Scientists Revive a Brain Outside the Body – Despite It Being a Dead Pig's Brain

In a breakthrough that seems straight out of a science fiction novel, researchers have successfully revived and maintained pig brains outside their bodies hours after death. This groundbreaking study, published in the journal EMBO Molecular Medicine, brings to life the concept of a “brain in a vat” – a staple of philosophical thought experiments and sci-fi narratives.

Led by Dr. Zhiyong Guo and colleagues, the research team at Sun Yat-sen University in China developed an ex vivo normothermic machine perfusion (NMP) system that can restore circulation and metabolic activity in isolated pig brains. This system mimics the return of blood flow after cardiac arrest, providing oxygenated, nutrient-rich blood to the brain tissue.

The study’s most striking finding was that the addition of a functioning liver to the brain perfusion circuit significantly reduced post-cardiac arrest brain injury. Brains perfused with liver assistance showed improved neuronal viability, better-preserved cellular structures, and even demonstrated electrocortical activity – a sign of potential brain function.

To put it simply, the researchers created a life-support system for brains, complete with artificial circulation. By adding a liver to this system, they found that the brain was better protected from the damage typically seen after cardiac arrest. The liver seemed to act as a protective guardian, helping the brain recover from the trauma of oxygen deprivation.

The significance of this research becomes clear when we consider that severe brain damage is a common and often fatal consequence of cardiac arrest. Previous studies suggested that the brain could only tolerate 5 to 8 minutes of ischemic injury, leading to extremely low survival rates for cardiac arrest patients.

In this groundbreaking experiment, the researchers first induced cardiac arrest in pigs, then separated their brains from their bodies. After 50 minutes, they connected the isolated brains to an external life support system via intubation, creating a life-sustaining system for brain revival. The results were remarkable: the pig brains were successfully “revived,” regaining brain function and maintaining vitality for a certain period. The research team voluntarily terminated the experiment after 6 hours.

The life support system, developed by the team, incorporates not only artificial heart and lung components but also utilizes blood normothermic perfusion technology to maintain a living pig liver. This setup provides fresh, oxygenated, and metabolically stable blood circulation to the isolated pig brain connected to the device.

The study revealed that under the support of a cardiopulmonary resuscitation system alone, the isolated brain showed significant edema, a marked decrease in neuronal viability, and gradual disappearance of brain electrophysiological activity. However, with the support of the external cardiopulmonary-hepatic composite life system, brain edema was significantly reduced, neuronal viability and cellular microstructures were notably improved, and brain electrical activity could be restored and maintained.

This research has far-reaching implications for our understanding of brain death and the potential for reviving brain function after cardiac arrest. It also opens up new avenues for studying brain diseases and testing potential treatments outside the body.

However, it’s important to note that this study was conducted on pig brains, and the results cannot be directly applied to humans. The ethical implications of such technology, if ever applied to human brains, would be profound and require careful consideration.

As we inch closer to what once seemed purely fictional, the line between science fiction and reality continues to blur. This study reminds us that today’s outlandish concepts might just become tomorrow’s groundbreaking science, potentially revolutionizing our approach to treating cardiac arrest and brain injuries.