Infusing blood from younger creatures into older ones in hopes of halting—or even reversing—the aging process may sound like a macabre scene straight out of “Game of Thrones.” However, several scientific studies have shown that when older animals receive blood from younger counterparts, it improves the function of stem cells throughout the body, boosting tissue regeneration and healing. What’s not been clear is whether this activity can also rejuvenate the brain’s cognitive powers.
Let’s face it: aging is tough on the brain. The number of neural stem cells shrinks, producing fewer neurons; and many of the genes that promote brain development and neural connections become less active. To find out if young blood might hold some of the answers to this complex problem, two teams of NIH-funded researchers—one in Massachusetts and the other in California—recently turned to mice as a model system.
For the West Coast team, led by Saul Villeda of the University of California, San Francisco and Tony Wyss-Coray of Stanford University, the effort began a few years ago with the discovery that when old mice are exposed to blood from young mice, their neural stem cells increase. The opposite was also found to be true: blood from old mice inhibited stem cell proliferation in young brains and hindered certain types of memory and learning .
In their new work, the researchers fused the circulatory systems of young mice (3 months old) with that of old mice (18 months old). The procedure, called parabiosis, created a shared blood supply. As a control, the researchers connected the circulatory systems of old mice.
The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.