June 24, 2013
Limb Regeneration Clues Lie In Finger Nail Growth
I recently read Caleb Villarreal’s blog about fingernails.
One of the big mysteries of the world, although you may not know it, is the fact that you fingernails grow back. Really think about that for a couple of seconds. There is no other part of your body, besides your hair, that actually grows back at such a fast rate. Even more intriguing is the fact that the bone and tissue under the nail has this same type of regenerative properties.
As of right now, we really have little information about why and how our nails are able to grow at such a rate and what makes these parts of our bodies are so different compared to other parts. Dr. Mayumi Ito at NYU School of Medicine hopes to change this as he explores these ideas and how we could possibly apply these regenerative properties to other limbs that may have been lost.
His approach to exploring these ideas is actually very straight forward. He was able to explore this idea by amputating fingertips of mice. He found that a specific protein network was essential to the regeneration of their fingertips. He was able to determine that the protein network called Wnt signal network could not only determine whether the limb grew back, but also how much grew back. They found that they could turn off this Wnt signal network and the limbs would not grow back at all, but if they turned it on, the limbs did. They found that not only could they grow the limb back in mice when they turned on this signal network, but they could also grow the limb back past what is usually grown back.
The next step of this research would be to explore the individual parts of the Wnt signal network. Dr. Ito and his team will have to look into the molecular triggers that cause the stem cells of the nails to grow and how they can control these triggers. They will then have to be able to use those triggers with the fingernail stem cells to apply those to the different parts of the body to help regenerate the larger limbs that have been lost over time. There isn’t any research into whole limb regeneration yet because there hasn’t been something this advanced besides the research into stem cells with other animals. This research could eventually become very controversial because it is in the realm of creating limbs and body parts.
As we go into the 21st century, there are about 1.7 million people within the United States that have amputated limbs. Whether they are a war veteran that has been fighting for our country or victims of uncontrollable accidents, all of these people can benefit from this new information. Rather than go through the painful surgery of connecting a prosthetic limb to your nervous system to provide full range of motion and complete control of their limb, they may eventually be able to grow their limb back to the way it was before, and maybe even better than before.
Image Credit: Thinkstock.com