Central nervous system

A new University of Virginia study proves that a damaged peripheral nervous system is capable of repairing itself when healthy cells are there from the central nervous system. The finding has implications for the future treatment of debilitating and life-threatening nervous system disorders affecting children; such as muscular dystrophy, Guillain-Barre Syndrome and Charcot-Marie-Tooth Disease.
Oligodendrocytes are a type of cell glia. They are the glue that holds together brain matter and are key components in the development of the central nervous system. These cells also are important to the regeneration or repair of these systems in response to disease or injury. They make myelin, a layer of protein and fatty material that acts like electrical tape to insulate; axons, a threadlike part of nerve cells on which electrical signals transmit in a line from one cell to the next.

Central nervous system

When that sheathing degenerates, such as happens to diseased nerve cells in multiple sclerosis; critical messages from the brain are along the path to other areas of the body, resulting in severe impairment. Oligodendrocytes are highly migratory, but they always end up in the same locations of the central nervous system; even though they actually have the capability to go anywhere.

Using zebrafish as a study model (about 80 % of a zebrafish’s nervous-system genes are the same as in humans); Kucenas and postdoctoral fellow Laura Fontenas that oligodendrocytes are actively to the central nervous system through tight control of neural activity.

“When they disrupt specific mechanisms of neural activity; they find that they can actually get these oligodendrocytes to migrate to portions of the nervous system; where they technically should not go to the periphery and they wanted to know if they can conduct repairs there.

Mechanism of neuronal activity

She and Fontenay identified a compound that perturbs the oligodendrocytes into migration and used zebrafish that were genetically mutated to model such diseases as muscular dystrophy, Guillain-Barre syndrome, and Charcot-Marie-Tooth disease. They disrupted the mechanism of neuronal activity to recruit oligodendrocytes to the peripheral nervous system; that they replace defective myelin that is lost in those disorders.

In ongoing studies in the lab using models of these diseases; Kucenas and Fontana are finding that adult fish with oligodendrocytes in the peripheral nervous system swim; better than mutant adult fish with no oligodendrocytes. This suggests that a new class of drugs could developed to coax oligodendrocytes to migrate to the peripheral nervous system and help it repair itself.

In conclusion, this finding has very real potential to change how they think about approaching the treatment of neurodegenerative diseases. “My hope is that someday our discoveries will help children with impairing neurological diseases to  able to get out of their wheelchairs and live an enhanced quality of life.”