The application of high levels of oxygen to severed bone facilitates bone regrowth, according to a study presented at the American Society for Biochemistry and Molecular Biology annual meeting in San Diego.
The study, funded by the Defense Advanced Research Projects Agency, was conducted at Tulane University, where researchers have been exploring the molecular foundation of limb regeneration under various circumstances. They have been especially interested in why bone regrowth only occurs in specific parts of the body and what genes, proteins and molecular activities are utilized during bone regrowth.
“What it boils down to is genes that spur regeneration don’t just turn themselves on. They turn on because something signals them. So I thought, maybe it’s oxygen that’s turning them on,” lead researcher Mimi Sammarco, PhD, stated in a press release. “Oxygen is often the primary signal that turns on various genes.”
The researchers used a special incubator to expose a thin bone sample taken from an amputation site in a mouse to high levels of oxygen. They found that the bone responded favorably to 20% oxygen, but only after a certain amount of time has passed since the amputation. If the bone was exposed too early after the amputation, the oxygen had little effect.
“It’s all about timing. Obviously, there’s a sequence in growing things back. And oxygen can push the button that has to be applied at a certain time,” Sammarco stated.
Sammarco emphasized that even a partial regeneration would be a significant improvement for amputees.
“Every effort to direct and control the extension of amputation stump length contributes to the rehabilitation of amputees, while keeping in mind the long-term goal of complete regeneration,” she stated.