syndecan-3 的脱落或电荷改变变体可能会导致 Piezo2 通道病引起的 Piezo2 起始质子超快远程信号的破坏，通过 VGLUT1 和 VGLUT2。因此，这些改变不仅可能导致对意识本体感受中超快信号的破坏，还可能破坏对运动神经元的超快本体感觉反馈。相应地，一种惰性的 Piezo2 起始质子超快信号本体感觉骨骼系统正在显现出来，在 ALS 中被认为是逐渐丧失的。此外，Piezo2 的辅助亚基 MyoD 家族抑制蛋白的功能性丧失连接，不仅可能导致理论上获得性的 Piezo2 通道病，还可能解释这些微损伤的离子通道如何演变为主要的转录激活剂。
