Myelin Plasticity and Behaviour - Connecting the Dots

2017 | PMID: 29054040 | DOI: 10.1016/j.conb.2017.09.014

ABSTRACT:

“Myelin sheaths in the vertebrate nervous system enable faster impulse propagation, while myelinating glia provide vital support to axons. Once considered a static insulator, converging evidence now suggests that myelin in the central nervous system can be dynamically regulated by neuronal activity and continues to participate in nervous system plasticity beyond development. While the link between experience and myelination gains increased recognition, it is still unclear what role such adaptive myelination plays in facilitating and shaping behaviour.”

“In this review, we will discuss new insights into the link between myelin plasticity and behaviour, as well as mechanistic aspects of myelin remodeling that may help to elucidate this intriguing process.”

Evidence for Myelin Sheath Remodeling Revealed by In Vivo Imaging

2018 | PMID: 29429620 | DOI: 10.1016/j.cub.2018.01.017

Emerging Cellular and Molecular Strategies for Enhancing Central Nervous System (CNS) Remyelination

2018 | PMID: 29914096 | DOI: 10.3390/brainsci8060111

ABSTRACT:

“Myelination is critical for the normal functioning of the central nervous system (CNS) in vertebrates. Conditions in which the development of myelin is perturbed result in severely compromised individuals often with shorter lifespans, while loss of myelin in the adult results in a variety of functional deficits.”

“Several lines of evidence suggest it is feasible to develop strategies that enhance the capacity of the CNS to undergo remyelination and potentially reverse functional deficits. Such strategies include cellular therapies using either neural or mesenchymal stem cells as well as molecular regulators of oligodendrocyte development and differentiation. Given the prevalence of demyelinating diseases and their effects on the quality of life for affected individuals it is imperative that effective therapies are developed. Here we discuss some of the new approaches to CNS myelin repair that hold promise for reducing the burden of diseases characterized by myelin loss.”

Thin Myelin Sheaths as the Hallmark of Remyelination Persist Over Time and Preserve Axon Function

2017 | PMID: 29078396 | DOI: 10.1073/pnas.1714183114

Extensive Remyelination of the CNS Leads to Functional Recovery

2009 | PMID: 19342494 | DOI: 10.1073/pnas.0812500106

“Remyelination of the CNS in multiple sclerosis is thought to be important to restore conduction and protect axons against degeneration. Yet the role that remyelination plays in clinical recovery of function remains unproven. Here, we show that cats fed an irradiated diet during gestation developed a severe neurologic disease resulting from extensive myelin vacuolation and subsequent demyelination. Despite the severe myelin degeneration, axons remained essentially intact. There was a prompt endogenous response by cells of the oligodendrocyte lineage to the demyelination, with remyelination occurring simultaneously. Cats that were returned to a normal diet recovered slowly so that by 3–4 months they were neurologically normal. Histological examination of the CNS at this point showed extensive remyelination that was especially notable in the optic nerve where almost the entire nerve was remyelinated. Biochemical analysis of the diet and tissues from affected cats showed no dietary deficiencies or toxic accumulations. Thus, although the etiology of this remarkable disease remains unknown, it shows unequivocally that where axons are preserved remyelination is the default pathway in the CNS in nonimmune-mediated demyelinating disease. Most importantly, it confirms the clinical relevance of remyelination and its ability to restore function.”