COLOGNE, Germany — For older adults, aging bones get thinner, fracture more often, and become more susceptible to diseases like osteoporosis. Part of the reason for this is the decline in function of bone marrow stem cells, which are vital to bone integrity throughout a person’s life. Now, researchers in Germany have discovered what they’re calling a “fountain of youth” for aging stem cells. Their study finds adding acetate to these specific stem cells can reverse the aging process that weakens bones.
A team from the Max Planck Institute for Biology of Aging and the the University of Cologne say declining stem cell function is all a part of epigenetics. This is the science of changes in the genetic information that don’t alter the genes themselves, but do impact their activity. During their study, researchers suspected that changes in proteins called histones, which package and access the DNA in cells, may be the trigger behind declining stem cell function in bone marrow.
The team looked at these epigenetic changes in mesenchymal stem cells, which live in the bone marrow and form several types of cells including cartilage, bone, and fat cells.
“We wanted to know why these stem cells produce less material for the development and maintenance of bones as we age, causing more and more fat to accumulate in the bone marrow. To do this, we compared the epigenome of stem cells from young and old mice,” explains first author Andromachi Pouikli in a university release. “We could see that the epigenome changes significantly with age. Genes that are important for bone production are particularly affected.”
Acetate treatments reversing the aging process
Study authors, looking to rejuvenate the “epigenome” of stem cells, treated mouse bone marrow stem cells with a solution containing sodium acetate. The cells converted the acetate into a building block that the body’s enzymes could attach to histones. This increased their access to genes and boosted their activity in DNA.
“This treatment impressively caused the epigenome to rejuvenate, improving stem cell activity and leading to higher production of bone cells,” Pouikli reports.
The team also examined whether humans show the same kind of aging changes that mice do, using mesenchymal stem cell samples from older patients undergoing hip surgery. Cells from the elderly group also suffered from osteoporosis and showed the same epigenetic changes researchers discovered in mice.
As for using acetate as a de-aging drug, the scientists say it will take careful planning. Although acetate is actually available for consumption, the team notes rejuvenating bone health takes specific stem cell therapies to work.
“Sodium acetate is also available as a food additive, however, it is not advisable to use it in this form against osteoporosis, as our observed effect is very specific to certain cells. However, there are already first experiences with stem cell therapies for osteoporosis. Such a treatment with acetate could also work in such a case. However, we still need to investigate in more detail the effects on the whole organism in order to exclude possible risks and side effects,” explains study leader Peter Tessarz.
The study appears in the journal Nature Aging.