Myelin plasticity in adulthood and aging.
Timothy W Chapman1, Robert A Hill1
1Department of Biological Sciences, Dartmouth College, Hanover, NH, USA.
Neuroscience Letters
|November 26, 2019
Summary
Oligodendrocytes, the cells that form myelin sheaths, exhibit plasticity throughout life. This myelin plasticity may influence brain function and cognitive aging.
Area of Science:
- Neuroscience
- Cell Biology
- Neuroplasticity
Background:
- The central nervous system exhibits lifelong molecular and cellular plasticity, crucial for adapting to stimuli.
- Neuronal structure and synaptic strength changes are primary plasticity mechanisms.
- Emerging evidence indicates myelinating oligodendrocytes also display plasticity in adulthood.
Purpose of the Study:
- To describe forms of myelin plasticity in adult oligodendrocytes.
- To review evidence for myelination changes across the lifespan.
- To explore the link between myelin plasticity defects and cognitive decline in aging.
Main Methods:
- Review of existing literature on oligodendrocyte plasticity.
- Analysis of recent studies demonstrating changes in myelination.
- Discussion of potential mechanisms and implications.
Main Results:
- Oligodendrocytes can generate new cells and modify myelin sheaths (length, thickness, distribution).
- Myelin plasticity occurs throughout life, not just during development.
- Defects in myelin plasticity are potentially linked to age-related cognitive impairment.
Conclusions:
- Myelin plasticity is a significant, yet understudied, aspect of neural adaptability.
- Understanding myelin plasticity offers insights into brain aging and cognitive function.
- Further research is needed to elucidate the dynamic role of myelin in neural circuits and learning.
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