Related Experiment Video
Updated: Dec 15, 2025
08:34
Assessing Microglial Phagocytosis of Myelin Debris in vitro Under Repeated Magnetic Stimulation
Published on: June 17, 2025
786
Microglia phagocytose myelin sheaths to modify developmental myelination
Alexandria N Hughes1, Bruce Appel2
1Neuroscience Graduate Program, University of Colorado, Aurora, CO, USA.
Nature Neuroscience
|July 8, 2020
Summary
Microglia, the brain's immune cells, prune excess myelin sheaths during development. Neuronal activity regulates this myelin pruning by microglia, ensuring proper myelination.
Area of Science:
- Neuroscience
- Developmental Biology
- Cell Biology
Background:
- Oligodendrocytes myelinate neuronal axons during development.
- Excess myelin is produced and eliminated, but the mechanism of myelin elimination is unknown.
- Microglia are known to engulf surplus neurons and synapses.
Purpose of the Study:
- To investigate whether microglia prune myelin sheaths.
- To understand the role of neuronal activity in myelin pruning.
- To determine the consequences of microglial depletion on myelin development.
Main Methods:
- In vivo imaging in zebrafish to visualize microglia-oligodendrocyte-neuron interactions.
- Genetic and chemogenetic manipulation of microglia and neuronal activity.
- Behavioral analysis to assess functional outcomes.
Main Results:
- Microglia were observed to closely associate with oligodendrocytes and phagocytose myelin sheaths.
- Neuronal activity was found to bidirectionally regulate microglial association with neurons and myelin phagocytosis in the optic tectum.
- Microglia depletion led to excessive and ectopic myelin formation.
Conclusions:
- Microglia play a crucial role in pruning excess myelin sheaths during development.
- Neuronal activity regulates microglial myelin pruning, impacting oligodendrocyte targeting.
- This study reveals a novel function for microglia in regulating myelin homeostasis.
Related Concept Videos
01:25Nervous Tissue: Myelin
4.9K
The myelin sheath is a multilayered lipid and protein covering that insulates the axon of a neuron, enhancing the speed of nerve impulse conduction. Axons without this sheath are referred to as unmyelinated. Two types of neuroglia, Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS) are responsible for producing myelin sheaths.
Schwann cells begin to form myelin sheaths around axons during fetal development. They wrap around a small...
Schwann cells begin to form myelin sheaths around axons during fetal development. They wrap around a small...
4.9K
01:15Neurogenesis and Regeneration of Nervous Tissue
1.4K
In the CNS, neurogenesis, the birth of new neurons from stem cells, is limited to the hippocampus in adults. In other regions of the brain and spinal cord, neurogenesis is almost non-existent due to inhibitory influences from neuroglia, especially oligodendrocytes, and the absence of growth-stimulating cues. The myelin produced by oligodendrocytes in the CNS inhibits neuronal regeneration. Furthermore, astrocytes proliferate rapidly after neuronal damage, forming scar tissue that physically...
1.4K
01:04Glial Cells
92.6K
Overview
92.6K
01:31Nervous Tissue: Glial Cells
6.1K
Glia, or neuroglia, are vital support cells that assist neurons in their functions. The term "glia" originates from the Greek word for "glue," reflecting their role in holding the nervous system together. These cells can be categorized into six types: four in the central nervous system (CNS) and two in the peripheral nervous system (PNS).
The CNS glial cell includes the astrocytes, the oligodendrocytes, the microglia, and the ependymal cells.
Astrocytes are star-shaped glial...
The CNS glial cell includes the astrocytes, the oligodendrocytes, the microglia, and the ependymal cells.
Astrocytes are star-shaped glial...
6.1K