In 2005, 115-year-old Hendrikje van Andel-Schipper passed away to old age healthy and disease-free. At the time of her death, Schipper became the oldest person to have her body donated to science. Longevity researchers were interested in understanding why a healthy person suddenly dies of old age. A group of Dutch researchers may be onto something. After researching the woman’s stem cells, Dutch researchers, led by Henne Holstege, may have found out why this woman lived disease-free for well over a century and why her body shut down when it did.
Long life may be limited by stem cell’s ability to divide
In their research at the VU University Medical Center in Amsterdam, Hostege and her team went to work sequencing Schipper’s genome, looking for specific gene mutations as they searched for a possible secret to long life. The study, published in the journalGenome Research, reported that cell division cannot last forever and a person’s lifespan may be limited by the stem cell’s ability to divide efficiently.
During normal stem cell division, four different types of blood cells result. When the division is abnormal, gene mutations can occur. The researchers also found an absence of dangerous mutations in Schipper’s blood, suggesting that her body’s cellular processes were superior and were able to repair or efficiently replace damaged cells. Cells with dangerous mutations might have been cleansed more readily, keeping cancer from taking hold. In fact, all mutations within her blood were found to be harmless and were only the result of mistaken replications of DNA during her life. Thus, the “mother” blood stem cells multiplied effectively, providing clones that replenished her blood.
Only two stem cells remaining in 115-year-old woman
When they studied Schipper’s stem cells, everything became even clearer. She only had two active stem cells remaining. A normal human body starts out with about 20,000 stem cells, with about 1,300 being active. In Schipper’s body, only two stem cells remained active. The researchers believe that this discovery could help explain how active stem cell count relates to a person’s life span. Since Schipper had only two active stem cells remaining, her biological clock had reached its last hour.
The researchers also observed the length of telomeres present in her blood cells. Telomeres are the protective caps on chromosomes that “wear down” over time. As a person ages, telomeres shorten. Schipper’s telomeres were extremely short, denoting her old age.
The researchers concluded that the secret to long life could be rooted in a person’s stem cells and telomere lengths. The amount of stem cells remaining may indicate an expiration date. The researchers showed that, in Schipper’s later years, white blood cells were derived from her last set of stem cells.
When the stem cells expire, they can no longer divide into other cells. They exhaust and lose their division capabilities. Finding a way to enhance the division process and preserve it through efficient cellular functions may be the key to extending one’s life.
Researcher discusses methods to lengthen life on Earth
This stem cell secret to longevity may eventually prove that properly utilized nutrition can make cellular division processes more efficient, preserving telomere lengths, allowing a person to live longer.
One solution to living a longer life was brought up by Hostege. She thought up the idea of injecting aging bodies with youthful stem cells as a way to extend life on Earth. “If I took a sample now and gave it back to myself when I’m older, I would have long telomeres again — although it might only be possible with blood, not other tissues,” she said.
She asked, “Is there a limit to the number of stem cell divisions, and does that imply that there’s a limit to human life? Or can you get round that by replenishment with cells saved from earlier in your life?”
Hostege stated that more research needs to be conducted: “We need to analyze the genomes of more individuals just as special as Mrs. van Andel-Schipper: cognitively healthy and extremely old.”
What researchers should be looking for next are ways to preserve stem cells through nutrient and antioxidant use.
Sources for this article include: