Is Parabiosis the Fountain of Youth?

An illustration from the textbook Biology shows an attempted blood transfusion from one person to another in the 19th century. Neveshkin Nikolay/

To what lengths would you go to stay forever young? For vampires, just a sip of human blood is enough to do the trick. And according to some scientists, young blood could potentially work for the rest of us, reports MIT Technology Review.

The hopeful notion that we can turn back the clock and combat aging isn’t new, and the possible anti-aging procedure that's gaining steam isn’t really that new either. The procedure that some think can be used for anti-aging purposes — or at least the regeneration of old and deteriorated tissues — is what’s called parabiosis.

Parabiosis is an experimental surgery that was first utilized in the 1864 by physiologist Paul Bert, according to Nature. Bert sought to conjoin two albino rats — using their skin — to create a shared circulatory system between the two animals. His experiment produced the desired outcome and the two mice’s bodies worked together to pump each other’s blood.

The practice of parabiosis eventually declined over time, but in the past few years, some scientists have revisited the procedure to see how parabiosis might be of benefit to the regeneration of deteriorated tissues in mice — and possibly beyond.

Studies aimed at finding the correlation between parabiosis and aging have led some to wonder whether the infusion of young blood into older individuals could be used to treat symptoms of aging in humans.

Researchers seek the elixir of youth

Hand with veins and arteries isolated on black background
The circulatory system could hold the key to living longer with less symptoms of aging. sruilk/Shutterstock

In 2013, Harvard Stem Cell Institute researcher, Amy Wagers conducted a study that explored the possibilities of parabiosis and anti-aging in mice, reports MIT Technology Review.

For Wagers' study, young mice and old mice were conjoined at the hip to link their circulatory systems to see if the blood of younger mice could serve as a sort of elixir to regenerate dying tissues in the older mice. The experiments were successful, and the elderly mice experienced a regeneration and strengthening of proper heart functioning.

MIT Technology Review reports that in 2014, Wagers conducted two further studies that were published in Science.

Wagers sought to show how the role of the protein growth factor GDF11 plays a part in parabiosis and the restoration of degenerated muscles and brain tissues due to aging. Her first study confirmed that GDF11 improved the muscle strength in older mice. Her second study showed that GDF11 can help restore the effects of the aging brain in mice. Her findings suggest that GDF11 levels decline with age and that the regeneration of GDF11 could play a significant role in combatting certain effects of aging.

It’s important to note though that “We’re not de-aging animals,” Wagers says. “We’re restoring function to tissues.”

... and businesses followed suite

Since the release of Wagers' research, some have attempted to capitalize on Wager’s work for the purpose of combatting the degeneration of tissues in humans. Startup companies such as Ambrosia and Alkahest have already begun clinical trials to see how findings from parabiosis research can make use of blood transfusion to restore and rejuvenate degenerative issues that arise with age.

In 2016, Ambrosia began clinical trials that offer blood transfusions from the young to 600 patients who are age 35 and up and have $8,000 for the procedure. Alkahest’s goal is to see if young blood infusion can be of aid in combatting Alzheimer’s for those who have a predisposition to the disease.

The procedure and evidence is, of course, controversial. There hasn’t been enough time to really see any results, and the research remains inconclusive.

There have been studies conducted by scientists at Novartis that refute Wagers' results. Those studies claim that GDF11 levels actually increase with age. Scientists at GlaxoSmithKline and Five Prime Therapeutics have shown that administering GDF11 doesn’t improve the functioning of muscles in mice with Duchenne Muscular Dystrophy.

So is young blood infusion the way to put the aging process on hold? Like many de-aging remedies, the jury still seems to be out on whether or not the transfusion of young blood into older individuals can actually produce any effect.