Drug that could turn soldiers into super-survivors

Enduring natural disasters, wars or terrorist attacks could soon be a cakewalk, for scientists have now found a drug that could virtually turn an injured person into a "super-survivor", by preventing certain biological mechanisms from shutting down.

The drug has so far only been tested in animals.

And if it has a similar effect in humans, it could vastly improve survival from horrific injuries, particularly in soldiers, by allowing them to live long enough to make it to a hospital.

Loss of blood is the main problem with many battlefield injuries, and a blood transfusion the best treatment, although replacing lost fluid with saline can help. But both are difficult to transport in sufficient quantities.

"You can't carry a blood bank into the battlefield. What we're looking for is a pill or a shot that would keep a person alive for long enough to get to them to a hospital," New Scientist quoted Hasan Alam of Massachusetts General Hospital in Boston, as saying.

When the body loses a lot of blood, it tries to compensate by going into shock.

This is a set of emergency measures to raise blood pressure and conserve energy, such as increasing heart rate and shutting down expression of some proteins.

However, if the body stays in shock for more than a short time, it can lead to organ failure, and death soon follows.

Recent studies have suggested that around 6 or 7% of genes change their expression in response to shock, via the removal of "epigenetic", chemical additions to the genome called acetylations.

As histone deacetylase (HDAC) inhibitors can prevent the removal of such acetylations, Alam wondered if these drugs might improve survival after blood loss.

The team previously showed that valproic acid, an HDAC inhibitor already used to treat epilepsy, increased survival rates in rats that had lost a lot of blood.

It seemed to be doing this by preventing acetylation, causing certain "survival pathways" to remain switched on.

Alam repeated the study in pigs-he anaesthetised the animals, drained 60% of their blood, and subjected them to other injuries before giving them a saline transfusion.

He then injected some of the pigs with valproic acid, gave others a blood transfusion and left the remainder untreated.

Just 25% of the pigs receiving only saline survived for 4 hours - the typical time it takes to get hospital treatment - while 86% of those injected with valproic acid survived.

All those that had a blood transfusion lived.

Alam is currently repeating the trial to make sure valproic acid does not hinder survival in the longer term.

If that happens, he will apply for permission to do human trials by the end of the year.

The study has been published in the journal Surgery.