Aging is inevitable, but one of the keys to mitigating the physical decline that comes with growing older may be found in blood. A team led by bioengineers Irina Conboy and Michael Conboy has found that diluting the blood plasma of older mice has rejuvenating effects on the body. In the study, the researchers replaced half of the blood plasma of mice with a saline solution containing 5% albumin, which simply replaced protein lost when the original blood plasma was removed but did not have young or old properties on its own. In doing so, they observed improved function of the brain, liver and muscle in the older mice; performing the same procedure on young mice had no detrimental effects on their health.
This discovery establishes the benefits of removing age-elevated, and potentially harmful, factors in old blood — opening the door to new therapies in humans. Currently, the composition of human blood plasma can be altered through therapeutic plasma exchange, or plasmapheresis, which is used to treat a variety of autoimmune diseases. The research team is now working to develop a modified plasma exchange that could be used to improve the overall health of older people and not only treat but also prevent age-associated diseases in humans.