Blood, the elixir of life, could actually be the miracle needed to reverse aging. Scientist have shown that this is the case in mice when blood from young mice was shown to rejuvenate the muscles and brain of older mice. According to the New York Times on May 4, the scientists believe this latest discovery can lead to successful treatment for Alzheimer’s and heart disease.
This young blood fixing old bodies is a theory that has been around for a long time. Back in the 1950s an experiment that fused an old and young rat together so they would share both blood supplies came with amazing results.
Cornell University was the setting over a half of a century ago for Clive McCay’s experiments on rats. McCay and his colleagues stitched together the skin on the rats’ flanks, pairing them with one old and one young rat. The blood from the old flowed into the young and vice versa, according to the Washington Post.
When McCay and his team performed a necropsy on each of the rats when the experiment was done, they found that the old rats were showing signs of rejuvenation in younger mice. They found muscles that didn’t age as much as they had expected they would. Amazing as this was, this experiment was done during an era where science knew so little about the body and the process of rejuvenating itself.
This stitching of the two rats together is called parabiosis and in 2005, McCay’s experiments were revisited with mice. A group of scientists headed by Dr. Rando, a professor of neurology at Stamford University, found that the muscles of the old mice now healed at the rate of the muscles of the young mice.
The young mice got the worst end of this deal. They prematurely aged and their muscles healed more slowly and their stem cells did not turn into new cells as quickly as they did before they had the old blood on board.
Amy J. Wagers, who was a member of Dr. Rando’s team, moved to Harvard but continued the blood-mice experiments. Last year Wager and her team demonstrated that they could rejuvenate the hearts of old mice with blood from young mice.
The breakthrough came when Wagner’s team isolated a protein called GDF 11. This was found in abundance in the blood of young mice, but they discovered it was scarce in the blood of old mice. To see if GDF 11 was the protein that was the crucial factor of this rejuvenation, they produced a supply of the protein and injected it into the old mice. GDF 11 rejuvenated their hearts, all on its own.
These studies went on to see brains of old mice could be rejuvenated with the blood from young mice. In 2011 Dr. Saul Villeda, who was a graduate student back then, reported that old mice receiving young blood had a burst of new neurons in the hippocampus. This is the region of the brain that plays a big part in forming memories.
Dr. Villeda continued with his studies with the young blood on old mice and was “stunned by the results.” Using the stitching method, parbiosis, the blood supply coming from the younger mice gave the older mice a growth of blood vessels in the brain.
Dr Wagner injected the GDF 11 into mice and found the same type of results, but the change was not as large as the results that Dr. Villeda got with using blood. While this has a ways to go, the risks for this rejuvenation also need to be studied.
A professor of bioengineering, Irina M. Conboy, suggests that this may dramatically increase the incidence of cancer, which is one of the risks that will need assessment through tests. Scientist are also concerned about waking up stem-cells and the possibility that they end up multiplying uncontrollably.
Although this may sound as simple as a transfusion of younger blood to fix those ailments coming on as you age, it is not that simple. This is far away from being tested on people. Right now it is in its early stages on mice, but it does sound extremely promising.
Some scientists are warning about being careful and “not overselling this.” New blood for rejuvenation needs all types of testing, but despite the possible risks talked about, scientist see “a bright future for parabiosis.