Chemical blocks brain blast injury

A new drug that can protect brain cells from injuries caused by blast trauma, which is common in military and industrial situations and automotive accidents, has been developed by US scientists.

An estimated 10-20% of troops serving in the Middle East conflicts are thought to have been subjected to blast trauma in which shockwaves from explosions or sudden decelerations affecting the head, tearing nerve fibres apart. Repeated exposures to this trauma can lead to impaired cognition, changes in mood and memory loss.

Now a team of scientists at the University of Iowa Carver College of Medicine and led by Andrew Pieper have developed a drug molecule which, when given to mice, can block blast damage, even when the drug is given many hours after the exposure has occurred.

In a series of experiments, experimental mice were exposed to a standardised blast shockwave before undergoing memory tests that involved them recalling the location of a "safe" area.

Untreated control animals spent no more time in the safe zone than would be expected by chance. But animals that received the new compound, even when it was administered up to 24 hours after blast exposure to mimic delays in treatment that could occur in a real-world situation, spent two-thirds of their time in the experimental safe area, indicating that they could remember where it was.

Tissue samples collected from animals treated with the drug also showed significantly reduced signs of damage to nerve cells in the animals' brains.

The researchers speculate in their paper in Cell Reports, where the work is published this week, that the agent works by boosting the activity of an enzyme called nicotinamide phosphoribosyltransferase (NAMPT).

This produces a precursor chemical needed for the synthesis of a substance called nicotinamide adenine dinucleotide (NAD), which plays a critical role in cell metabolism, stress resistance and ageing.

As such, it's likely that the new agent could also be helpful in preventing the damage done by other degenerative diseases, repeated blows to the head sustained during sports, or high-velocity trauma incurred during car accidents. Even better, the chemical is orally active, meaning that it is easy to administer, although the agent has yet to be tested on humans.