Scientists have moved a step closer to preserving our brains forever.
They are one of the first to successfully thaw brain tissue that has been cryogenically frozen – without damaging it.
Further, after being frozen, their neurons were still able to send signals as normal.
This has been a major challenge for science, because freezing the ultra-delicate, spongy brain usually damages it, making it useless when it’s thawed.
Not only is it a breakthrough for neuroscientists looking to study new drugs, it could also advance the sci-fi idea of bringing people back to life in the future.
Many celebrities have said they hope to freeze their bodies when they die, in case they’re able to reanimate their brains in the future.
The longest-running patient at Cryonics Institute, named Rhea Ettinger, has been there since 1977. The amount of people stored at the Michigan institution has more than tripled since 2006.
The idea is that people could freeze their bodies, preserving them indefinitely, in hopes that in the future, science will be advanced enough to bring them back to life, healthy.
Professor Zhicheng Shao, a Harvard trained neuroscientist who works at Fudan University in Shanghai China, developed a complex chemical mixture nicknamed MEDY which protects neurons from being damaged while frozen.
He is not shying away from the idea that the research could be used for cryonics, which has been a fantasy among futurists for decades.
‘MEDY could be used for the cryopreservation of human brain tissue,’ Dr Shao said in his study, published in the journal Cell Reports Methods.
For a range of future-minded people, from the likes of Peter Thiel to Steve Aoki, who are banking on preserving their bodies in ice after they die, this should be welcome news.
It’s just that, like Thiel acknowledged in a 2023 interview, we don’t actually know how to make cryopreservation work yet- for the body at large and the brain in particular.
That certainly hasn’t stopped businesses from cashing in on the hype. Since the mid 20th century we’ve been enjoying cryo-renaissance, with labs springing up in Michigan, Arizona and Australia.
At Michigan based Cryonics Lab, the full-body preservation starts at $28,000, and their clientele has more than tripled since 2006 – now boasting more than 1,975 permanent residents.
Each cryonic business has their own propriety mixture that they say is preserving the brain and bodies, but scientists haven’t concluded there’s one surefire way to protect the brain when it freezes.
Since 80 percent of our brain cells are made of water, when we freeze them, sometimes ice crystals form.
These can distort and damage all of our cells, but especially delicate brain cells- making them functionally useless when thawed.
So Professor Shao and his team set out to look for a different substance to submerge brain tissue in that kept it cold- stopping it form aging – without running into issues with crystals.
You could think of it like adding antifreeze to the water that circulates around your car engine – which keeps it cool without freezing.
To do this, Professor Shao and his team grew small clumps of brain cells in petri dishes for three weeks – until they gained the functions that you’d see in a normal brain, just in miniature form.
Then they soaked these tiny brains, called organoids, in different mixtures, including sugar, antifreeze and chemical solvents.
After the samples were saturated, they were flash frozen with liquid nitrogen and then allowed to thaw over the next two weeks.
As the samples thawed, the scientists watched to see which samples recovered with the least amount of damage.
The tiny organoid – approximately the size of a lentil – was made of connected human brain cells for a study in 2019.
A cryonics facility located next to the Holbrook cemetery, in New South Wales Australia. Spots in this freezer down-under cost around $150,000.
Because the brain is made of 80 percent water, freezing it can make ice crystals form in the tissue, which damages the cells and makes them unfunctional when they thaw.
After some trial and error, they concocted a mixture they call MEDY – for its four ingredients: methylcellulose, ethylene glycol, DMSO, and Y27632 – which allows them to freeze the tissue without any damage.
Not only did the brain tissue come out undamaged, but it also came back to life, able to regain normal function.
In the future, if we wanted to learn how to do this with the whole body, we’d have to be able to be able to cure whatever killed a person originally, and reverse aging, Dennis Kowalski, the president of the Cryonics Institute, told Discover Magazine.
Dr Kowalksi, a self-described optimist, acknowledged that this clearly, ‘100 percent not possible today.’
Professor Shao’s mixture isn’t the first substance that has successfully protected a brain before it’s frozen. Other freezing processes have shown promise, but come with their own set of issues.
One popular method, which was wildly successful in pig brains, involves pumping embalming fluid into the brain while someone is still living. This not only kills the subject, but makes it impossible to revive the brain later, neuroscientist Dr Ken Hayworth, from the Brain Preservation Foundation, told CNET.
‘It almost instantly glues together all the proteins in the brain,’ Dr Hayworth said.
In the near future, Professor Shao wrote that the MEDY technique is likely useful for the lab alone, Professor Shao wrote.
But there’s a lot we can do with frozen brains in a lab.
Being able to freeze these mini human brains means that way more tissue will be available for researchers to test new drugs and therapies on, Professor Shao wrote.
This could help us make breakthroughs in a number of stubborn areas of medicine, Dr Takanori Takebe a pediatrician from the Cincinnati Children’s Hospital Medical Center, said in a 2018 paper.
‘Organoids hold great promise to revolutionize 21st century healthcare through transforming drug development, precision medicine, and ultimately, transplantation-based therapies for end-stage diseases,’ Dr Takanori Takebe a pediatrician from the Cincinnati Children’s Hospital Medical Center, said in a 2018 paper.
In the more distant future, Professor Shao wrote that MEDY has potential for freezing the whole brain. But that comes with it’s own set of challenges, because moving from freezing an organoid to a whole organ, like the brain, is complicated for a number of reasons.
Organoid research, in general, is a great way to understand how certain cell types act.
But it isn’t always effective at predicting how a whole organ would respond to new stimuli, since what’s in the dish is a lot less complex than what’s in our bodies, researchers from the Eli and Edythe Broad Center of Regeneration Medicine at the University of California wrote in 2023.
Further, the University of California researchers wrote, these organoids simply, ‘do not reflect the entirety of human brain composition, organization, or function.’ So it’s difficult to know if how we freeze the organoid will translate to the whole brain.
Also, even if we can successfully freeze a brain without damaging it, there will be a whole new set of challenges to thawing it and reanimating, because there’s so little we currently understand about the brain, Dr Ken Miller, a theoretical neuroscientist at Columbia University, told CNET.
‘The most basic answer to how the brain works is, we don’t know. We know how a lot of pieces work … but we’re very far from understanding the system,’ Dr Miller said.