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Pig's brain function restored hours after death

Scientists have restored activity in a pig’s brain — hours after its death. Treatment was pumped into the cells for six hours. The findings challenge assumptions about the irreversible ending of brain function after death. The scientists behind the research claim the development could help in the study and treatment of brain disorders. Was the pig’s brain conscious? The team from Yale University in the US stressed the brain lacked any recognisable global electrical signals associated with normal brain function. “At no point did we observe the kind of organised electrical activity associated with perception, awareness, or consciousness,” said co-first author Zvonimir Vrselja, an associate research scientist in neuroscience. “Clinically defined, this is not a living brain, but it is a cellularly active brain.” But after restoring the brain, they observed some basic functions return — functions previously thought to cease seconds or minutes after oxygen and blood stop circulating in the brain of a deceased animal. How was function restored to the brain? Four hours after the pig’s death, they connected the vasculature of the brain to circulate a uniquely formulated solution they developed to preserve brain tissue. This system is called BrainEx. They found neural cell integrity was preserved, and certain neuronal, glial, and vascular cell functionality was restored. A breakthrough in brain research “Previously, we have only been able to study cells in the large mammalian brain under static or largely two-dimensional conditions utilising small tissue samples outside of their native environment,” said co-first author Stefano G. Daniele, an M.D./Ph.D. candidate. “For the first time, we are able to investigate the large brain in three dimensions, which increases our ability to study complex cellular interactions and connectivity.” While the advance has no immediate clinical application, the new research platform may one day be able to help doctors find ways to help salvage brain function in stroke patients or test the efficacy of novel therapies targeting cellular recovery after injury, said the authors. “This line of research holds hope for advancing understanding and treatment of brain disorders and could lead to a whole new way of studying the postmortem human brain,” said Andrea Beckel-Mitchener, chief of functional neurogenomics at the NIH’s National Institute of Mental Health, which co-funded the research. What is the potential ethical implication of this? The team stressed any future study involving human tissue or possible revival of global electrical activity in postmortem animal tissue should be done under strict ethical oversight. “Restoration of consciousness was never a goal of this research,” said co-author Stephen Latham, director of Yale’s Interdisciplinary Center for Bioethics. “The researchers were prepared to intervene with the use of anaesthetics and temperature-reduction to stop organised global electrical activity if it were to emerge. Everyone agreed in advance that experiments involving revived global activity couldn’t go forward without clear ethical standards and institutional oversight mechanisms.” There is an ethical imperative to use tools developed by the Brain Initiative to unravel mysteries of brain injuries and disease, said Christine Grady, chief of the Department of Bioethics at the NIH Clinical Center. “It’s also our duty to work with researchers to thoughtfully and proactively navigate any potential ethical issues they may encounter as they open new frontiers in brain science,” she said. Professor Dominic Wilkinson, Director of Medical Ethics, at the University of Oxford told Euronews, “It might lead to further developments that could help restore or preserve the function of a damaged brain”. Watch the interview with Professor Dominic Wilkinson on the player above.