Young mouse blood may be the key to the fountain of youth. Although this sentence might seem straight out of the pages of a novel by Bram Stoker, creator of Dracula, it is the conclusion of articles published today by "Science"and "Nature Medicine," two of the most prestigious scientific journals. Something in the blood of young mice is able to rejuvenate muscle and brains of mice who are in the last stage of their lives, if you consider that a mouse usually does not live beyond two years on average. Conversely, blood from old mice hurts younger mice.
This actually is not new and it was first known through experiments that link the circulatory systems of two rodents. This surgical procedure is called parabiosis and was described over half a century ago. But now, recent investigations have taken a step that could have important therapeutic implications. The work published in "Nature Medicine" suggests that a blood protein capable of launching cascades of cellular processes may just be the fountain of youth. With the seal of the prestigious Stanford University, researchers have found that "something" in the blood of young mice can restore mental abilities in old mice.
If that "something" also would work in humans, it would be a new way to treat diseases like Alzheimer's. Regarding the young mouse blood study, The Associated Press wrote that two other papers, from Harvard University, focused on a substance that is more abundant in the blood of younger mice than old. That protein, called GDF11, is also found in human blood and its concentration also appears to decline with age, said Amy Wagers, an author on both papers.
These functional changes in old mice are supported by structural changes, particularly the hippocampus, involved in memory and learning. The injection of young mouse blood gave older mice an increased number of dendritic spines, small "door knob" shaped extensions that facilitate contact between neurons, and therefore learning.
The New York Times reports that in the 1950s, Clive M. McCay of Cornell University and his colleagues tested the implications of young blood by delivering the blood of young rats into old ones. To do so, they joined rats in pairs by stitching together the skin on their flanks. After this procedure, called parabiosis, blood vessels grew and joined the rats’ circulatory systems. The blood from the young rat flowed into the old one, and vice versa.
The young mouse blood study, led by Tony Wyss-Coray, shows that, in rodents, at least some of the damaging effects of aging are reversible. "Their fur looks better, they groom better, they seem to do overall better," Wyss-Coray said. "To us it's just so surprising, that something so simple has dramatic effects on every tissue in the body that's been looked at."