Working Towards Reversing Age-Related Changes in Blood Stem Cells
Change is good.
Once upon a time (that is, back in the 50s and 60s), tired middle-aged and older persons were targeted by ads for Geritol, a "tonic" that contained lots of iron, plus 12% alcohol. The pitch was that middle-age tiredness was brought on by "iron-poor tired blood." Ultimately, the FTC went after Geritol and its makers for false advertising. As explained by Wikipedia: "Geritol was the subject of years of investigation starting in 1959 by the Federal Trade Commission (FTC). In 1965, the FTC ordered the makers of Geritol to disclose that Geritol would relieve symptoms of tiredness only in persons who suffer from iron deficiency anemia, and that the vast majority of people who experience such symptoms do not have such a deficiency. Geritol’s claims were discredited in court findings as "conduct amounted to gross negligence and bordered on recklessness," ruled as a false and misleading claim, and heavily penalized with fines totaling $812,000 ($4,251,130 as of 2013), the largest FTC fine up to that date (1973).
Fast forward to 2013. Today we actually know part of how and why blood does in fact change with age. Indeed, researchers are gaining knowledge and experiencing some success on ways to reverse the changes, as described in a press release from Lund University regarding a newly published journal article on experiments with the stem cells that generate blood. In short, the experiments are aimed at reversing epigenetic changes in which changes in blood occur as genes are switched on or off by external influences. The epigenetic changes in turn lead to a different mix of cells within blood. Now, the researchers are finding ways to undo the changes and to restore the balance of cells that was present during youth.
That’s good change. Key portions of the press release are quoted below.
"The blood of young and old people differs. In an article published recently in the scientific journal Blood, a research group at Lund University in Sweden explain how they have succeeded in rejuvenating the blood of mice by reversing, or re-programming, the stem cells that produce blood.
Stem cells form the origin of all the cells in the body and can divide an unlimited number of times. When stem cells divide, one cell remains a stem cell and the other matures into the type of cell needed by the body, for example a blood cell.*
“Our ageing process is a consequence of changes in our stem cells over time”, explained Martin Wahlestedt, a doctoral student in stem cell biology at the Faculty of Medicine at Lund University, and principal author of the article.
“Some of the changes are irreversible, for example damage to the stem cells’ DNA, and some could be gradual changes, known as epigenetic changes, that are not necessarily irreversible, even if they are maintained through multiple cell divisions. When the stem cells are re-programmed, as we have done, the epigenetic changes are cancelled.”**
The composition of blood is one example of how it ages; blood from a young person contains a certain mix of B- and T-lymphocytes and myeloid cells. “In older people, the number of B- and T-lymphocytes falls, while the number of myeloid cells increases”, said Martin Wahlestedt.
“There is a lot of focus on how stem cells could be used in different treatments, but all that they are routinely used for in clinical work today is bone marrow transplants for diseases where the blood and immune systems have to be regenerated”, said Martin Wahlestedt, continuing:
“A critical factor that gives an indication of whether the procedure is going to work or not is the age of the bone marrow donor. By reversing the development of the stem cells in the bone marrow, it may be possible to avoid negative age-related changes.”
Even if the composition of the blood in old and young mice is remarkably like that in young and elderly people, Martin Wahlestedt stressed that the science is still only at the stage of basic research, far from a functioning treatment. The research group is pleased with the results, because they indicate that it may not primarily be damage to DNA that causes blood to age, but rather the reversible epigenetic changes.
‘An epigenetic component of hematopoietic stem cell aging amenable to reprogramming into a young state’
Wahlestedt M, Norddahl GL, Sten G, Ugale A, Micha Frisk MA, Mattsson R, Deierborg T, Sigvardsson M, Bryder D.