Congratulations to Michelle Olsen, she was awarded a $1.6 million grant from the National Institute of Neurological Disorders and Stroke, part of the National Institutes of Health. She is planning to continue studying how astrocyte cells function contributes to brain function. She hopes her work will one day allow scientists to more deeply understand how this cell develops and functions in the healthy brain so that they can better treat neurodevelopmental disorders and neurological disease

Astrocytes appear, or are born, late in the third trimester of fetal development, well after their more well-studied neighbors, the neurons. Astrocytes produce long tentacles or cell processes that appear to wrap around many points of contact, or synapses, between neurons, protecting and stabilizing these vital connections. But so far scientists know little about what “recruits” these astrocytic processes to neuronal synapses.

Yet, Olsen and her lab may have identified an important molecular player in that process. Scientists have long known that neurons release at the synapse a protein, “brain-derived neurotrophic factor” or BDNF, to aid in neuron-to-neuron communication, growth and function. Astrocytes produce the protein TrkB — that’s short for Tropomyosin receptor kinase B — a receptor for BDNF. Olsen suspects this BDNF/TrkB pathway facilitates neuron-to-astrocyte communication — a disruption of which could alter the development of astrocytes and, ultimately, the brain itself.

“We may have been missing a good part of the story by focusing on this pathway only in neurons,” she said. “It may turn out that this signaling pathway, which is critical for early brain development, is just as important in astrocytes. You can imagine if the cells do not develop properly then they don’t ever really normalize.”

The research is much too new to even hypothesize about potential medical benefits, Olsen added: “This is very basic science, really just trying to understand how the brain works normally. How does the astrocyte know where it needs to go?”

Beatriz Torres, a neuroscience doctoral student who works in Olsen’s lab, added, “I am very excited about the grant and the projects that it has outlined. Not very much is known about what actually draws an astrocyte process to a synapse in the first place. Understanding what these cues are could offer us novel therapeutic targets for neurodevelopmental and neuropsychiatric disorders.” 

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