Study Explains How Mammals Regenerate Lost Fingertips

Mammals can regenerate a lost fingertip, including bones and skin. A new study has now explained how this process actually works. Researchers said that the finding could help regenerate limbs for amputees.

In humans, re-grown fingertips may not look like the original one, but it has new bone and skin along with nail. Kids can actually have better regeneration of fingertips. But, nobody knew how this growth occurred.

The latest study was conducted by researchers from NYU Langone Medical Center, who used genetically tweaked mice to explain the biochemical reaction after a mammal loses a fingertip.

"Everyone knows that fingernails keep growing, but no one really knows why," said Mayumi Ito, PhD, assistant professor of dermatology at NYU School of Medicine. Also, nobody has ever found how bones and blood vessels grow in the fingertip post an amputation.

According to the researchers, there are self-renewing stem cells in the nail matrix. This nail matrix is present in the nail bed that has many nerve endings and blood vessels, which help in cell growth.

These self-renewing cells use proteins called as the "Wnt signaling network" that are associated with hair and tissue regeneration.

"When we blocked the Wnt-signaling pathway in mice with amputated fingertips, the nail and bone did not grow back as they normally would," said Dr. Ito in a news release.

Interestingly, researchers found that they could alter this pathway to accelerate regeneration in other parts of the body. "Amputations of this magnitude ordinarily do not grow back," added Dr. Ito.

The study could help design therapies for people with amputations. Currently, about 1.7 million people in the U.S. have limb amputations.