Scientists have actually recognized a brand-new hybrid brain cell, sharing characteristics of astrocytes and nerve cells. This discovery might settle longstanding arguments in neuroscience about the function of astrocytes in synaptic transmission.
Researchers have actually found a brand-new hybrid brain cell, bridging the gap between nerve cells and astrocytes. This cell can launch neurotransmitters and may affect conditions like epilepsy and memory consolidation, providing promising paths for neuroscientific research study and potential treatments.
Neuroscience remains in great turmoil. The 2 major families of cells that comprise the brain, nerve cells and glial cells, secretly concealed a hybrid cell, halfway in between these 2 classifications.
For as long as Neuroscience has actually existed, it has actually been acknowledged that the brain works mostly thanks to the nerve cells and their capability to rapidly transfer and elaborate details through their networks. To support them in this task, glial cells carry out a series of structural, energetic, and immune functions, along with stabilize physiological constants.
A few of these glial cells, called astrocytes, thoroughly surround synapses, the points of contact where neurotransmitters are released to send info in between neurons. This is why neuroscientists have actually long recommended that astrocytes might have an active role in synaptic transmission and take part in info processing. The research studies carried out to date to show this have suffered from conflicting results and have not reached a definitive clinical agreement.
By identifying a new cell type with the attributes of an astrocyte and expressing the molecular machinery essential for synaptic transmission, neuroscientists from the Department of Basic Neurosciences of the Faculty of Biology and Medicine of the University of Lausanne (UNIL) and the Wyss Center for Bio and Neuroengineering in Geneva put an end to years of controversy.
The Key to the Puzzle
To validate or refute the hypothesis that astrocytes, like nerve cells, are able to release neurotransmitters, scientists initially inspected the molecular content of astrocytes using contemporary molecular biology techniques. Their objective was to find traces of the equipment essential for the rapid secretion of glutamate, the primary neurotransmitter used by nerve cells.
” The accuracy enabled by single-cell transcriptomics approaches allowed us to show the presence in cells with astrocytic profile of transcripts of the vesicular proteins, VGLUT, in charge of filling neuronal vesicles specific for glutamate release. These transcripts were discovered in cells from mice, and are obviously preserved in human cells. We likewise determined other specialized proteins in these cells, which are essential for the function of glutamatergic blisters and their capacity to communicate quickly with other cells,” says Ludovic Telley, Assistant professor at UNIL, co-director of the study.
New Functional Cells
Next, neuroscientists searched for out if these hybrid cells were practical, that is, able to in fact launch glutamate with a speed equivalent to that of synaptic transmission. To do this, the research group used an advanced imaging strategy that might visualize glutamate launched by vesicles in brain tissues and in living mice.
” We have identified a subgroup of astrocytes reacting to selective stimulations with quick glutamate release, which happened in spatially delimited areas of these cells reminiscent of synapses,” says Andrea Volterra, honorary professor at UNIL and visiting professors at the Wyss Center, co-director of the research study.
In addition, this glutamate release applies an impact on synaptic transmission and controls neuronal circuits. The research group had the ability to show this by reducing the expression of VGLUT by the hybrid cells.
” They are cells that modulate neuronal activity, they control the level of interaction and excitation of the nerve cells,” states Roberta de Ceglia, first author of the research study and senior researcher at UNIL. And without this functional equipment, the research study reveals that long-term potentiation, a neural procedure included in the systems of memorization, is impaired and that the memory of mice is impacted.
Hyperlinks With Brain Pathologies
The implications of this discovery extend to brain conditions. By specifically interrupting glutamatergic astrocytes, the research team demonstrated results on memory debt consolidation, however likewise observed relate to pathologies such as epilepsy, whose seizures were exacerbated. Finally, the research study shows that glutamatergic astrocytes likewise have a function in the guideline of brain circuits included in motion control and could provide healing targets for Parkinsons illness.
” In in between neurons and astrocytes, we now have a brand-new type of cell at hand. Its discovery opens tremendous research study potential customers. Our next research studies will explore the potential protective function of this kind of cell versus memory problems in Alzheimers disease, along with its role in other areas and pathologies than those explored here,” tasks Andrea Volterra.
Referral: “Specialized astrocytes moderate glutamatergic gliotransmission in the CNS” by Roberta de Ceglia, Ada Ledonne, David Gregory Litvin, Barbara Lykke Lind, Giovanni Carriero, Emanuele Claudio Latagliata, Erika Bindocci, Maria Amalia Di Castro, Iaroslav Savtchouk, Ilaria Vitali, Anurag Ranjak, Mauro Congiu, Tara Canonica, William Wisden, Kenneth Harris, Manuel Mameli, Nicola Mercuri, Ludovic Telley and Andrea Volterra, 6 September 2023, Nature.DOI: 10.1038/ s41586-023-06502-w.
Some of these glial cells, understood as astrocytes, totally surround synapses, the points of contact where neurotransmitters are released to transmit information between neurons. These records were discovered in cells from mice, and are apparently maintained in human cells. We likewise recognized other specific proteins in these cells, which are important for the function of glutamatergic blisters and their capacity to interact rapidly with other cells,” states Ludovic Telley, Assistant teacher at UNIL, co-director of the research study.
” In in between neurons and astrocytes, we now have a brand-new kind of cell at hand. Our next studies will explore the possible protective role of this type of cell against memory problems in Alzheimers disease, as well as its function in other areas and pathologies than those explored here,” projects Andrea Volterra.