Radiation exposure antidote one step closer, scientists say

CHARLOTTESVILLE, Va., June 1 (UPI) -- The risk for nuclear attack, terror attack with a dirty bomb or meltdown of a nuclear plant is great enough that scientists are searching for antidotes to radiation exposure.

Scientists at the University of Virginia say they have identified several compounds that show promise in helping cells survive the effects of ionizing radiation, though more research is needed to see if they could actually work in humans.

While previous research suggests radiation exposure is not the greatest threat from a dirty bomb, depending on the materials used to construct it, the chance of a major nuclear disaster by 2050 has been said to be about 50 percent and chance for a nuclear detonation during the next decade has been said to be somewhere between 10 and 30 percent.

The only treatment for lethal doses of radiation is making patients comfortable until they die, which scientists point out isn't much of a choice.

While they don't expect to find one magic bullet to prevent the progressive damage radiation exposure causes, identifying a group of molecules that appear to slow or stop cell damage after exposure could lead to a treatment.

"A lot of us in this field think it will be a cocktail of things you take," Dr. John Lazo, a researcher at the University of Virginia, said in a press release. "And if you think you need cocktails, you need the individual ingredients. That's why we think this is pretty important -- because it's providing new ingredients for that cocktail."

For the study, published in the journal ACS Chemical Biology, the scientists screened a library of 3,437 drugs and compounds looking for those that may keep stem cells in the body alive long enough to repair the damage from radiation.

Using 3D computer models, they identified 33 compounds in the library that significantly reduced cell death in cells exposed to radiation. Of these, rapamycin was shown to be the most effective, though it has been seen in previous research to extend the lives of worms and flies, so the results did not surprise the scientists.

Based on their work, and saying more research is needed both to identify more compounds and test what has been found, the researchers say a combination of two or three compounds is likely to be the most effective -- admitting, in the meantime, they have no idea yet.

"If you're exposed to a very, very high dose, it's rapid deterioration and immediate death," Lazo said. "It's the lower doses that people -- particularly governments -- are concerned about. The type of exposure that might result from a dirty bomb or a nuclear accident. How do we alleviate the effects? What's the antidote? Right now, we just don't have anything."