Key to Wound-Healing May Be Explained in Fish Tail
WEDNESDAY, June 3 -- Hydrogen peroxide -- commonly used to prevent infection in cuts and scrapes -- also may rally healing cells to wounded tissue, new research has found.
U.S. researchers have discovered that when the tail fins of zebra fish are injured, a spurt of hydrogen peroxide is released from the wound and into the surrounding tissue. In response to the summons from the hydrogen peroxide, white blood cells travel to the wound and start healing it, they say.
"We've known for quite some time that when the body is wounded, white blood cells show up, and it's really a spectacular piece of biology because these cells detect the wound at some distance," Timothy Mitchison, a professor of systems biology at Harvard Medical School, said in a news release.
"But we haven't known what they're responding to. We do know something about what summons white blood cells to areas that are chronically inflamed, but in the case of an isolated physical wound, we haven't really known what the signal is," he added.
While human and zebra fish genomes share many similarities, it's not clear whether the same hydrogen peroxide alarm system summons white blood cells to wounds in humans, the researchers noted in their study, published in the June 4 issue of the journal Nature.
In humans, hydrogen peroxide is produced primarily in the lungs, gut and thyroid gland. Because hydrogen peroxide is especially present in the lungs and gut, Mitchison and colleagues suggest it may play a role in diseases in those areas that involve unnatural levels of white blood cells, such as asthma, chronic pulmonary obstruction and some inflammatory gut diseases.
"Our lungs are supposed to be sterile; our guts are anything but," Mitchison said in the news release. "It's very logical that both those tissues produce hydrogen peroxide all the time. Perhaps in conditions like asthma, the lung epithelia is producing too much hydrogen peroxide because it's chronically irritated, which, if our findings translate to humans, would explain inappropriate levels of white blood cells. This is certainly a question worth pursuing."
Posted: June 2009