Scientists from the University of Georgia, Rob Pazdro and Yang Zhou, led a study that showed how genetics regulates aging and disease – a hormone that is essential in the aging process is apparently under genetic control.
Past studies have found that the blood levels of the hormone that is instrumental in the aging process – growth differentiation factor 11 (GDF11) – decrease over time. By restoring GDF11 in old mice, cardiovascular aging was reversed, as well as brain rejuvenation. This finding was listed as one of the top 10 breakthroughs in science in the year 2014.
The new study shows that the levels of the GDF11 are determined by genetics, offering another potential mechanism by which aging is encoded in the genome. The hope is to sustain the levels of this hormone in order to prevent various diseases.
“Finding that GDF11 levels are under genetic control is of significant interest. Since it is under genetic control, we can find the genes responsible for GDF11 levels and its changes with age,” said the study’s senior author, Rob Pazdro.
Pazdro and his colleagues confirmed the findings of the previous studies that showed that the GDF11 levels decrease over time and that the most of the depletion takes place by middle age.
The study examined the link between the GDF11 levels and markers of aging, such as lifespan in 22 genetically diverse inbred mice strains. As expected, the strains with the highest GDF11 levels lived longer than the others.
The team used gene mapping to identify seven candidate genes that may determine blood concentration levels of the GDF11 at middle age. For the first time, the study demonstrated that the GDF11 levels are strongly heritable.
“Essentially, we found a missing piece of the aging/genetics puzzle,” Pazdro said. “Very generally, we’ve made an important step toward learning about aging and why we age and what are the pathways that drive it. It’s the first step down a long road, but it’s an important step.”