By Chris Skeldon 
Scientists have been able to reactivate blood circulation and other cellular functions in pigs that died shortly before, a study reveals that offers hope for future use of medicine, although it raises ethical questions.
In 2019, a team of researchers in the United States surprised the scientific community by successfully restoring cellular function in pigs’ brains a few hours after they were decapitated.
In their latest investigation, published Wednesday in the magazine temper natureThese same scientists sought to extend this technique to the entire body of the animal.
Scientists caused a heart attack in anesthetized pigs, cutting off blood flow and starving their cells of oxygen. Without oxygen, mammalian cells would die.
An hour later, the researchers injected the bodies with a fluid containing pig blood (taken while they were alive) and a synthetic form of hemoglobin – the oxygen-carrying protein in red blood cells. They also administered drugs that protect cells and prevent blood clots from forming.
The blood began to flow again and many cells began to function again, including vital organs such as the heart, liver and kidneys, over the next six hours.
“These cells were working hours later, when they shouldn’t. This shows that the disappearance of cells can stop.” Nenad Sestan, lead author of the study and researcher at Yale University confirmed.
Study co-author David Andrejevic, also of Yale University, added that under a microscope, it was difficult to differentiate a normal and healthy organ from one that had been treated postmortem.
Save the lives of people waiting for transplant
The team hopes the technology, called OrganEx, will be used to “save organs” by prolonging its action and saving the lives of people waiting for a transplant.
OrganEx may also allow new forms of surgery, giving “more medical leeway,” according to Anders Sandberg of the University of Oxford.
Medical, ethical and philosophical issues
However, thisThis technique raises various questions, such as medical, ethical and even philosophical ones.
Among the doubts “increased risk that resuscitated persons will not be able to recover from a life support condition,” Brendan Barnett, a bioethicist at New York University’s Grossman School of Medicine, cautioned in a commentary published by the journal Parallel.
For Sam Parnea, of the Department of Medicine at the same university, this “really fascinating” study also shows that “death is a biological process that is treatable and reversible after hours.”
Ultimately, the medical definition of death may need updating, according to Benjamin Curtis, a moral philosopher at Nottingham Trent University in the UK.
“Looking at this study, many of the processes we thought were irreversible wouldn’t be”He told Agence France-Presse (AFP).
“And according to the current medical definition of death, a person may not actually die for hours” through some operations.he added.
This finding could also spark a debate about the ethics of such actions.
Especially since nearly all of the pigs made vigorous head and neck movements during the experiment, according to Stephen Latham, one of the study’s authors.
“It was very surprising to the people in the room.”the world admitted, in statements to reporters.
The origin of these movements is still unknown, but the researcher emphasized that at no time was electrical activity recorded in the animals’ brains, thus ruling out the recovery of consciousness.
However, head movements are “a major concern,” said Benjamin Curtis, because recent neuroscience studies have indicated that “conscious experience can persist even when electrical activity in the brain cannot be measured.”
“This technique could cause suffering to pigs and could cause suffering to humans if used on these.”He stressed, calling for more studies on this technique.