In Science essay, Freeman sheds light on star-shaped brain cells
Although glial cells make up the majority of cells in our brain, scientists have only a limited understanding of the most common type: the astrocyte. Large and star-shaped, the astrocyte has recently been the focus of neurobiologists seeking to clarify how such cells are distinguished from others and how they function.
A Nov. 5 Science essay by Marc R. Freeman, PhD, associate professor of neurobiology and a leading expert in the field, details interesting advances made in our understanding of how astrocytes are generated and develop in the brain.
“We do not know the molecular mechanism by which astrocytes are specified, how they grow to assume complex forms and structures, and how they interact with and sculpt developing neural networks,” wrote Dr. Freeman. “Understanding these developmental events in molecular terms will provide insights into the mechanisms by which glia regulate brain development and function, as well as how changes in astrocyte function affect neurological disease.”
Astrocytes have long been known to interact with thousands of synapses and perform a diverse array of functions in the brain, including biochemically supporting the endothelial cells that form the blood-brain barrier, transmitting signals in response to stimulation, providing nutrients to nerve tissue, maintaining the extracellular environment, and repairing the brain and spinal cord following traumatic injuries.
Thanks to recent findings, wrote Freeman, “We have a new appreciation for the fact that astrocytes are far more than simple support cells. They are active participants in the brain assembly and signaling, and it’s abundantly clear that we have only scratched the surface of the depth of their biology.”
One of only 50 young investigators to be named Early Career Scientists by the Howard Hughes Medical Institute last year, Freeman joined UMMS in 2004 and, since then, has focused his research on how glial cells sense brain injury, respond immunologically to neuron death or degeneration, and manage brain recovery from trauma. Understanding the basic roles glial cells perform in these events may prove critical for developing therapies for spinal nerve injuries or neurodegenerative diseases.
To learn more about astrocytes and the future of astrocyte biology, read Freeman’s essay “Specification and Morphogenesisi of Astrocytes” in Science.
