Stem cell aging is a complex topic with many interacting processes and is widely accepted as an important factor in aging. Age-related loss of stem cell function is accompanied by epigenetic changes and alterations to how metabolism functions.
Researchers believe that if we can understand the mechanisms underlying these changes, we can likely develop novel therapies that target them to prevent age-related decline and disease.
Reviewing stem cell aging
A team of researchers, including Juan Carlos Izpisua Belmonte, who famously reversed epigenetic aging in living animals late last year, have created a comprehensive review of what is currently known about stem cell aging.
We know that epigenetic changes are an important reason why we age, as Belmonte demonstrated last year when he and his team reversed age-related epigenetic changes in mice, and they lived longer and were more youthful as a result. They used a technique similar to how iPSC stem cells are created outside the body, but this was done in living animals. We discussed the paper in detail during the May edition of Journal Club, a monthly science show supported by our Lifespan Heroes.
Recent studies have shown that metabolism plays a key role in regulating epigenetic changes in cells, and this dramatically affects the aging process. This is why studies like the recent one showing how caloric restriction slows the rate of epigenetic changes are important in this context, and they confirm the role metabolism plays here.
The new review investigates current knowledge about the various mechanisms of stem cell aging and the links between epigenetic changes and metabolism. As well as discussing the complex interplay between these forces, the review also explores how these interactions sense and respond to environmental stress in order to maintain function, a process known as homeostasis, which simply means balance, and how environmental stimuli influence and regulate stem cell function.
Finally, the review looks at recent advances in the development of therapies that can reverse stem cell aging by rescuing metabolism from the downward, age-related spiral.
The take-home point here is that while the researchers highlight the complex nature of stem cell aging and the interaction between metabolism and epigenetic changes, and they acknowledge that there is more research to be done before we fully understand how these changes begin in the first place, they remain optimistic.
The researchers here make no bones about their intentions to slow down aging and to treat age-related diseases using novel therapies, which they hope to develop. They also specifically talk about removing senescent stem cells as part of that strategy in order to increase both healthspan and lifespan. The researchers here finish on the idea of conquering age-related decline and dysfunction in aged tissues to reverse age-related changes.
This may not seem like a big deal, but senior academic researchers are involved, such as Juan Carlos Izpisua Belmonte, who has recently shown his dedication to aging research. He dares to push boundaries and has been instrumental in breakthrough studies in recent months; to have someone so influential pushing to do something about aging is very important indeed.
 Ren, R., Ocampo, A., Liu, G. H., & Belmonte, J. C. I. (2017). Regulation of Stem Cell Aging by Metabolism and Epigenetics. Cell Metabolism, 26(3), 460-474.
 Ocampo, A., Reddy, P., Martinez-Redondo, P., Platero-Luengo, A., Hatanaka, F., Hishida, T., … & Araoka, T. (2016). In vivo amelioration of age-associated hallmarks by partial reprogramming. Cell, 167(7), 1719-1733.
 Maegawa, S., Lu, Y., Tahara, T., Lee, J. T., Madzo, J., Liang, S., … & Issa, J. P. J. (2017). Caloric restriction delays age-related methylation drift. Nature Communications, 8.