Frogs Regrow Limbs With New 24-Hour Treatment—And Humans Might Be Able To, Too

Body and limb regeneration has been, until now, the stuff of sci-fi movies and often comes to a formidable villain at the most inopportune times. But in the “real world,” things aren’t quite like that, and patients with amputated limbs are faced with the loss seemingly forever.

However, this may soon change, and it starts with frogs. 

A new 24-hour treatment has shown that it is feasible to regenerate “fully functional and touch-sensitive” limbs in frogs in that time frame. This is thanks to the fact that frog cells “remember” how to grow frog legs.

They did come from somewhere in the first place, after all.

These miracle-working frogs were able to pull this off with the help of scientists at Tufts University and Harvard University. The team developed a sort of wearable filled with a cocktail of drugs “involved in normal animal development and tissue growth,” a device described to Fast Company as an “isolated chamber for regeneration.” 

These drugs all had their individual benefits, such as “ tamping down inflammation, inhibiting the production of collagen which would lead to scarring, and encouraging the new growth of nerve fibers, blood vessels, and muscle.” 

This also meant that it stopped the body’s “natural tendency” of “closing off the stump,” encouraging the limb to grow instead, as the team explains in a statement.

Having had their back legs amputated at the knee, the frogs were then given this mix in a BioDome, a silicone sleeve that covers the wound. These stayed on for 24 hours before being removed. 

Over 18 months, the frogs were able to grow their legs back—including “fingerlike projections with significant nerve, bone, and blood vessel regrowth.” They were also responsive to touch, and enabled the frogs to begin swimming again. 

Some frogs were given an empty BioDome, which saw “limited” limb regrowth but nothing comparable to the fully regenerated legs. And frogs without any treatment didn’t regrow their limbs at all, as was predicted. 

“We’ll be testing how this treatment could apply to mammals next,” one of the study’s lead authors, Michael Levin, states. Further investigation of drug and growth hormones might result in regeneration that is “even more functionally complete.” 

[via Fast Company and Science News, image via David J. Stang (CC BY-SA 4.0)]