Don’t bite that fingernail! Stem cells underneath the nail have been found capable of regenerating finger tips and the tips of toes after amputation. According to Jack Phillips, writing in Epoch Times, mammals, including humans, can regenerate skin and bone at the ends of fingers. The new findings are published in the journal Nature.
Mayuni Ito, at New York University, found stem cells at the base of each toenail that can stimulate not only the nail regrowth but the entire tip of the digit after amputation. “We at least partly retain the mechanisms that operate limb regeneration in amphibians, ” Ito said, according to the publication. “Knowing more about how nail epidermal cells induce digit-tip regeneration may provide direct clues to extend our ability for regeneration.”
Scientists amputated the toes on two groups of mice in the study. One group of mice received no medications and was called the “normal” group. The other group received a drug that makes them unable to develop new nails. They found that the normal group could regenerate the tips of digits in a few weeks, while the treated group could not. When the other mice were taken off the drug, they then could regenerate their toe tips.
Phillips quoted LiveScience.com as reporting that the regeneration of an amputated digit has to do with where the stem cells are located. It said that if the stem cells beneath the nail are amputated along with part of the digit, then there is no regrowth.
Phillips quoted James Monaghan, a regeneration biologist at Northeastern University in Boston, Massachusetts, who told Nature’s website: “It’s really striking that the cellular mechanisms and signaling pathways all seem to be the same as those in salamanders.” Salamanders are capable of regenerating a limb after losing it.
