Resuscitation of cells in a pig's brain could change medication

It is easy to ignore our underlying ignorance about how the brain produces consciousness through the highly successful research published this week in the journal Nature. Yet this study could lead us to this seminal moment of understanding the human brain itself. More importantly, this work could strengthen research to better repair our most complex organ.

Although Yale researchers, authors of the publication, have made a leap forward in medical neuroscience, this work does not bring us much closer to the first brain transplant. Suspending a conscious brain in a solution tank also remains a sci-fi topic for the moment.

Whatever the case may be, the experience marks an important scientific achievement. The researchers retrieved chopped pork heads at a food processing plant, surgically removed the brains and connected some arteries to a device they dubbed BrainEx, a machine made from commercially available parts. manufactured by 15 different companies. One researcher told me that the lab, filled with the clever array of tubes, pumps, badyzers, reservoirs and dialysis membranes "looks like a garbage cabinet in an often repaired spaceship".

BrainEx then pumped the brain with the artificial blood product Hemopure, a processed hemoglobin made from cow's blood, which is key to the project's success. Since Hemopure is used during transplants to keep organs alive longer, it makes sense that it was used to revitalize the cells of a brain without blood and at room temperature for four hours.

The fact that some people have managed to survive hypothermia so severe that their hearts no longer beat has probably given researchers the hope that their exploit with BrainEx could work. But the big breakthrough of BrainEx is not restoring dead tissue: it has long been known that cell function in tissues can be observed well after the death of the host organism, and scientists have even done so with human brain tissue.

BrainEx offers the ability to keep much of the brain alive separate from the body. This represents a new research model for experimental work on a range of brain injuries, not just those where the heart stops. By isolating the brain and connecting it to BrainEx, scientists could potentially add various drugs to the artificial bloodstream to see how they work and experiment with different repair procedures on a living brain without dealing with the rest of the body.

While the BrainEx technique raises questions about the blurred line between life and death, we are still far from seeing the practical applications of the study unfold in the country's hospitals. In the BrainEx study, the scientists inflicted serious damage to the brain that he kept alive – they blocked all major arteries supplying the brain and brainstem, with the exception of two major ones. In practice, this would cause many strokes, especially at the brainstem, which is responsible for directing all exits and entrances of the brain.

And while scientists have shown that they are able to pump artificial blood through the arteries of the brain, many small blood vessels called capillaries have remained closed. The study presented the data in bar graph form without specifying the exact figures, but it appears that about 10% of the capillaries have not opened. A brain with 10% of its capillaries suddenly closed would be terribly dysfunctional, with widespread brain cell death.

Prove that individual cells can perform basic metabolic functions or send a neural impulse when stimulated is far from activating the complex networks that generate awareness, a process that we do not yet fully understand. A considerably more advanced technique producing much less brain damage would probably be needed to visualize the alpha and beta electroencephalography waves that we badociate with consciousness.

Looking at the possibility of a brain transplant, we currently have no way of connecting a brain to the spinal cord, or brainstem to the nerves of the head and neck. A brainstem stroke can leave a patient temporarily or permanently without any control of the body and only limited eye movement. The results of brain transplantation would be much worse: no sense, hearing or sight, and no valid means of communicating with the outside world. The results of such a procedure, which no scientific review committee would approve, would be even more horrible than what the Italian surgeon in charge of the "transplant of the head" claims to want one day to do.

The body is not a machine and death does not tip a switch. Biomedical scientists know this intellectually, but the law and society do not understand this medical fact very well. Despite our current scientific limitations, it is not too early to consider the ethics of reviving consciousness in a disembodied brain and wondering if brain transplants should be allowed. In an article accompanying Nature, two bioethicists worry about the meaning of a life support system for people waiting for an organ transplant. Could death become so vague a problem that families do not want to separate themselves from the remaining organs of their loved one while waiting to see if their brains could be revived? I suspect that when we face this dilemma, we will have artificial livers, hearts and kidneys developed in the laboratory to fill such a void.

The future is coming, with technologies that can be used for good or for bad, but this study deserves more celebration than consternation. This new research tool offers better treatments for cerebrovascular accidents, anoxic or traumatic brain injuries, etc.