Can the "dead" pig brain be "revived"? Chinese scientists have done it

Science Times reporter Bi Wenting

Pig brains have been "resurrected".

Recently, scientists from the Organ Transplantation Center of the First Affiliated Hospital of Sun Yat-sen University and an international team published a paper. They used the world's first "ex vivo brain maintenance technology" to successfully "revive" a pig brain that had been "dead" for 50 minutes.

On October 24, Zhao Qiang, chief physician of the Organ Transplant Center of the First Affiliated Hospital of Sun Yat-sen University, said in an interview with a reporter from Science Times that this was the first time in the world that a pig brain was "resurrected" in vitro.

When scientists tested the "resurrected" pig's head, they found that if you tapped the pig's ear, it would show EEG fluctuations, when you gave it food stimulation, it would show a desire to eat, and when you gave it light stimulation in front of its eyes, it would open its eyes and chase the light. This series of performances shows that the "resurrection" experiment of the pig's brain has completely restored the brain's function. The research team took the initiative to terminate the experiment after 6 hours.

What is “ex vivo brain maintenance technology”?

Zhao Qiang explained that this refers to a set of equipment independently developed by the team, including an artificial heart, artificial lungs, and a living pig liver maintained using blood perfusion technology at room temperature. After the pig's heart stopped beating, the researchers separated the pig's brain from the body. 50 minutes later, the researchers connected these external organs to the cerebral arteries of the isolated pig's brain. The artificial heart provided power, and the artificial lungs oxygenated the blood to discharge carbon dioxide and input oxygen. At the same time, the addition of the liver can metabolize toxins that flow into the brain's blood, providing the isolated pig brain with a life system that supports brain recovery.

"The liver is crucial to restoring brain function, and this is a breakthrough in this study." Zhao Qiang told reporters that in traditional cognition, cardiopulmonary resuscitation is generally used to perfuse the blood flow of patients with cardiac arrest to the brain. However, in this process, the microenvironment and acidic substances in the blood flow have changed. If there is a lack of liver metabolism, the blood with toxic substances suddenly rushes into the brain and "drags the brain to death" in a short period of time.

Talking about the original intention of the experiment, Zhao Qiang expressed the hope that it could provide some new strategies for the rescue of patients with cardiac arrest. This is also an important reason why the team chose pig brains, which are similar to human brains, as experimental subjects.

What is the relationship between cardiac arrest and brain death?

Zhang Ran, deputy chief physician of the Department of Cardiovascular Medicine at the General Hospital of the People's Liberation Army, explained that the most common cause of cardiac arrest is sudden cardiac death, and among these, about 80% of cases are caused by ventricular tachycardia or ventricular fibrillation (VF for short).

Ventricular fibrillation is the most critical type of arrhythmia, in which the heart's ventricles completely lose the ability to pump blood, causing blood circulation to stop immediately. This is one of the most common and deadly causes of cardiac arrest. "Four to six minutes after cardiac arrest, the brain will suffer irreversible damage, and prolonged damage will lead to brain death," said Zhang Ran.

Zhao Qiang said that this experiment proved from the perspective of pigs that the brain can still be "revived" 50 minutes after the heart stops beating. Next, the team will further explore the "revival" research of pigs with cardiac arrest as a whole, hoping to provide new strategies for human cardiac arrest rescue and extend the golden time for rescue.

It is a long road from theoretical verification to clinical application. We look forward to those research results that have stood the test of time shining in clinical applications.