Is brain transplant at all possible? Wonderful story about a rodent maverick that changed the way we understood neuroscience.
Sleep is a criminal waste of time
Well, at least that’s what one famous inventor, Thomas Edison, said about this very interesting activity. We spend about a third of our time sleeping, which is an average of 25 years during lifetime.
25 bloody years doing exactly nothing.
But is it really a time wasted? I could write a whole article on that matter, explaining why we know almost nothing about the Morpheus’ state of the body. Today, however, for the sake of neuroscientists sanity (if such thing at all exists), we’ll stick to the things we know.
Circadian rhythm masterclock
Think about how you feel right now. You may be overexcited by the notion of knowing how a cute little animal showed big grumpy scientists their place in the row, but got a little bit irritated that I have not revealed it yet.
Perhaps you simply try to not fall asleep in work and read this article, whilst simultaneously looking for some funny cat pictures.
In fact, there’s a little thing* in your mind that tells you when you feel tired and sleepy, and when’s the time to wake up and feel wonderful. This biorhythm of your life (circadian is a fancy word that scientists use to sound smart) is slightly different for every person and may be influenced by many factors.
Light, that delicious double espresso or eight shots of tequila your mate said you wouldn’t drink.
All have their impact on your body clock. And — it turns out that hamsters are masterful in keeping it right all the time. They can run on almost perfectly timed schedules for weeks!
*it’s called Suprachiasmatic Nucleus (SCN) for short (cool name, isn’t it?)
All but one
Martin Ralph and Michael Menaker (Oregon, USA) noticed that one day, a hamster began punching in with 22.0-hour cycles instead of normal 24h-ish cycles.
What they did with this observation? They found our little friend a girlfriend. Actually, three of them.
All three hamster ladies were perfectly normal (at least in terms of their circadian rhythms), and quickly spotted the opportunity of having little cure hamsters babies with the rodent freak.
Their offspring was split 50/50, i.e. half of the tiny creatures had strange sleeping habits, whereas the other 50% were perfectly normal. Those who remember some of their biology GCSE will spot that something is going on here…
Yep, it turned out that the biological clocks (and their mutated state) are almost perfectly reflected by the Mendelian pattern of inheritance.
Brain transplant that worked. Sort of.
After a couple of more experiments, involving ablation of the SCN (that is, they literally put a laser rod inside and burnt it off) they worked out that these rhythms went entirely off the hook.
The brave hamsteroneurosurgeons performed an SCN transplant from other hamster and… achieved full recovery of function. Which meant not only that this part of the brain is crucial for regulation of day/night cycle, but also that you can transplant it and it will work!
The experiment wasn’t that lucky for the other hamster, though.
FUN FACT: Although your SCN is mainly driven by light, blind people can still see the light and get the rhythms correctly, even though they can’t actually see that light. But that’s a topic for another story.
Is brain transplant possible?
I’m going to leave the ethics out of this article, although even the prospective thought of preforming a brain transplant would cause a stir in the minds of almost every person, let alone the ethics committee.
The whole idea was vivid in the 70s and 80s, but people were going quite scalpel happy these days, so the amount of research declined since ethics began to really matter in scientific world.
- Nevertheless, there is statistically significant improvement of function in many cases: we have seen remyelination, neuroprotection and better signalling of neurons.
- There are papers on how this method could improve or even treat diseases like Parkinson’s, Alzheimer’s or Huntington’s.
- Models and protocols for prospective procedure have been developed, and the technology of neuroimaging and precision of neurosurgery make the whole idea even more plausible today than it was in 1970s.
I promised I won’t go into ethics, but really — we actually need a brain to be transplanted, so someone has to… well, DIE. Not even mentioning the danger of dealing with such a fragile organ and preserving it from damage.
- There are no randomised controlled trials that show that any of the methods proposed will actually work
- The research was mainly performed on rats and in vitro, and I think I don’t have to point out that what happens in the dish on the lab bench does not necessarily reflect an adult human being.
- It would incur massive costs and safety concerns are almost endless. TheDBS technique is safer than that, and when I say that something is safer than the DBS, you may imagine the level of its dangers.
So… it’s a no brainier, then?
Forgive my joke, but I couldn’t resist it. Anyway, the idea of transplanting the brain will stay in the Sci-Fi area (where it belongs, really).
However, I wouldn’t strike it off completely just yet.
With the advent of stem cell research, more information about the neurogenesis and tissue preservation, we may soon be able to produce a part of the brain the patient needs, using their own stem cells.
That may seem far fetched, but it actually works as we speak. Cancer antibodies, immunology factors and even whole vertebrae are produced in the labs, with extraordinary techniques and positive early trial results.
If we can produce an antibody to treat terminal cancer, why can’t we producea replacement nucleus for Alzheimer’s patients?
You may call me a dreamer, but my money is on that happening during our lifetime.
Do you agree with me? I tried to keep this article as unsciency as possible, if you want to have a proper nerdy conversation about it, you know, with references and stuff, drop me a line.