A Unity Health scientist has revealed a new cellular interaction that aids in the regeneration of damaged myelin, the protective layer that coats nerve cells in the central nervous system. The discovery could lead to the development of new drug treatments for Multiple Sclerosis and other neurodegenerative diseases, including Alzheimer’s disease, she says.
The discovery, recently published in the science journal Nature Communications and chosen as an Editor’s Pick, was led by Dr. Veronique Miron, scientist at the Keenan Research Centre for Biomedical Science and John David Eaton Chair in MS research at the BARLO MS Centre.
Miron’s research lab focuses on identifying new treatment strategies for neurological conditions where myelin is damaged.
“MS is a condition that primarily impacts people in the prime of their lives, and Canada has one of the highest rates of MS in the world,” she said. “I’ve always wanted to have a positive impact on patients with this condition through research.”
The surprising role of astrocytes
Miron and her lab discovered that star-shaped cells in the central nervous system called astrocytes play a critical role in repairing myelin. Myelin, a protective layer of protein and fats that wraps around nerve cells, is important because it allows our nerve cells to quickly send and receive electrical signals that control every aspect of our body’s functioning.
Cells in our brain called oligodendrocytes make and repair myelin. But certain diseases and conditions, such as MS, cause oligodendrocytes to die and in turn lead to damage to myelin, slowing down the transmission of our body’s electrical signals. This is what causes the symptoms of MS, which can include loss of vision, loss of function in an arm or leg, spasms and difficulty walking.
Miron’s research team discovered that astrocytes help keep oligodendrocytes alive by supplying them with cholesterol.
The team examined brain tissue from people who had MS, and observed that in lesions where myelin repair had failed, the astrocytes were not making as much cholesterol compared to lesions where myelin repair was occurring. Importantly, in an experimental model, the team discovered they could improve myelin repair by boosting the cholesterol-giving properties of astrocytes with drugs.
“We find this study really exciting because we’ve discovered that astrocytes play a critical role in myelin repair, the pathway they use to lead to this repair of damaged myelin, and also drugs that we may be able to use to target and boost this pathway,” Miron said.
The research team believes the findings will also be important in developing treatments for ageing and Alzheimer’s, where myelin is also damaged.
“We’ve moved along quickly with this one study, and we’re hoping to continue with that kind of acceleration as we work to understand how we can use these drugs to treat MS patients,” Miron said, noting that currently there are no approved treatments aimed at enhancing myelin repair.
“We are working as quickly as we can to translate these findings into meaningful treatments for people with MS.”