Axolotls, a type of aquatic salamander, have the ability to regrow their limbs after injury or amputation. Researchers have made a groundbreaking discovery about the complex process behind this superpower, which could lead to new human healing methods and gene therapies.
The study found that a substance called retinoic acid is responsible for signaling what body parts an axolotl’s injured cells should regenerate into. This molecule is also important in the development of human embryos, but humans lose the ability to “listen” to its regenerative cues while in utero.
Researchers used genetically modified axolotls that glow green when retinoic acid is activated at the site of amputations. They discovered that a single enzyme breaks down retinoic acid in axolotl bodies, controlling its levels and preventing over-regeneration. By blocking this enzyme, they observed the same “Frankenstein” effects as before.
The study suggests that humans could learn from axolotls by understanding how their cells use natural levels of retinoic acid for regeneration. Axolotl cells go through a process called dedifferentiation when injured, allowing them to respond to retinoic acid signals and build new limbs. Human cells, however, don’t dedifferentiate, leading to scarring instead of regeneration.
This research could lead to new technologies that help humans heal wounds and prevent scarring. While human limb regeneration is still far off, understanding more about retinoic acid signaling could speed up the process and make it possible for humans to regrow lost limbs in the future.
Source: https://edition.cnn.com/2025/06/12/science/axolotl-limb-regeneration-human-genes