Humans can’t regenerate their limbs, unless it’s the stuff of science fiction. A fascinating study in the journal ‘Science Advances’ suggests we do however have a hidden ability to regrow cartilage in the body. This marks the first time the scientific community has systematically looked for signs of regeneration in human tissue. Such a finding could assist in the treatment for joint injuries and even arthritis.
Can the human body better repair itself?
A team of American researchers at Duke University used mass spectrometry techniques on 18 joint tissue specimens from the hips, knees or ankles of patients who underwent surgery. They identified a mechanism by which humans repair tissue around ankles, knees and hips. It’s similar to the mechanism amphibians use to regrow new legs. “We believe that an understanding of this ‘salamander-like’ regenerative capacity in humans, and the critically missing components of this regulatory circuit, could provide the foundation for new approaches to repair joint tissues and possibly whole human limbs,” senior author Dr Virginia Byers Kraus, a professor in the medicine, pathology and orthopaedic surgery departments at Duke University School of Medicine, said in a press release.
Channelling our 'inner salamander'
Salamanders and other animals with the ability to regrow body parts have a type of molecule called microRNA that helps to regulate joint tissue repair. The researchers found that humans also use microRNA. “We were excited to learn that the regulators of regeneration in the salamander limb appear to also be the controllers of joint tissue repair in the human limb,” lead author Dr Ming-Feng Hsueh said. “We call it our ‘inner salamander’ capacity.” According to the researchers, microRNAs could be developed into medicines that prevent, slow or reverse arthritis. “We believe we could boost these regulators to fully regenerate degenerated cartilage of an arthritic joint. If we can figure out what regulators we are missing compared with salamanders, we might even be able to add the missing components back and develop a way someday to regenerate part or all of an injured human limb,” Dr Kraus explained. “We believe this is a fundamental mechanism of repair that could be applied to many tissues, not just cartilage.”
Is human limb regeneration far off?
“The traditional view has been that cartilage lining the joints throughout the body is all the same and does not repair or regenerate,” Dr Kraus told ‘Newsweek’. “This research shows that cartilage at different sites is different and that cartilage has a natural repair capacity that varies by joint site.” “The implications are far-reaching, suggesting new treatments based on boosting, with regenerative microRNA, the natural human ability to repair cartilage,” Dr Kraus added. “We wonder, might it be possible to someday regenerate a human limb based on a deeper knowledge of how humans and salamanders are alike and unalike.”