Teo Wulin, Caprariello Andrew V, Morgan Megan L, Luchicchi Antonio, Schenk Geert J, Joseph Jeffrey T, Geurts Jeroen J G, Stys Peter K
Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada.
Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit, Amsterdam Neuroscience, 1081 HZ Amsterdam, The Netherlands.
Proc Natl Acad Sci U S A. 2021 Feb 23;118(8). doi: 10.1073/pnas.2016897118.
The molecular composition of myelin membranes determines their structure and function. Even minute changes to the biochemical balance can have profound consequences for axonal conduction and the synchronicity of neural networks. Hypothesizing that the earliest indication of myelin injury involves changes in the composition and/or polarity of its constituent lipids, we developed a sensitive spectroscopic technique for defining the chemical polarity of myelin lipids in fixed frozen tissue sections from rodent and human. The method uses a simple staining procedure involving the lipophilic dye Nile Red, whose fluorescence spectrum varies according to the chemical polarity of the microenvironment into which the dye embeds. Nile Red spectroscopy identified histologically intact yet biochemically altered myelin in prelesioned tissues, including mouse white matter following subdemyelinating cuprizone intoxication, as well as normal-appearing white matter in multiple sclerosis brain. Nile Red spectroscopy offers a relatively simple yet highly sensitive technique for detecting subtle myelin changes.
髓鞘膜的分子组成决定了它们的结构和功能。即使是生化平衡的微小变化也可能对轴突传导和神经网络的同步性产生深远影响。假设髓鞘损伤的最早迹象涉及其组成脂质的成分和/或极性变化，我们开发了一种灵敏的光谱技术，用于确定来自啮齿动物和人类的固定冷冻组织切片中髓鞘脂质的化学极性。该方法采用一种简单的染色程序，涉及亲脂性染料尼罗红，其荧光光谱会根据染料嵌入的微环境的化学极性而变化。尼罗红光谱法在病变前组织中识别出组织学上完整但生化改变的髓鞘，包括亚脱髓鞘铜螯合剂中毒后的小鼠白质，以及多发性硬化症脑内外观正常的白质。尼罗红光谱法为检测髓鞘的细微变化提供了一种相对简单但高度灵敏的技术。
