Remodelling of myelinated axons and oligodendrocyte differentiation is stimulated by environmental enrichment in the young adult brain
journal contributionposted on 2023-05-21, 16:29 authored by Nicholson, M, Wood, RJ, Gonsalvez, DG, Hannan, AJ, Jessica FletcherJessica Fletcher, Xiao, J, Murray, SS
Oligodendrocyte production and myelination continues lifelong in the central nervous system (CNS), and all stages of this process can be adaptively regulated by neuronal activity. While artificial exogenous stimulation of neuronal circuits greatly enhances oligodendrocyte progenitor cell (OPC) production and increases myelination during development, the extent to which physiological stimuli replicates this is unclear, particularly in the adult CNS when the rate of new myelin addition slows. Here, we used environmental enrichment (EE) to physiologically stimulate neuronal activity for 6 weeks in 9-week-old C57BL/six male and female mice and found no increase in compact myelin in the corpus callosum or somatosensory cortex. Instead, we observed a global increase in callosal axon diameter with thicker myelin sheaths, elongated paranodes and shortened nodes of Ranvier. These findings indicate that EE induced the dynamic structural remodelling of myelinated axons. Additionally, we observed a global increase in the differentiation of OPCs and pre-myelinating oligodendroglia in the corpus callosum and somatosensory cortex. Our findings of structural remodelling of myelinated axons in response to physiological neural stimuli during young adulthood provide important insights in understanding experience-dependent myelin plasticity throughout the lifespan and provide a platform to investigate axon-myelin interactions in a physiologically relevant context.
Publication titleEuropean Journal of Neuroscience
Department/SchoolMenzies Institute for Medical Research
PublisherBlackwell Publishing Ltd
Place of publication9600 Garsington Rd, Oxford, England, Oxon, Ox4 2Dg
Rights statement© 2022 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd. This article is an open access article under the terms and conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/) which permits use, distribution and reproduction in any medium, provided the original work is properly cited.