Researchers at Tufts University School of Medicine have discovered a previously unknown function performed by a cell type comprising half of all brain cells.
Scientists say the discovery of a new function of cells known as astrocytes in rats would open up a whole new direction for neuroscience research that could one day treat a wide range of disorders, from epilepsy to Alzheimer’s to brain injury.
It goes down to how astrocytes interact with neurons, which receive input from the outer world of brain stem cells and the nervous system. Through a complex set of electrical and chemical signaling, neurons transmit information to different parts of the brain and between the brain and the rest of the nervous system.
Until now, scientists have believed that astrocytes are important, but there are fewer cast members in this activity. Astrocytes guide the growth of axons, long, slender projections of neurons that conduct electrical impulses. They also control neurotransmitters, chemicals that enable the transmission of electrical signals throughout the brain and nervous system. In addition, astrocytes form a blood-brain barrier and respond to injury.
But they didn’t look as electrically active as all-important neurons आता until now.
“The electrical activity of astrocytes alters the functioning of neurons,” says Chris Dulla, an associate professor of neuroscience at the School of Medicine and the Graduate School of Biomedical Sciences and author of a paper published today by Nature Neuroscience.
We have discovered a new way for two important cells in the brain to communicate with each other. Since so much is unknown about how the brain works, finding new basic mechanisms that control brain function is key to developing new treatments for neurological diseases. “
In addition to Dulla and lead author Moritz Armbrester, other authors of the study include Saptarnab Naskar, Mary Somer, Elliott Kim, and Philip G. from Tufts University School of Medicine. Including Hayden; Jacqueline P. from the Cell, Molecular and Developmental Biology program at Tufts Graduate School of Biomedical Sciences. Garcia; And researchers from other institutions.
To make the discovery, the team developed a technique using new technology that enables them to observe and study the electrical properties of the interaction of brain cells, which could not be seen before.
“With these new tools, we’ve discovered completely new aspects of biology,” says Armbraster, an assistant professor of research in neuroscience at the School of Medicine. “As better devices come along — for example, new fluorescent sensors are constantly being developed आम्हाला we will have a better understanding of things we never thought possible before.”
“The new technology gives the image of electrical activity with light,” Dulla explains. “Neurons are very electrically active, and new technology allows us to see if astrocytes are electrically active.”
Dulla describes astrocytes as “making sure that everything in the brain is copecetic, and if something goes wrong, injury or viral infection, they recognize it, try to respond and then try to save the brain from humiliation. Astrocytes What we need to do next is to determine how they change.
Neuron-to-neuron communication occurs through the release of packets of chemicals called neurotransmitters. Scientists know that astrocytes regulate neurotransmitters, helping to ensure that neurons remain healthy and active. But new studies have shown that neurons also release potassium ions, which alter the electrical activity of astrocytes and how they regulate neurotransmitters.
“So the neuron is controlling what the astrocytes are doing and they are communicating back and forth. Neurons and astrocytes talk to each other in a way they didn’t know before, “he says.
Impact on future research
The discovery of the astrocyte-neuron crossstock raises a number of questions about how interactions work in brain pathology and in learning and memory development. “This prompts us to rethink everything about astrocytes, and how the fact that astrocytes are electrically active may affect a wide range of neurological diseases,” he says.
In Alzheimer’s disease, for example, astrocytes do not regulate neurotransmitters, although this is their basic function, Dulla explains. Problems such as brain injury and epilepsy occur. For many years, scientists have speculated that this problem may be due to a lack of protein or a mutation that causes the protein to fail.
“Extracellular potassium formation in the brain is thought to contribute to epilepsy and migraine pathologies,” says Armbrester. “This new study allows us to build astrocytes