Nearly half of brain cells have new function

Researchers at Tufts University School of Medicine have discovered a previously unknown function performed by a type of cell that makes up almost half of all cells in the brain

A new function of astrocytes discovered in mice opens up a whole new direction for neuroscience research that could one day lead to treatments for everything from epilepsy to Alzheimer's to traumatic brain injury, scientists say methods of many diseases

This comes down to how astrocytes interact with neurons, the basic cells of the brain and nervous system that receive input from the outside world

Until now, scientists thought astrocytes were important but had few members in this activity

But until now, they didn't seem to be as electrically active as all-important neurons

"The electrical activity of astrocytes alters the function of neurons," said Chris Dulla, associate professor of neuroscience in the School of Medicine and Graduate School of Biomedical Sciences, in a paper published today in the journal Nature Neuroscience .

In addition to Dulla and first author Moritz Armbruster, other authors of the study include Saptarnab Naskar, Mary Sommer, Elliot Kim, and Philip G.

To make this discovery, the team used entirely new techniques, devising a technique that allowed them to see and study the electrical properties of brain cell interactions that were previously unobservable

"With these new tools, we've basically uncovered entirely new aspects of biology," said Armbruster, assistant professor of neuroscience research in the School of Medicine

"This new technology uses light to image electrical activity," Dulla explained.

Dulla describes astrocytes as "making sure everything is good in the brain, and if something's not right, if there's an injury or a viral infection, they detect it, try to respond, and then try to protect the brain from damage

Neuron-to-neuron communication occurs by releasing chemicals called neurotransmitters

"So neurons control the behavior of astrocytes, and they communicate back and forth

Implications for future research

The discovery of astrocyte-neuron interaction raises many questions about how this interaction plays a role in brain pathology and the development of learning and memory

In Alzheimer's, for example, astrocytes don't control neurotransmitters, even though that's their basic job, Dulla explained

"The accumulation of extracellular potassium in the brain has been hypothesized to contribute to the pathology of epilepsy and migraine," Armbruster said.
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This new study gives us a better understanding of how astrocytes clear this accumulation and help maintain Excited and balanced
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The researchers are now screening existing drugs to see if they can manipulate the interaction of neurons and astrocytes
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"By doing this, can we one day help people learn faster and better? Can we repair brain damage when it happens?" Dulla asked
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The new technology used for this discovery not only opens up new avenues for thinking about astrocyte activity, but also for imaging brain activity
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Until now, there has been no way to image potassium activity in the brain, for example, or to study how potassium is involved in sleep, metabolism, or brain damage and infection
.

He said: "We're making these tools available to other labs so they can use the same analyses and techniques to study the problems they're interested in
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Scientists are gaining access to research headaches, breathing, developmental disorders and a range of different neurological disorders.
tools
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Courtesy of Tufts University