Blood Of Younger Mice Reverses Aging In Older Mice
May 5, 2014

Could The Fountain Of Youth Be Hidden In Our Blood?

redOrbit Staff & Wire Reports - Your Universe Online

The concept of infusing young blood into a company, sports team or organization was never intended to be taken literally, but three new studies suggest that doing so could actually help to reverse the aging process.

According to Meeri Kim of the Washington Post, adding the blood of young three month old mice into the circulatory systems of elderly 18 month old ones appeared to dramatically improve the muscles and brain of the older rodent.

The researchers combined the creatures’ blood circulations by conjoining them, Kim explained. Four weeks later, they found increased activity in the muscles and brain of the older mice, improving their ability to produce new neurons and muscle tissue. Later, they found that giving transfusions of young blood (or alternately receiving a plasma injection) provided the same benefits as the shared blood supply.

In Sunday’s edition of journal Nature Medicine, a team of biologists led by Tony Wyss-Coray of Stanford University and Saul Villeda of the University of California San Francisco (UCSF) explained that after receiving the young blood, the old mice experienced a noteworthy improvement in navigating a “water maze” and learning to associate a specific area with an electric shock.

“Examining the brains of aged mice exposed to young blood, the scientists found both structural and molecular differences from regular old brains,” said Reuters reporter Sharon Begley. “The treated brains had more ‘dendritic spines’, structures on neurons through which one communicates with another.”

Furthermore, the research team discovered the brains of the older rodents were able to produce a greater amount of a specific molecule that increases during the learning process. They also demonstrated an increased ability to strengthen neuron connections, which are essential for memory and learning functions, Begley said.

“We've shown that at least some age-related impairments in brain function are reversible,” Villeda said. While he and his colleagues said that they weren’t certain what part of the blood has this “fountain of youth” effect, the authors of two forthcoming research papers might have identified the source – a growth factor known as GDF-11.

Two teams of researchers led by Harvard University Department of Stem Cell and Regenerative Biology (HSCRB) professors Dr. Amy Wagers and Dr. Lee Rubin, explained that GDF11 (which is present in humans as well as mice) enhanced the exercise capability of a mouse roughly equivalent in age to a 70-year-old person. Furthermore, it also improved the olfactory region of their brains, allowing them to sense odors as well as younger rodents.

Their studies, which will be published Friday by the journal Science, examined the effects of this growth factor in two ways similar to those used by Wyss-Coray and Villeda. First, they used a parabiotic system to surgically join the mice and allow the blood of the younger mouse to run through the system of the older one, and second, they injected the older mice with GDF11.

As in the Wyss-Coray and Villeda study, the Harvard researchers found that the blood of the younger mice improved the brain and skeletal muscle function of the older ones. Barring unexpected developments, Dr. Wagers and Dr. Rubin believe they will be able to launch initial human clinical trials for GDF11 within the next three to five years, the university said in a statement Sunday.

According to Carl Zimmer of the New York Times, the similar methods and results of the respective research teams has led medical experts to express confidence that their conclusions are accurate. Richard M. Ransohoff, director of the Neuroinflammation Research Center at the Cleveland Clinic, told Zimmer that the lack of conflict between the authors was “heartening.”

However, while the process could revitalize failing organs and tissues, some scientists warn that it could also result in unintended side effects, Zimmer said. Awakening stem cells could cause them to multiply uncontrollably, he said, and University of California, Berkeley bioengineering professor Irina M. Conboy added that this could “dramatically increase the incidence of cancer.”