Ahmed Zaghloul, Samaddar Sreyashi, Hassieb May, Sadek Rodina, Morozova Viktoriya, Begum Sultana
Department of Physical Therapy, The College of Staten Island, City University of New York, Staten Island, NY, United States.
Center for Developmental Neuroscience, The College of Staten Island, City University of New York, Staten Island, NY, United States.
Front Neurol. 2025 Jun 26;16:1594169. doi: 10.3389/fneur.2025.1594169. eCollection 2025.
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects motor neurons in the spinal cord and brain. We have developed a novel non-invasive approach, MultiPath-DCS, which utilizes direct current stimulation at multiple sites along the neural axis to provide simultaneous spinal and peripheral stimulation targeted at the affected limbs. MultiPath-DCS modulates the excitability of spinal cord neurons. This effect is significant for ALS, as motor neuron hyperexcitability is a fundamental characteristic of the disease.
This study used a transgenic mouse model of ALS (SOD1-G93A). Anodal-MultiPath-DCS was applied with six electrodes: three on the spine (centered on T13 and with an anodal polarity), two on the sciatic nerves (one on each nerve), and one on the abdomen. Mice were divided into two groups (stimulated vs. unstimulated or sham-stimulated). The stimulated animals received stimulation for one hour a day, three times a week, for three weeks. Survival was calculated from the onset of the disease and birth until the animal's endpoint. We also performed various electrophysiological and molecular experiments to uncover the mechanism of action.
We demonstrated molecular changes induced by anodal MultiPath-DCS, including (a) reduced expression of mutant SOD1 protein, (b) decreased expression of elevated NKCC1, (c) reduced phosphorylated tau, (d) increased expression of HSP70, and (e) increased expression of LC3B. Additionally, we found that treatment with Anodal-MultiPath-DCS (anode on the spinal column) reduces long-term neuronal spinal excitability, slows the progression of muscle weakness, and extends the lifespan of stimulated mice. The mean survival time in the control group was 12.4 days. In comparison, the mean survival time in the stimulated group was 21.6 days using a therapeutic stimulation paradigm, representing a 74% increase in survival from disease onset. Spinal motor neuron survival showed a 54% increase in stimulated compared to non-stimulated groups.
Combined, this data provides evidence that Anodal-MultiPath-DCS reduces hyperexcitability and enhances the clearance of misfolded proteins by modulating autophagy and proteolytic systems. By decreasing spinal excitability and clearing toxic proteins from motor neurons, Anodal-MultiPath-DCS promotes survival and could serve as a disease-modifying intervention for ALS.
肌萎缩侧索硬化症（ALS）是一种进行性神经退行性疾病，会影响脊髓和大脑中的运动神经元。我们开发了一种新型非侵入性方法——多路径直流电刺激（MultiPath-DCS），该方法利用沿神经轴多个部位的直流电刺激，对受影响肢体同时进行脊髓和外周刺激。多路径直流电刺激可调节脊髓神经元的兴奋性。这种效应对于肌萎缩侧索硬化症具有重要意义，因为运动神经元兴奋性过高是该疾病的一个基本特征。
本研究使用了肌萎缩侧索硬化症的转基因小鼠模型（SOD1-G93A）。阳极多路径直流电刺激通过六个电极施加：三个在脊柱上（以T13为中心，阳极极性），两个在坐骨神经上（每条神经一个），一个在腹部。小鼠分为两组（刺激组与未刺激组或假刺激组）。刺激组动物每天接受一小时刺激，每周三次，共三周。从疾病发作和出生到动物终点计算生存期。我们还进行了各种电生理和分子实验以揭示其作用机制。
我们证明了阳极多路径直流电刺激诱导的分子变化，包括（a）突变型SOD1蛋白表达降低，（b）升高的NKCC1表达减少，（c）磷酸化tau蛋白减少，（d）HSP70表达增加，以及（e）LC3B表达增加。此外，我们发现用阳极多路径直流电刺激（脊柱上的阳极）治疗可降低脊髓神经元的长期兴奋性，减缓肌肉无力的进展，并延长受刺激小鼠的寿命。对照组的平均生存时间为12.4天。相比之下，使用治疗性刺激模式时，刺激组的平均生存时间为21.6天，从疾病发作起生存期增加了74%。与未刺激组相比，刺激组脊髓运动神经元的存活率提高了54%。
综合来看，这些数据表明阳极多路径直流电刺激通过调节自噬和蛋白水解系统降低兴奋性并增强错误折叠蛋白的清除。通过降低脊髓兴奋性并从运动神经元中清除有毒蛋白质，阳极多路径直流电刺激促进了存活，并可作为肌萎缩侧索硬化症的疾病修饰干预措施。
