In recent days, the media and specialized publications have indicated that the discovery of glutamate-releasing astrocytes will revolutionize neuroscience, and although the scientific evidence for the ability of these cells is strong, what this research achieves is more than a shock to science. A dispute that had been going on for years ended. Distracting scientists is important to prove that they are not true, but exist “Different groups of specialized astrocytes with different functions in brain function”, As highlighted in an article published in Nature.
From the Congress of the International Organization for Brain Research, Monica López, researcher and educator at the National School of Higher Studies Unidad Juricula of the National Autonomous University of Mexico (UNAM) clarifies this. No new cell found, and astrocytes in general have received an increasing role in research work. López is devoted precisely to studying the interactions between neurons and astrocytes.
Some scientists have long assumed that these cells could release glutamate, but it was unclear whether they did so in the same way as neurons. Other researchers did not consider it in this way and attributed only their effects on regulating the microenvironment of neurons.
Astrocytes are present in the central nervous system, surrounding neurons and glial cells in large numbers in mammals. They owe their name to their stellar appearance and their activities are even more enigmatic.
It is well known that neurons are capable of receiving, storing and processing information, as well as responding, releasing chemical substances: neurotransmitters. A common one is glutamate. Astrocytes participate in millions of these contractions between neurons.
For many years, it was assumed that astrocytes only support the nutrition of neurons, that they remove neurotransmitters from synapses, and that they maintain neuronal homeostasis. There was evidence that they were capable of interfering with brain activity and behavior in animals. Astrocytes respond to neurotransmitters released by neurons, albeit slowly.
16 years ago, Monica López, the same group that pinpoints glutamatergic astrocytes, led today by Andrea Volterra, says that they demonstrated with various techniques the existence of vesicles “like small aggregates in cells where the cleotransmitter is present.” Later, another scientific team found vesicles in the astrocytes of the hippocampus that released another neurotransmitter. decerin. Controversy centers around these observations as some researchers have been able to replicate the data while others have not.
A new article concludes the discussion. López describes that work by the group of Andrea Volterra of the Department of Basic Neurology and the Weiss Center of the University of Lausanne (UNIL) shows that some astrocytes are associated with vesicles and calcium. According to neuroscientists, the hippocampus, a key part of the brain where most astrocyte information is collected, has different subpopulations, one of which contains the machinery to release glutamate, according to new analysis.
Recent discoveries in the field of astrocytes are an invitation to study their participation in information processing, which is thought to be exclusive to neurons. Defining what information processing is is a challenge. The neuroscientist says that in recent years there has been increasing evidence that astrocytes play a fundamental role in this process.
“Andrea Volterra’s team does Papers Complex,” says the Mexican researcher. More recently, the hypothesis has been investigated using molecular and bioinformatics approaches and genetic tools of cells involved in glutamate exocytosis. Alive. This allowed them to characterize astrocytes, observe the release of glutamate through fluorescence, the selective activation of astrocytes and the increase in calcium associated with such activation, the researcher says.
He pointed out that these techniques are not new and have been in labs for years, “but the way it addresses the research question and makes it right to make a decision without doubt.”
Glutamate of astrocytes participates in diseases such as Parkinson’s This is not a new suspicion. Volterra’s work, López says, shows that if the vesicles can’t be exocytosed, the connectivity of the hippocampus changes, which is associated with memory. It also increases basal dopamine levels, “which may have an impact or effect on the pathology of Parkinson’s because dopamine levels are important in the voluntary movement involved in this disease. The latter is the only possibility for now.”