A drug originally used to treat iron poisoning has been found to significantly boost the body's own ability to heal and re-grow injured bones, according to a study from the University of Alabama at Birmingham. Researchers injected the drug desferoxamine (or DF), which is designed to reduce iron overload, into injured mouse bones. DF was found to trigger the growth of new blood vessels, which in turn initiated bone re-growth and healing. The bone density surrounding the injury more than doubled to 2.6 cubic millimeters in treated bones versus 1.2 cubic millimeters in untreated bones. Researchers say the blood vessel growth and bone healing was achieved through a cell pathway that helps the body respond to low oxygen levels, a common problem when bone fracture and disease affect blood supply.
The research tests were performed in conjunction with a bone lengthening procedure proven to aid in bone healing and commonly used in children and adults. Anesthetized mice had one leg bone bisected and a pulling device was attached to stretch the bone gap for 10 days.
During the stretching, the bone gap received five does of DF. Two weeks after the last DF dose, X-rays of the mice legs were taken to measure bone regeneration. Along with increased bone density there were significant increases in the number of new blood vessels with high connectivity between them.
New blood vessels help regenerate bone of equal, or generally greater, strength than the original bones. The authors of the study believe this discovery opens doors to new, safe, and affordable ways to accelerate bone repair. Current treatments use expensive complex proteins costing thousands of dollars per dose compared to DF which is said to cost hundreds.
Co-author Chao Wan claims, "The results from this study are a milestone for future studies looking at other compounds and agents to improve new-blood-vessel growth in skeletal and other tissues that need adequate blood supply to regenerate."
Another study published in the Proceedings of the National Academy of Sciences shows the potential of using stem cells to repair major injuries involving the loss of bone structure.
The study showed that using scaffolding laced with stem cells can dramtically improve bone density, streghth and regrowth in healing bones. In the study scientists stimulated a broken bone in mice. The gap in the bone was bridged with a scaffolding that allowed bone to regrow thus healing the break. The researches used neutral scaoffolding, and two kinds of stem-cell laced scaffolding - bone marrow-derived mesenchymal adult stem cells and amniotic fluid fetal stem cells.
Results showed that the stem-cell covered scaffolding produced far better results that the neutral scaffolding. There was little difference though between the different kinds of stem cells. This is important because it is theorized shows that the non-controversial adult-stem cells are less likely to develop into tumors instead of the desired target cell types.
"Massive bone injuries are among the most challenging problems that orthopedic surgeons face, and they are commonly seen as a result of accidents as well as in soldiers returning from war," said the study's lead author Robert Guldberg, a professor in Georgia Tech's Woodruff School of Mechanical Engineering. "This study shows that there is promise in treating these injuries by delivering stem cells to the injury site. These are injuries that would not heal without significant medical intervention."