From VOA Learning English, this is the Health Report.
Could young blood be the answer to cheating death? It may sound like the story in a vampire movie but now there is scientific research that supports the theory. U.S. scientists have discovered a protein in the blood in young mice that can undo some effects of aging in old mice. The same protein is present in human blood. Two papers published in the journal "Science" discuss this protein, called GDF11.
Researchers at Harvard University said GDF11 improved the brain and muscle ability of older mice. This protein is found in high levels in the blood of young mice. In one experiment, the scientists increased the levels of GDF11 in aging mice by surgically connecting the blood flow systems of young mice to the old mice. Blood containing higher levels of GDF11 flowed among both groups.
In another experiment, they injected the protein into old mice. The old mice formed new blood vessels. The animals' blood flow improved. And the aging process changed directions, or reversed, in every tissue the researchers observed. The scientists saw the greatest change in the old mice that shared blood flow with the young.
Researcher Lee Rubin is a professor of stem cell research at Harvard's Stem Cell Institute. His team looked at the effect of GDF11 on brain tissue. He says the operation produced structural changes in the old brain making it more like the young brain. Another scientist said that GDF11 repaired DNA damage linked to aging. There is growing hope that GDF11 might someday repair and renew unhealthy human hearts.