Hendrikje Van Andel-Schipper was the oldest person in the world when she died in 2005. New research on the 115-year-old woman’s body has found that the secret to a long life may be found in stem cells.
It is thought that Andel-Schipper is the oldest person ever to donate their body to science, and it was a jackpot for longevity researchers who want to better understand aging. Dutch researchers have been using her body in their investigations to try to find out why some people live longer. The research is led by Dr. Henne Holstege, at Amsterdam’s VU University Medical Center. His latest study, published in the journal Genome Research, looked for mutations in the genes of Andel-Schipper’s blood, using whole-genome sequencing of white blood cells.
Researchers studying healthy blood cells from the woman found over 400 mutations. The mutations were found in the parts of the genome not associated with disease, and her body apparently accepted them. She was in remarkably good health until her death, and had no signs of disease or dementia. Holstege says she was extremely old and cognitively healthy.
Human blood is replenished by hematopoietic stem cells found in bone marrow. Everyone starts with about 20,000 of these cells, 1,300 of which are “active.” These divide to create different kinds of blood cells. When researchers examined the 115-year-old woman’s white blood cells that had mutations, they found that at the time of her death her peripheral blood supply was apparently coming from only two active stem cells, according to Holstege.
There are many gene mutation studies due to links to diseases like cancer, but not much is known about gene mutations in healthy people. Mistakes in the replication of DNA often happen during cell division, but usually these mutations are removed by the body because they can lead to disease. The mutations found in Andel-Schipper’s blood were not associated with disease.
Researchers also found that the telomeres on Andel-Schipper’s white blood cells were very short. Telomeres are at the ends of the chromosomes and protect them from damage, but they get a little shorter each time cells divide.
There may be a limit to how many times stem cells can divide, and possibly they eventually die from division exhaustion. Researchers think it may be possible that the 115-year-old woman died from stem cell exhaustion, which could also be cause of death for many people who live to extreme old age. Researchers say more studies are needed to find out if this is true.
The study’s implications for aging are notable. If stem cells have a limit to their lifespan, then there is also a limit to human life. Now the question is, “what if stem cells could be replaced when they stop functioning?” Holstege said the results of the research on the 115-year-old woman’s body hint that the secret to longer life may be replenishing the stem cells. If these cells are taken from the body when an individual is young, and given back when they are older, perhaps life could be extended.
By Beth A. Balen