US scientists discover diluted blood plasma can reverse ill-effects of aging in mice
New research into the aging process has revealed how diluting the blood plasma of older mice can have a strong rejuvenation effect on tissues and organs, thanks to bioengineers at the University of California-Berkeley (UC-Berkeley), led by Irina and Michael Conboy. The scientists believe that reducing the concentration of inflammatory proteins that typically increase with age could reverse some of the effects of aging – perhaps the process of aging could be slowed by cleansing the old blood of its harmful proteins and molecules.
In a neutral blood exchange experiment, part of the animal’s blood was substituted for a special solution made of basic ingredients in saline and the protein albumin, which replaces the lost albumin proteins in the extracted blood. The scientists noted significantly improved health markers when half of the blood plasma in older mice was swapped out for the solution, such as lower concentrations of pro-inflammatory proteins, while beneficial proteins including those that promote vascularisation, where able to flourish. The procedure was also found to have no ill health effects on younger mice.
“We thought, ‘What if we had some neutral age blood, some blood that was not young or not old?’” said Michael Conboy. “We’ll do the exchange with that, and see if it still improves the old animal. That would mean that by diluting the bad stuff in the old blood, it made the animal better. And if the young animal got worse, then that would mean that that diluting the good stuff in the young animal made the young animal worse.”
After proteomic analysis to study the blood plasma and its contents of proteins, the neutral blood exchange was concluded to act like a “molecular reset button” with rejuvenation effects on the brain, liver and muscles similar to or stronger than a past experiment with young/old mice. (Irina and Michael experimented on conjoined twins of old and young mice with shared blood and organs, nearly 15 years ago. The proteins and molecules that were contained in the younger mouse’s blood were thought to function as a “fountain of youth” that could possibly slow or reverse aging in the older animal.)
The exchange of plasma in humans is already approved in the US for treatment of some autoimmune diseases, as it is quick and produces mild or zero side effects. The scientists are now in the process of drawing up clinical trials to explore the potential of neutral blood exchanges in older people.
However, Michael Conboy warns against silver bullets, “It is very unlikely that aging could be reversed by changes in any one protein. In our experiment, we found that we can do one procedure that is relatively simple and FDA-approved, yet it simultaneously changed levels of numerous proteins in the right direction.”