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Regeneration in biology refers to the ability to restore damaged or lost tissues, organs, or body parts. This phenomenon varies widely across species: axolotls can regenerate limbs multiple times, deer regrow antlers annually, and humans can regenerate liver tissue and fingertips (in children). Salamanders exhibit remarkable plasticity, even transforming a tail into a leg if transplanted. Understanding these diverse regenerative capacities is a central goal of regenerative medicine, which aims to restore tissue and organ integrity. A key figure in this field, Michael Levin of Tufts University, focuses on the concept that biological information is encoded not only in DNA but also in a “bioelectrical code”—electrical signals guiding cell behavior and organ formation.
Levin’s research reveals that cells communicate through bioelectrical signals, akin to software running on genetic hardware, enabling the body to self-correct and regenerate. Experiments with organisms like tadpoles and planarians demonstrate that altering bioelectrical states—without changing the genome—can induce new developmental patterns, such as two-headed worms or misplaced eyes. This suggests a rewritable bioelectrical “memory” controlling regeneration. The implications for medicine are profound: harnessing this physiological software could enable the construction of complex organs and treatments for birth defects, degenerative diseases, injuries, and cancer by directing cells to build desired structures. While some skepticism remains, exploring this bioelectrical approach offers promising new avenues for regenerative therapies and biomedical innovation.
Scientist Michael Levin has carried out pioneering research showing that changes in the shape and function of organisms can be induced with a very promising impact on medicine.
In biology we speak of regeneration when it is possible to restore the structural or physiological integrity of tissues, organs or parts of the body of an individual previously damaged or removed. The animal kingdom is full of examples: axolotls, a Mexican salamander, are capable of regenerating up to five consecutive times completely amputated limbs and organs. Deer can regenerate the bone tissue that forms their antlers, the branched appendages of their heads that molt periodically after the breeding season.
In humans, the liver is an organ that can grow back after an injury. The skin and its appendages such as nails and hair are constantly renewed and repaired. And children can regenerate their fingertips if the injury occurs within the first 7 to 11 years of life. Similarly, frogs can regenerate their tails and limbs when they are in the tadpole stage, but not in adulthood. Salamanders, on the other hand, can not only regenerate limbs and tails if they are amputated, but, if a leg is removed and then the tail is inserted instead of the leg, the tail becomes a leg.
Understanding the reasons for the extreme variability of these phenomena is one of the goals of regenerative medicine, the branch that studies ways to restore the integrity of tissues and organs. The knowledge of these mechanisms, in fact, offers very interesting perspectives and one of the leading experts in this field is the Russian biologist Michael Levin, Professor of Biology, Distinguished Professor of the Faculty of Philosophy and Letters and Professor of Biomedical Engineering at Tufts University, in Massachusetts, USA. Professor Levin participated in the Future Trends Forum dedicated to Neurotechnology, organised by the Bankinter Innovation Foundation.
The importance of the bioelectrical code
Their work is based on the assumption that information about the human body is not only contained in DNA, but is also written into the bioelectrical code that guides cells in building organs. By decoding it, we could induce changes in the form and function of organisms, and medicine could find new ways to treat numerous diseases, including cancer.
Some experiments conducted a few years ago by Levin’s research group yielded surprising results. By haphazardly and abnormally rearranging the body parts of tadpoles (jaw on one side, eyes higher, nostrils on the other side: Levin and his colleagues call them “Picasso frogs”), the animals eventually became frogs with near-normal faces. This would show that there is a system that is not just a set of programmed movements but is capable of “reducing the error between what is happening and what it knows to be a correct configuration of a frog’s face”, explained Levin. A decision-making process that involves flexible responses to new circumstances, i.e. an entirely plausible definition of ‘intelligence’.
The idea is that not only the cells of the nervous system, but all the cells of the body communicate with each other using electrical signals, as evidenced by the electrical states detectable in the first hours of development of frog embryos. “Basically, the cells communicate with each other: who will be the head, who will be the tail, who will be the eyes and the brain, etc.,” Levin said. It’s as if bioelectricity is the software that runs on the cellular hardware defined by the genome. And it’s this software that allows living systems to complete specific goals, such as regenerating a limb.
Modifying the development of organisms without intervening in the genome
Understanding the ‘language’ based on these bioelectrical signals would give us access to the mechanisms of development of organisms. Consequently, by activating certain stimuli – but without the need to intervene in the genome, that is, in the ‘hardware’ – cells could be induced to do something completely different from what they would have done according to the original pattern. In other words, we could harness their collective intelligence and target it for specific needs.
Among the biologist’s best-known studies are some based on a series of experiments with planarians, a genus of highly regenerative flatworms. When planarians divide into two parts, they grow a new severed head tail and a new severed tail head. The researchers obtained 279 pieces of a single planaria, from which as many worms were formed, because each piece knows which part is missing and reconstructs it. By manipulating some tiny valves present in cell membranes (ion channels, proteins that cross the membrane and control the flow of ions in and out of the cell), the scientists induced the formation of two heads in an intermediate piece of planaria, which would otherwise have been destined to form a head and tail.
What they did was to vary the electrical potential of the piece of planaria, without applying electricity or modifying the genome. They achieved this by intervening the same bioelectrical system used by cells as a kind of intercellular internet. By intervening in the proteins in ion channels, Levin explained, it’s as if they had “turned on and off little transistors that each cell uses natively to establish this electrical state.” In the same way it is possible to activate or deactivate a different ‘electric map’ that leads to the formation of two heads and no tail.
The Prospects for Medicine
The most surprising part of these experiments is that by redividing these two-headed worms, more two-headed worms were generated. Therefore, they did not recover a kind of default genomic sequence, capable of reproducing a worm with a head and tail, but “the memory of the model according to which these animals regenerated after having suffered damage was rewritten in a permanent way,” Levin said.
This would show that the information about how these worms should regenerate is not in the genome but in an “additional bioelectrical layer” that can be rewritten without resorting to gene editing. Also applied to tadpoles, this method allowed the formation of perfectly functional organs in different places (an eye in the stomach area) than those expected in normal development.
To modify the pre-established targets at the bioelectrical level and achieve new ones, the scientist said that “we don’t need to know how to make a whole eye, nor worry about controlling the dimensions and getting exactly the right number of cells, we take advantage of the modularity of top-down control and capacity, very similar to other collective intelligences – such as those of ants and termites. to scale their activity by recruiting neighbors when necessary to achieve specific objectives.”
In the future, according to Levin, a thorough understanding of this ‘physiological software’ of the body based on certain rewritable electrical patterns could lead to the construction of complex organs. This would open up enormous prospects in biomedicine, since “most problems – birth defects, degenerative diseases, ageing, traumatic injuries and even cancer – boil down to one thing: cells are not building what you would like them to build”. Although some scientists are skeptical, while acknowledging the role of electrical impulses in cell development, it is a very promising path. And it is worth trying to walk through it.
