What If Humans Could Regenerate? | Unveiled

What if Humans Could Regenerate?

The older we humans get, the more wounds and scars we tend to accumulate just by merit of being alive and making our way through the world. Some injuries are clearly more serious or life-changing than others but all bumps, scrapes and accidents to some degree change or challenge our bodies. But, will it always be this way? This is Unveiled, and today we’re answering the extraordinary question; What if humans could regenerate? Fiction is full of superpowered or inhuman characters who possess incredible healing abilities. Since the 1960s, the BBC’s “Doctor Who” has ruled the roost of regeneration legend, with its iconic Time Lord changing their face and body every time the lead actor retires - usually via a chaotic process using lots of mystical “regeneration energy”. But while “Doctor Who” is probably the example most synonymous with the terminology, there are plenty of other heroes who are also extreme healers. Wolverine has his adamantium skeleton and super-speedy recovery times; Deadpool can heal from any ailment and even regrow limbs; and the Flash’s speedster metabolism means he’s never off his feet for long… Then, in a time even further back than comic books and TV shows we had mythological figures; like the serpentine Hydra which regrows two heads for every one chopped off, and the Titan Prometheus who regrows his entire liver every night after having it pecked out by an eagle. And amazingly, in the real world, regeneration isn’t actually as fantastical as these examples may lead us to believe. It’s a prevalent trait in the animal kingdom, possessed by all sorts of creatures from salamanders to flatworms to starfish. Lobsters, too, can regrow their claws and legs. There’s even a creature, the potentially immortal jellyfish “Turritopsis dohrnii”, which is capable of forcing its own cells to regress to a younger state if it suffers enough damage - it can start its entire life cycle all over again. So, it’s not completely ludicrous to imagine humans reaching a similar point one day in the future, either through evolution or technological advancement. Though, it’s also important to note that many “regenerating animals” like flatworms and jellyfish aren’t particularly complex in other ways; starfish might be able to regrow their lost arms, for example, but they don’t even have brains… so converting their skill into a human ability would definitely be tricky. That isn’t to say that humans aren’t already good healers just because we can’t grow back entire limbs, however. Humans are actually incredibly robust lifeforms, capable of at least potentially overcoming a variety of injuries and diseases thanks not just to our biology but also to our intelligence and ability to develop medicine. But even without medicine, some parts of our bodies possess extensive regenerative abilities, most famously the liver which, in some cases, can repair itself following alcohol abuse. Liver recovery is by no means a given, but it is arguably the hardiest of all human organs… while human skin is also a good healer as it is, often recovering from smaller wounds without leaving any sign of scar tissue. We’ve even seen cases of lost fingertips effectively being “re-grown”. But of course, regeneration differs from simple, standard healing because the tissue in sci-fi-style regeneration is brand new. It’s not scar tissue covering an injury, it’s fresh, never-before-used cells and flesh. Even here, though, we do already have a starting point. The human body actually regenerates most of its cells every seven to ten years (depending on what type of cells they are). Although, this obviously doesn’t imbue us with everlasting youth… Some scientists think this is because ageing is part of our DNA, which is contained in every cell… and, because our DNA is the same from birth, we (and our DNA) get older despite our cells getting newer. In this way though, it’s true to say that you’re actually regenerating right now as you watch this video! More seriously, faster regenerative healing is a major focus of modern medicine and has already been demonstrated a few times. Certain body parts have been regrown in labs, drugs have been used to force cells to heal, and stem cell research continues to uncover other possibilities. While the use of stem cells is controversial because researchers and doctors often get them from terminated or non-viable human embryos, they do possess the unique ability to become any other type of cell - which could also be vital in the battle against some conditions and diseases. Adults also have stem cells, though, usually found in bone marrow, and some experiments to convert adult stem cells to have the same properties as embryonic stem cells have been successful… all of which bodes well for potential human regeneration. Though again not without their controversies, animal experiments have also made progress… For example, scientists have successfully led African clawed frogs to regrow amputated limbs after treating the injury with a compound made from progesterone, a female sex hormone. While tadpoles have displayed the ability to regrow their tails, which has led to early speculation that human embryos might be able to do the same thing with limbs. However, one of the big concerns in human regenerative medicine is how to get the cells to stop growing once a new limb, or a new anything else, has successfully formed. If new cells don’t stop growing, rather than uncovering a ground-breaking method of healing, we might have actually discovered a way to artificially induce cancer, which nobody wants. In the frog experiment, though, the frog legs did stop growing after a few months, and the test animals were ultimately indistinguishable from other frogs whose legs hadn’t been amputated. While further experiments on mice have shown that it might just be a single gene - the p21 gene - that’s responsible for preventing humans from regenerating in the first place. Lab mice bred without this gene have reportedly shown superior healing powers, which could mean that the same would be true of humans. However, proposed removal of the p21 gene has similar controversies surrounding it… with many suspecting that it’s actually responsible for mitigating cancer, meaning we’d potentially again be more likely to develop cancers without p21 to keep us in check. As has become clear in recent years, there’s a very fine balance here, between an incredible medical breakthrough and a deadly human disaster. All things considered, it does look like regenerative medicine of some description is on the horizon. So, if – or when – we finally get it, what effect might it have on the world? Well, for a start, regenerative medicine isn’t really a route to immortality. All animals already capable of regenerating do eventually die, even the “potentially” immortal jellyfish, which only regenerates when wounded and won’t “start again” if it reaches the end of its life naturally. Similarly, the axolotl can regenerate almost any part of its body, but it still only has a life expectancy of 15 years. As for flatworms, they’re able to regrow their heads and brains, but often live for only a matter of weeks. Again, regeneration as we know it doesn’t reset DNA, so it doesn’t reverse or “beat” the ageing process. Clearly though, just because we wouldn’t become immortal doesn’t mean that regenerative medicine isn’t worthwhile. It would surely still increase our life expectancy and our general quality of life once we get old. With regen treatments across the board, we’d no longer find ourselves felled by injury. Instead, we’d be capable of overcoming all that life could throw at us, leaving us only at the mercy of how quickly our bodies age. Naturally, the most visible result of regenerative therapy would be people with missing limbs being able to regrow their body parts, but even some seemingly unrelated ailments would be a thing of the past. Alzheimer’s disease, for instance, happens when a build-up of certain proteins in the brain starts to damage nerve cells; but regenerative medicine could repair the damage that Alzheimer’s does to those cells, reversing and potentially even curing it! Lung and heart disease, both common causes of death, could also be stopped if damaged organ tissue can be fully repaired. Our physical journeys through life in general would throw up much less cause for concern were treatments like these efficient and widely available. With less injury, sickness and stress over our health, people would live longer, better and happier lives. The ailments that come hand-in-hand with “being alive” would be mere bumps in the road; temporary problems that are easy to fix. And that’s what would happen if humans could regenerate.