Radiation risksStudy promises possible therapy for radiation sickness
Studies of potential radiation therapies suggest they would be effective in humans only if administered within a few minutes or hours of radiation exposure, thus making them impractical for use in response to events involving mass casualties; the larger time window for administering a new 2-drug regimen ofeers the prospect that it could become a mainstay of the response to public health threats such as a nuclear power plant accident or nuclear terror attack
A combination of two drugs may alleviate radiation sickness in people who have been exposed to high levels of radiation, even when the therapy is given a day after the exposure occurred, according to a study led by scientists from Dana-Farber Cancer Institute and Children’s Hospital Boston.
Mouse studies of other potential therapies suggest they would be effective in humans only if administered within a few minutes or hours of radiation exposure, thus making them impractical for use in response to events involving mass casualties. In contrast, the larger time window for administering the 2-drug regimen raises the prospect that it could become a mainstay of the response to public health threats such as a nuclear power plant accident or nuclear terror attack.
A Dana-Farber Cancer Institute release reports that in a paper published online by the journal Science Translational Medicine, the scientists report the beneficial effects, in mice, of a combination of a fluoroquinolone antibiotic (similar to the commonly used human antibiotic ciprofloxacin, or “Cipro”) and a synthetic version of the natural human infection-fighting protein BPI. Mice that received the combination a day after being exposed to high doses of radiation fared far better than mice that received neither or only one of the agents. Whereas radiation exposures of that magnitude almost always prove fatal within a month, 80 percent of the mice that received the two agents were alive and apparently healthy a month into the study.
The study’s lead author is Eva Guinan, MD, of Dana-Farber, and the senior author is Ofer Levy, MD, Ph.D., of Children’s Hospital Boston.
The investigators also found that the ability to generate new blood cells — which can shut down in the aftermath of radiation exposure — rebounded much more quickly and vigorously in the mice treated with fluoroquinolone and rBPI21 (the synthetic version of BPI), potentially contributing to their return to health.
“Both fluoroquinolone antibiotics and rBPI21 have been shown to be quite safe in humans,” says Levy. “Their combined effectiveness in our study involving mice is an indication that they may be equally beneficial in people.”
The release notes that the research potentially represents a major step in the U.S. government’s efforts to build a stockpile of therapies to counter radiological dangers.
“There is great interest in creating systems for dealing with the short- and long-term health risks of a significant release of radiation, whether from an accident at a nuclear power plant, an act
