Frog regrows lost leg The amazing axolotl
An African clawed frog has regenerated (regrown) a working leg after it was lost, thanks to a new treatment that could one day help other animals.
Some animals have a natural ability to regrow lost limbs. The African clawed frog is not one of them, but as an amphibian (an animal that lives both on land and in water), it is closely related to many of those that can. Researchers at Tufts and Harvard universities in the US wanted to see if they could activate some hidden regenerative powers in the frog. They created a special gel containing five different drugs and applied it using a small cap called a BioDome. The BioDome was sealed for 24 hours over the wound where the frog’s leg used to be. In the 18 months after the cap was removed, the frog grew a new, fully working leg.
The chemicals in the mixture were all chosen for their particular effects. For example, one was used to block the chemical signals that tell the body to form protective scar tissue over a wound, because scars stop limbs from growing back. The BioDome recreated the conditions in which the frog’s embryo (its earliest stage of growth) develops. The new leg was missing some toenails and webbing but the frog could still use it for swimming. In an article for the website The Conversation, the researchers said they would now try to work out what was missing from the treatment, to grow a more complete leg. “Once we identify these signals, adding them to the drug treatment could potentially fully reverse limb loss in the future,” they wrote. Researcher Nirosha Murugan, of Tufts University, said the experiment suggested that frogs “and perhaps other animals” have a hidden ability to regrow limbs, which can be “triggered into action”. She and her colleagues plan to try the same experiment with mice. The team hope that one day in the near future, similar methods could be used to regrow human limbs.
Of all the animals that can regrow body parts, perhaps the most impressive is the axolotl.
This strange species is known as the “Peter Pan of amphibians” because it never grows up – it lives its whole life in the water, rather than developing to live on land as other amphibians do. Apart from getting bigger, axolotls also look the same for their entire lives. They can regrow almost any body part, from their tail to parts of their brain. Recently, they’ve become famous thanks to the video game Minecraft, where players can breed axolotls to gain rewards.