Even after we die, some of our brain cells may experience one last major explosion in life, a new study released Tuesday suggests. The study found evidence that some “zombie genes” in our brain cells are more often active shortly after death, causing some cells to expand dramatically for hours. The findings will not significantly change our concepts of life and death, but they may have some important implications for the study of post-mortem-induced brain tension.
It’s no secret that our cells can survive and function for a while even after we are clinically dead, before they finally come out. But while almost all cells carry the same genetic information as the next one, different types of cells express this genetic information differently, with different genes turned on or off. off. And when the researchers looked at the gene expression of different cells within “dying brains,” they found specific patterns.
For their study, published in Tuesday’s Scientific Reports, the team looked at samples of brain material donated by patients who have recently undergone brain surgery for epilepsy (surgical treatments can remove parts of the brain involved in the seizure disorder). safely removed). They then mimicked the process of brain death by leaving out the newly taken samples at room temperature for different periods, for up to 24 hours. All the while, the team was collecting information about the cellular and genetic activity of these cells.
In most of the genes they studied, identified as “housekeeping genes” that maintain basic cell function, they found that the genes remained at the same level of activity for the total time 24 hours. In the “neuronal” genes, genes that turned on in the neuron cells responsible for brain functions such as thinking and memory, their activity began to decline after 12 hours.
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However, in a third group of genes, linked to the function of glial cells – the immune and support systems of the brain – gene expression was spiked after “death” and continued for up to 24 hours thereafter. The glial cells themselves expanded significantly in size and even new “arms” developed at the same time as the neurons in these samples decayed.
T.its results do not prove that it is theoretically possible zombies, and it is not even surprising that glial cells are particularly active after death. The cells are likely to respond to the injury and inflammation that goes on in the brain when it receives oxygen after a person’s last moments. But the findings underscore a potential pressure for how much human brain research is done, according to the authors, as many studies rely on post- mortem on the brain.
“Most studies assume that everything in the brain stops when the heart stops beating, but this is not true,” said study author Jeffrey Loeb, head of neurology and rehabilitation at the University of Illinois at Chicago College of Medicine, in a recitation released by the university. “Our findings will be needed to study the bones of the human brain. We have not yet measured these changes. “
One problem is that research on disorders such as Alzheimer’s disease and other forms of dementia often rely on collected post-mortem brain samples 12 or more hours later death. If the conclusions here are valid, many of these studies may be missing important clues left inside dying cells that may later be lost. Loeb and his team hope that ongoing studies will better describe the changes taking place in a dying brain. A possible solution, for example, is to collect brain samples for even faster post-mortem research or to rely more on samples from willing patients undergoing joint brain surgery. at least.
“The good news from our findings is that we now know which genes and cell types are stable, declining, and which will go up over time until the results of studies are available. better understand postmortem brains, ”Loeb said.