TEMPO.CO, Jakarta - Mammals can regenerate the tips of their fingers and toes after amputation, and now new research shows how stem cells in the nail play a role in that process.
A study in mice, published today in the journal Nature, reveals that chemical signal that triggers stem cells to develop into new nail tissue and also attracts nerves that promote nail and bone regeneration.The findings suggest nail stem cells could be used to develop new treatments for amputees.
In mice and people, regenerating an amputated finger or toe involves re-growing the nail. But, whether the amputated portion of the digit can regrow depends on exactly where the amputation occurs. If the stem cells beneath the nail are amputated along with the digit, no regrowth occurs, but if the stem cells remain, regrowth is possible.
To understand why these stem cells are crucial to regeneration, researchers turned to mice. The scientists conducted toe amputations in two groups of mice: one group of normal mice, and one group that was treated with a drug that made them unable to make signals for new nail cells to develop.
By five weeks after amputation, the normal mice had regenerated their toe and toenail. But the mice that lacked nail signal failed to regrow either their nails or the toe bone itself, because the stem cells lacked the signals that promote nail-cell development. When the researchers replenished these signals, the toes regenerated successfully.
In another experiment, the researchers surgically removed nerves from the mice toes before amputating them. This significantly impaired nail-cell regeneration, similar to what happened to the mice that lacked the signals to produce new nails. Moreover, the nerve removal decreased the levels of certain proteins that promote tissue growth. Together, the results show that nail stem cells are critical for re-growing a lost digit in mice. If the same turns out to be true in humans, the findings could lead to better treatments for amputees.
ISMI WAHID
