In a new study researchers have figured out how mammals have the ability to regrow the tips of their toes and fingers after the have been amputated. Stem cells located in the nail play a major role in the process, reports Discovery News.
A study that was detailed in the journal Nature explained how stem cells in the nails of mice not only caused the regrowth of nail tissue but also sent a chemical signal to attract nerves, the first step in regrowth of nails and bones, according to Discovery News.
In both mice and people the regeneration of the tip of a finger or toe depends on where the amputation is made; only if stem cells remain beneath the nail the digit will regrow.
Researchers conducted an experiment where they separated a group of mice into two groups. One group consisted of normal mice and the other mice were given a drug that made it so they could not produce the signals to create new nail cells. They then had toes amputated.
The results were best described by Discovery News:
They found that the signals that guided the stem cells' development into nail cells were vital to regenerating amputated digits. By five weeks after amputation, the normal mice had regenerated their toe and toenail. But the mice that lacked the 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 an additional experiment the researchers removed nerves from each mouse's toes before amputation; this caused a similar impairment in the regrowth of tissue as the drug inhibiting the signals had.
When the two results are combined together it shows that stem cells are critical for the regrowth of tissue in mice. Researchers hope that this will also apply to humans so that they can develop better treatment for amputees, reports Discovery News.
