The first used a genetic approach, involving mice that had been genetically engineered to respond better to a Wnt signal, then administering purified Wnt via fat particles known as liposomes.
The second strategy involved raising levels of the Wnt protein in normal mice. Both groups of mice had sustained bone injuries.
"Both experiments showed us the same thing, that when Wnt signals were prolonged in an injury site then healing was much more robust," Helms reported. "When we delivered this form of the protein in a little lipid [fat] particle to an injury site, we accelerated the healing quite dramatically."
In fact, within the first three days, those mice had 3.5 times more new bone than the mice in the other groups, according to background information about the study.
Helms and her colleagues believe Wnt causes bone stem cells to divide more and turn into bone-forming cells much sooner.
J. Edward Puzas, a professor of orthopedics and senior associate dean for basic research at the University of Rochester Medical Center, added that the idea might also benefit people who sustain potentially life-threatening fractures as a result of osteoporosis.
In separate ongoing studies, Puzas is finding that the osteoporosis drug Forteo is also useful in healing bones.
The Stanford group is now expanding its work to speed tissue regeneration after skin wounds, heart attacks and stroke.
The American Academy of Orthopaedic Surgeons has more on bone fractures.
SOURCES: Jill Helms, Ph.D., DDS, professor, surgery and plastic and reconstructive surgery, Stanford University School of Medicine, Palo Alto,
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