A type of brain cell that can self-renew is regulated by circadian rhythms, providing important insights into how the body’s internal clock may promote healing after traumatic brain injury (TBI), according to new research from Children’s National Hospital.
Released in the last issue of eNeuro, the findings open new avenues of research for future TBI therapies. These injuries are currently managed only with supportive care and rehabilitation, rather than targeted drug treatment options. The findings also underscore the importance of addressing circadian disorders to help heal injured brains.
Many of the body’s cells follow a 24-hour rhythm controlled by their genes known as the circadian clock. The Children’s National research team found that a relatively newly discovered type of brain cell — known as NG2 glia or oligodendrocyte precursor cells — also follows a circadian rhythm. This cell type is one of the few that continuously renews itself during adulthood and is particularly proliferative in the first week after brain injury.
We found evidence for the role of this well-known molecular pathway – the molecular circadian clock – in regulating the ability of these NG2 glia to proliferate, both at rest and after injury. This will serve as a starting point to further explore avenues to control cellular regeneration and optimize recovery from injury.”
Terry Dean, MD, Ph.D., intensive care specialist at Children’s National and lead author of the paper
Sometimes referred to as “the silent epidemic,” TBI affects an estimated 69 million people worldwide each year, with injuries ranging from minor concussions to serious injuries causing death or lifelong disability. In the United States alone, approximately 2.8 million people contract TBI each year, including 630,000 children. TBI is the leading cause of death in people under the age of 45, and those who survive are often left with persistent physical, cognitive and psychological disabilities.
Yet targeted therapies for TBI do not exist, raising a critical need to uncover the mechanisms that could unlock the regeneration of these NG2 glial cells, the most abundant type of brain cell known to proliferate and self-regulate. renew in adult brain.
“It is essential for researchers to know that cell turnover is coordinated with the time of day,” said Vittorio Gallo, Ph.D., interim chief academic officer and interim director of the Children’s National Research Institute. “With this knowledge, we can dig deeper into the body’s genetic healing process to understand how cells regulate and regenerate themselves.”
National Children’s Hospital
dean, T., et al. (2022) Endogenous circadian clock machines in cortical NG2 glia regulate cellular proliferation. eNeuro. doi.org/10.1523/ENEURO.0110-22.2022.