Today’s society is obsessed with being young. However, the best option for remaining young appears to be calorie restriction. Problem is few want to do this, and calorie
restriction is not 100% proven to work in humans. Really the best people can do
right now is just cover aging up is by moisturizing, using sunblock,
working out, getting botox or dying our hair.
But, two classic experiments have kept many hopes alive to turning back
the clock someday.
Back in 1989 two scientist, Faulkner and Carlson, at the
University of Michigan performed a muscle graft experiment. Muscle from a young rat was grafted and put
into an old rat. Then vice versa, old rat muscle placed into a young rat. To the scientist surprise the old muscle
grafted into the young rat regenerated much better than the young muscle
grafted into an old mouse. This changed
the idea of aging to focus on the environment of the tissue.
Well, sixteen years later in 2005, Thomas Rando at Stanford University
performed a similar experiment where they changed the systemic environment of
an old mouse. Rando’s lab did this by a cool technique called parabiosis where
two mice's cardiovascular systems are surgically connected together. Rando specific technique used was called Heterchronic Parabiosis (i.e. Different Age
Parabiosis) to assess how a young systemic environment affected an older
animal. He connected the circulatory system of an old mouse to a young mouse. Similar to Faulkner and Carlson’s muscle graft
experiment, the older mice tissue showed a youthful regeneration.
Both of these studies indicate that the blood or the
systemic environment that the tissue baths in plays a key role in the aging
process. While, the age of the tissue seems to have less of an impact. The future of these
experiments could lead to organ regeneration or celebrities like Suzan
Summers getting blood transfusion from babies to roll back the odometer. The world of aging might have cracked the code and it appears the to be something in young blood. Vampires might have had it right this whole time.
Carlson, B. M., Dedkov, E. I., Borisov, A. B., & Faulkner, J. A.
(2001). Skeletal Muscle Regeneration in Very Old Rats. The Journals of
Gerontology Series a: Biological Sciences and Medical Sciences, 56(5),
B224–B233. doi:10.1093/gerona/56.5.B224
Conboy, I.
M., Conboy, M. J., Wagers, A. J., Girma, E. R., Weissman, I. L., & Rando,
T. A. (2005). Rejuvenation of aged progenitor cells by exposure to a young systemic
environment. Nature, 433(7027), 760–764. doi:10.1038/nature03260
That's really interesting! I did a little more research into this and found that several people throughout history believed in this. Pope Innocent VII started receiving transfusions in the hopes of feeling younger, but he died pretty soon after starting. Many believe it was due to receiving the wrong blood types. More recently Kim Jong-il used to get injections of blood from young virgins!
ReplyDeleteI wasn't able to find the published article, but here is a link to a news story about an experiment where they injected young blood into old mice and had them run a maze. The old mice injected with the young blood performed better than the old mice without the blood injections.
http://www.alternet.org/personal-health/amazing-medical-discovery-transfusions-young-blood-appear-rejuvenate-elderly
I was able to find another Nature article that is referenced in the above article: http://www.nature.com.dml.regis.edu/nature/journal/v477/n7362/abs/nature10357.html
I thought this was very interesting and it made me think not so much about blood but about grafts. Grafts are very important to restore organs that have been damaged. But a huge problem with grafts is host vs. graft disease, which can cause a multitude of problems and can lead to death. I found an article that discusses engineering grafts. It describes the different ways engraftment can be achieved, they have a good flowchart describing all the ways they are working on this but I cannot copy it into here.
ReplyDeleteHere is what they describe the flowchart as "Schematic of the basic approach used to create an engineered tissue graft for regenerative medicine applications. Briefly, a biomaterial scaffold is seeded with cells and placed into a bioreactor to stimulate differentiation, maturation, and growth of the cells into a functional construct. Ideally, a combination of contractility, electrophysiology, gene expression, and structure are used as readouts to optimize the bioreactor design and improve tissue function. The engineered tissue graft is then implanted and undergoes integration with the host tissue, which may involve vascularization and innervation depending on the tissue/organ type. Alternatively, the biomaterial scaffold may be implanted as an acellular construct and recruit endogenous cells in vivo. Example applications of the engineered tissue graft include cardiac, skeletal, ophthalmic, vascular, and neural regeneration."
A W Feinberg et al. WIREs Syst Biol Med 2011. DOI: 10.1002/wsbm.164 Copyright © 2011 John Wiley & Sons, Inc.
Would tissue engraftment on the heart or the lungs be a possible way to keep the body younger as well? I guess only time and science will tell..but it looks like we are moving in that direction.
I remember talking about this in class with you. One thing I thought about in these experiments is what exactly is creating the differences in the young and old mice? If in parabiosis, the young mice has something in it's serum that can restore the hepatic and muscle function in the old mice, then what is in the young blood that is making those old stem cells active again? While it's probably a multitude of factors such as the tissues intrinsic ability to regenerate, epigenetic changes, or even miRNA differences. In Rando's experiment, he talks about delta proteins acts as a switch in inducing stem cells to proliferate. In the old mice, factors in the young blood activates the delta proteins, while factors in the old blood turns it off. If only we can find what's in the young serum that turns the delta proteins on...
ReplyDeletehttp://www.ncbi.nlm.nih.gov/pubmed/22298767
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ReplyDeleteI think Jessica's comment is really interesting. There is a book called "Blood Work" by Holly Tucker about the history of blood transfusions and the race between the British and French to successfully transfuse a person. It is an amazing book and is very well written if you ever have free time. It goes into some of the procedures used with early transfusions as well as some of instruments used. The whole concept of blood transfusions started with dog to dog transfusion and slowly moved into animal to human transfusions. This book follows the infamous career of the French scientist Jean-Baptiste Denis. This was the guy who preformed the first blood transfusion on a human. This was in the end of the 1600's and way before anyone had a clue about blood groups or Rh factors, and the crazy part of the whole thing was that the blood donor in Denis' first human blood transfusion was a sheep. The belief was that Jesus was the lamb of God and therefore transfusing sheep blood into humans was to transfuse the blood of God into the subject. What is ever crazier is that the subject Denis was experiment on survived and even underwent two more transfusions. The reason the subject was able to withstand the foreign blood was simply because the technology for blood transfusions was terrible and very little blood was actually transfused. It was a highly entertaining book and talked a lot about the belief in the power of blood. It all comes back around at some point.
ReplyDeleteHolly, T. (2011). Blood work. New York: W.W. Norton& Company.