Department of Biology, Faculty of Sciences, University of Zabol, Zabol, Iran.
Cellular and Molecular Research Center, Iran University of Medical Science, P.O. Box 14665-354, Tehran, Iran.
Metab Brain Dis. 2018 Feb;33(1):27-37. doi: 10.1007/s11011-017-0099-9. Epub 2017 Oct 12.
Multiple Sclerosis (MS), is a disease that degenerates myelin in central nervous system (CNS). Reactive oxygen species (ROSs) are toxic metabolites, and accumulating data indicate that ROSs-mediated apoptosis of oligodendrocytes (OLGs) plays a major role in the pathogenesis of MS under oxidative stress conditions. In this study, we investigated the role of endogenous antioxidant alpha-lipoic acid (ALA) as ROSs scavenger in the OLGs loss and myelin degeneration during cuprizone (cup)-induced demyelination in the experimental model of MS. Our results have shown that ALA treatment significantly increased population of mature OLGs (MOG cells), as well as decreased oxidative stress (ROSs, COX-2 and PGE2) and apoptosis mediators (caspase-3 and Bax/Bcl2 ratio) in corpus callosum (CC). Surprisingly, ALA significantly stimulates population of NG2 chondroitin sulfate proteoglycan positive glia (NG2 cells or polydendrocytes), from week 4 afterward. Accordingly ALA could prevents apoptosis, delays demyelination and recruits OLGs survival and regeneration mechanisms in CC. We conclude that ALA has protective effects against toxic demyelination via reduction of redox signaling, and alleviation of polydendrocytes vulnerability to excitotoxic challenge.
多发性硬化症(MS)是一种中枢神经系统(CNS)髓鞘退化的疾病。活性氧(ROS)是有毒的代谢物,越来越多的数据表明,在氧化应激条件下,ROS 介导的少突胶质细胞(OLGs)凋亡在 MS 的发病机制中起主要作用。在这项研究中,我们研究了内源性抗氧化剂α-硫辛酸(ALA)作为 ROS 清除剂在实验性 MS 模型中杯状蛋白(cup)诱导脱髓鞘过程中 OLGs 丢失和髓鞘变性中的作用。我们的结果表明,ALA 治疗可显著增加成熟 OLGs(MOG 细胞)的数量,同时降低氧化应激(ROS、COX-2 和 PGE2)和凋亡介质(caspase-3 和 Bax/Bcl2 比值)在胼胝体(CC)中的表达。令人惊讶的是,从第 4 周开始,ALA 可显著增加 NG2 软骨素硫酸蛋白聚糖阳性胶质细胞(NG2 细胞或多形细胞)的数量。因此,ALA 可防止 CC 中的凋亡、延迟脱髓鞘以及招募 OLGs 存活和再生机制。我们得出结论,ALA 通过减少氧化还原信号和减轻多形细胞对兴奋性挑战的脆弱性,对有毒性脱髓鞘具有保护作用。