Young Blood can Rejuvenate Brains of Old Mice; Stanford Study Finds

Infusion of young blood can rejuvenate brains of old mice, a new study from Stanford found.

Researchers at Stanford University School of Medicine have found that certain proteins in young blood can reverse some signs of old age in mice.

People across several cultures believe that blood, the life force, can cure illnesses. It is rumored that North Korea's leader Kim Jong-il would inject himself with blood of young virgins in a bid to stay young and healthy.

The latest study backs the idea that blood can be good for the brain, at least in mice. The discovery could lead to a paradigm shift in Alzheimer's disease research.

The current research is an extension of a 2011 paper published in Nature. That paper by Wyss-Coray and team had showed that certain brain regions in old mice exposed to young blood produced new nerve cells.

For the present study, researchers conducted experiments on sets of mice called parabionts. These mice had their circulatory systems stitched together, making them function like conjoined twins. In one set of the parabionts, both mice were old whereas in the other set, one mouse was young while the other was old. Researchers then let these mice share the blood for about five weeks. The team then examined mice brains and genes, Discover magazine reports.

The team found that older mice paired with young mice had altered brain function. In particular, the hippocampus, a region associated with learning and memory, showed greater flexibility and had better signaling pathways. Old mice paired with other mice of same age had no such differences in brain activity.

"It was as if these old brains were recharged by young blood," Tony Wyss-Coray, one of the study authors said.

In another set of experiments, researchers found that old mice injected with blood plasma of young mice did better on memory and learning tasks than mice injected with old mice blood.

According to the research team, the effect of the blood transfusion vanished if it was subjected to heat before being injected. Proteins break down at high temperature. So, researchers believe that it is either one or a group of proteins that is responsible for the increase in cognitive ability in old mice.

"There are factors present in blood from young mice that can recharge an old mouse's brain so that it functions more like a younger one," Wyss-Coray said in a news release. "We're working intensively to find out what those factors might be and from exactly which tissues they originate."

"We don't know yet if this will work in humans," he added.

The study is published in the journal Nature Medicine. It was funded by U.S. Department of Veteran Affairs, the California Institute for Regenerative Medicine and the National Institute of Aging.

Wyss-Coray is a co-founder of biotechnology company, Alkahest. He and his team will be exploring the therapeutic applications of the new study findings.