Glow-in-the-Dark Salamanders May Have Just Unlocked the Future of Regeneration
What if the key to human limb regeneration wasn't buried in sci-fi dreams—but already in your medicine cabinet?
Scientists at Northeastern University have uncovered a breakthrough that's raising eyebrows in both the dermatology and regenerative biology worlds. The chemical at the center of it all? Retinoic acid—a form of vitamin A that's also the active ingredient in isotretinoin, better known as Accutane.
In a new study, which was published in Nature Communications, researchers mapped how axolotls. The Mexican salamander has a freakish ability to regrow limbs using varying concentrations of retinoic acid to guide the regrowth of bones, joints, muscles and skin.
When an axolotl loses a leg, it doesn't just grow back—it grows back perfectly. And scientists now understand more clearly how that biological GPS works.
At the heart of the process is an enzyme called CYP26b1, which breaks down retinoic acid and dictates how much of the chemical floods a given area. Higher levels mean longer bone growth. Lower levels cue the development of feet and digits.
The implications are massive: by controlling retinoic acid levels, scientists were able to create glow-in-the-dark salamanders with either perfectly formed limbs or comically misshapen ones.
While these findings are still at the basic science stage, researchers believe they've taken a major step toward understanding how to activate dormant genetic mechanisms in humans. Because here's the kicker: the genes involved in limb regeneration already exist in our DNA. We just don't know how to switch them back on—yet.
Retinoic acid has long been linked to fetal development, and now it's being eyed as a possible tool to coax adult tissues into reprogramming themselves post-injury. It's not a silver bullet, but it might be part of the recipe.
'We might just need to remind the body what it already knows how to do,' James Monaghan, the study's lead scientist, told Popular Science.
If that's true, the path to real human regeneration might be shorter—and stranger—than we ever imagined.
Glow-in-the-Dark Salamanders May Have Just Unlocked the Future of Regeneration first appeared on Men's Journal on Jun 10, 2025
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The science behind the smell of rain
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