YOUNG BLOOD CAN REJUVENATE THE OLD
The immune system has frequently been used as a model system for aging and rejuvenation studies. The uniqueness of this organ system is that immune cells can easily be removed from the body via a simple blood draw and manipulated in the laboratory and if needed, returned to a patient via a blood infusion. However, blood has many dissolved components (gases, nutrients, waste, and proteins) in addition to the immune cells that have been suspected to play a role in the aging process. Is there evidence that shows if young blood can rejuvenate the old?
10 year old study shows young blood can rejuvenate the old
Nearly ten years ago, a group of scientist from Stanford University fused the blood stream of old and young rodents in an effort to determine if there is something in the blood stream of young rodents that could benefit the old mice’s tissue-specific stem cells (Nature, 2005 vol. 433 page 760). There was. In that early study, investigators discovered that in the old mice muscle regeneration was increased, thinning of the epithelial skin layer was reversed and the bone marrow cell numbers went back to a more youthful level. From this initial study it appeared that young blood can rejuvenate the old if two animals were fused.
All in all, the old mice rejuvenated to a more youthful level. The obvious question that many researchers then asked was: what component(s) in the blood caused this reversal of aging?
This year a new look in to how young blood can rejuvenate the old was done by different universities.
Interestingly, this month of May three independent research groups have now published additional details on this very subject.
Stanford team tries to make young blood can rejuvenate the old
One group from Stanford decided to inject old mice with blood plasma (rather than whole blood) from young mice and test memory function (Nature Medicine, 2014, doi:10.1038/nm.3569). To test cognitive function, old mice treated with plasma were compared to non-treated mice and the researchers observed that plasma treated mice performed better in various cognitive test. The Stanford team clearly showed plasma from young blood can rejuvenate the old when it came to cognition.
Harvard teams examine how young blood can rejuvenate the old
Two other research groups both coming from Harvard University took it a step further. They isolated a compound from the blood that is commonly found in higher levels in young mice (as well as in young humans) when compared to old mice’s blood, called growth differentiation factor 11 or GDF11 (Science, 2014, vol. 344 page 630 and Science, 2014, vol. 344 page 649). For these experiments, the research groups were similar in that they both injected GDF11 into the mice but they were different in the physiological changes they were looking in the mice.
The first group looked at mental deterioration due to a decrease in blood vessels providing nutrients to neurons. They verified their hypothesis by testing the mice’s sense of smell, which normally deteriorates with age. Treating the mice with GDF11 caused the sense of smell to return for the old mice. Demonstrating that the blood vessels, which provide nutrients to neurons, allow neurons to develop even at an old age. In the second paper, the GDF11 treated mice’s muscle cells DNA integrity was checked, as well as, strength and endurance. The two studies again provide evidence that factors in young blood can rejuvenate the old mice in various ways.
In all cases, GDF11 treated mice had better DNA integrity, increased strength and increased endurance.
In animals tested it is apparent that young blood can rejuvenate the old
From these three paper and others before it, there is little doubt now, that at least GDF11 (and possibly other compounds) in the blood can have a wide effect in rejuvenating old mice’s thinking process, sensory function, strength and endurance. It will now be interesting to begin testing in human cells, to determine if the same will hold true for us.
Please do not drink blood
Commentary from Anthony Loera
While we are amazed at some of the results that have had some of us raise our eyebrows and make vampire jokes, the fact is that humans cannot drink blood to because of its iron content. Although the studies in this article show impressive results due to how young blood can rejuvenate the old, we must advise that those people considering drinking blood simply be aware that humans have not developed any iron-extracting mechanisms that would prevent poisoning. We completely advise against such actions. While fictional characters such as immortal Vampires and serial killers like Elizabeth Báthory have provided horror fans much to think about, the fact is that the science has not tested the young blood factors on human beings yet. Strange as it may seem, if human tests are successful, the closest we may ever get to drinking blood factors like a vampire may simply be through an injection or an IV.