Chinese scientists move closer to bringing cryogenically frozen people back to life – after brain tissue thaws without damage

Scientists have come one step closer to preserving our brains forever.

They are among the first to successfully thaw brain tissue that has been cryogenically frozen – without damaging it.

Furthermore, after being frozen, their neurons could still send signals normally.

This has been a major challenge for science because freezing the ultra-sensitive, spongy brains usually damages them, rendering them useless once thawed.

Not only is it a breakthrough for neuroscientists looking to study new drugs, it could also further the sci-fi idea of ​​bringing people back to life in the future.

The idea is that people can freeze their bodies and preserve them indefinitely, in the hope that in the future science will be advanced enough to bring them back to life healthily.

Professor Zhicheng Shao, a Harvard-educated neuroscientist working at Fudan University in Shanghai, China, developed a complex chemical mixture nicknamed MEDY, which protects neurons from damage while they are frozen.

He doesn’t shy 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,” said Dr. Shao in his study, published in the journal Cell report methods.

For a slew of forward-thinking people, from Peter Thiel to Steve Aoki, who rely on their bodies being preserved on ice after death, this should be welcome news.

It’s just that, as Thiel acknowledged in a 2023 interview, we don’t actually know yet how to make cryopreservation work—for the body as a whole and for the brain in particular.

That certainly doesn’t stop companies from taking advantage of the hype. Since the mid-20th century, we have been experiencing a cryo-renaissance, with laboratories in Michigan, Arizona and Australia.

At Michigan-based Cryonics Lab, whole-body preservation starts at $28,000, and their client base has more than tripled since 2006 – now with more than 1,975 permanent residents.

Each cryonics company has its own blend of good properties that they say protects the brain and body, but scientists haven’t yet concluded that there is one surefire way to protect the brain when it freezes.

Because 80 percent of our brain cells are made of water, ice crystals sometimes form when we freeze them.

These can deform and damage all our cells, but especially vulnerable brain cells, making them functionally unusable after thawing.

So Professor Shao and his team set out to find another substance to immerse brain tissue in that would keep it cold and prevent aging, without causing problems with crystals.

You could think of it as adding antifreeze to the water circulating around your car’s engine, keeping it cool without freezing.

To do this, Professor Shao and his team grew small groups of brain cells in petri dishes for three weeks – until they acquired the functions you would see in a normal brain, only in miniature form.

They then soaked these tiny brains, called organoids, in various mixtures, including sugar, antifreeze and chemical solvents.

After the samples were saturated, they were flash frozen with liquid nitrogen and then thawed over the next two weeks.

As the samples thawed, the scientists watched to see which samples recovered with the least damage.

After some trial and error, they came up with a mixture they call MEDY – because of its four ingredients: methylcellulose, ethylene glycol, DMSO and Y27632 – that allows them to freeze the tissue without any damage.

Not only did the brain tissue emerge undamaged, but it also came back to life and was able to function normally again.

In the future, if we want to learn how to do this with the whole body, we need to be able to heal what originally killed a person and reverse aging. Dennis Kowalski, the president of the Cryonics Institute, told Discover Magazine.

Dr. Kowalksi, a self-described optimist, acknowledged that this is clearly “100 percent not possible” today.

Professor Shao’s mixture is not the first substance to successfully protect the brain before it is frozen. Other freezing processes have shown promise, but come with their own problems.

A popular method, which has been hugely successful with pig brains, involves pumping embalming fluid into the brain while a person is still alive. This not only kills the subject, but makes it impossible to revive the brain later, says neuroscientist Dr. Ken Hayworth of the Brain Preservation Foundation. told CNET.

“It glues together all the proteins in the brain almost instantly,” Dr. Hayworth said.

In the near future, Professor Shao wrote that the MEDY technique is likely to be useful for the laboratory alone, Professor Shao wrote.

But we can do a lot with frozen brains in a laboratory.

Being able to freeze these mini-human brains means that much more tissue will be available for researchers to test new drugs and therapies on, Professor Shao wrote.

This could help us make breakthroughs in some stubborn areas of medicine, Dr. Takanori Takebe, a pediatrician at Cincinnati Children’s Hospital Medical Center, said in a 2018 article.

“Organoids hold great promise to revolutionize 21st century healthcare by transforming drug development, precision medicine and ultimately transplant-based therapies for end-stage diseases,” said Dr. Takanori Takebe, a pediatrician from Cincinnati Children’s Hospital Medical Center, said in a 2018 article.

In the more distant future, Professor Shao wrote that MEDY has the potential to freeze the entire brain. But that comes with its own challenges, because the transition from freezing an organoid to an entire organ, such as the brain, is complicated for a number of reasons.

Organoid research in general is a great way to understand how certain cell types work.

But it’s not always effective at predicting how an entire organ would respond to new stimuli, because what’s in the dish is a lot less complex than what’s in our bodies, say researchers at the Eli and Edythe Broad Center of Regeneration Medicine at the University of California wrote in 2023.

Furthermore, the University of California researchers wrote that these organoids simply “do not reflect the full composition, organization, or function of the human brain.” So it’s hard to know whether the way we freeze the organoid will translate to the whole brain.

And even if we can successfully freeze a brain without damaging it, there will be a whole new set of challenges in thawing and resuscitating it because we currently understand so little about the brain, says Dr. Ken Miller, a theoretical neuroscientist at Columbia University. , told CNET.

‘The most fundamental answer to the question of how the brain works is: we don’t know. We know how many parts work…but we are still a long way from understanding the system,” Dr. Miller said.