Glial cells, which help neurons communicate with each other, can leave the central nervous system and cross into the peripheral nervous system to compensate for missing cells, according to new research in the Dec. 2 issue of The Journal of Neuroscience.
The animal study contributes to researchers' basic understanding of how the two nervous systems develop and are maintained, which is essential for the effective treatment of diseases such as multiple sclerosis.
The nervous system is divided into the central nervous system (the brain and spinal cord) and the peripheral nervous system (sensory organs, muscles, and glands). A major difference between the systems is that each has its own type of glial cells. In a healthy body, glial cells are tightly segregated and aren't known to travel between the two systems. The peripheral nervous system also regenerates more than the central nervous system, due in part to its glial cells — a characteristic that, if better understood, might be used to improve the regenerative capabilities of the central nervous system.
Glial cells serve nerve cells by insulating them with layers of fats and proteins called myelin. Myelin coatings are necessary for nerve signals to be transmitted normally; when the sheaths are lost, disorders involving impairment in sensation, movement and cognition such as multiple sclerosis or amyotrophic lateral sclerosis develop. Glial cells named oligodendrocytes produce myelin around nerves of the central nervous system, while those named Schwann cells make myelin that insulates peripheral nerves.
This study shows that in the absence of Schwann cells, oligodendrocytes migrate from the central nervous system along motor nerves and form myelin on peripheral nerves, indicating that glial cell movement across the border is controlled by a self-policing mechanism.
"Past studies have hinted that Schwann cells can cross into the central nervous system after peripheral nerves near the border are damaged, or after central nerves lose their myelin sheath," said Bruce Appel, PhD, of the University of Colorado Denver Anschutz Medical Campus, one of the study's authors. "However, migration across the border has never been observed directly, nor was there any evidence that oligodendrocytes can move in the opposite direction."
The authors used time-lapse video of mutant zebrafish to study the glial cell movement. Movies of translucent live zebrafish that lacked Schwann cells showed that oligodendrocytes left the central nervous system to wrap peripheral nerves with myelin — effectively attempting to compensate for the missing Schwann cells.
"This new observation is not only relevant to normal nerve function, but also to potential causes of disease in the peripheral nervous system. We're still unsure as to exactly how foreign glial cells interact with the other system. Do they help heal or do they act as a toxin?" said Bruce Trapp, PhD, at the Cleveland Clinic, who is unaffiliated with the study. "Knowing the mechanisms that anatomically restrict peripheral and central nervous system glia could help develop therapies that treat or prevent certain nervous system diseases."
Appel and his colleagues said that future investigations are needed to determine how different glial cells communicate to restrict their movements between nervous systems, and whether oligodendrocyte myelin can fully substitute for Schwann cell myelin on motor nerves.
Study video and images are available upon request.
The research was supported by the National Institute of Neurological Disorders and Stroke and a zebrafish initiative funded by the Vanderbilt University Academic Venture Capital Fund.
The Journal of Neuroscience is published by the Society for Neuroscience, an organization of more than 40,000 basic scientists and clinicians who study the brain and nervous system. Appel can be reached at firstname.lastname@example.org.
Kat Snodgrass | EurekAlert!
Mitochondria control stem cell fate
27.10.2016 | Technische Universität München
How a fungus inhibits the immune system of plants
27.10.2016 | Julius-Maximilians-Universität Würzburg
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
27.10.2016 | Life Sciences
27.10.2016 | Life Sciences
26.10.2016 | Power and Electrical Engineering