Stem cells can spawn other types of body cells, but they have another striking capability—they remain young. Researchers have now harnessed this ability to boost the life spans of mice and refurbish some of their tissues. Although the approach won’t work in humans, it could lead to ways to keep our bodies vigorous even as we get older.
“It’s a beautiful piece of work,” says genome scientist Howard Chang of Stanford University School of Medicine in Palo Alto, California, who wasn’t connected to the research. The study, he adds, reinforces the idea that “aging is not just a passive process. We can intervene to change the outcome.”
Like our hair and skin, our chromosomes show our age. Chromosomes carry molecular attachments, known as epigenetic marks, that help control how tightly DNA coils and how active genes are. As we get older, the arrays of these marks change, potentially fouling up the precisely coordinated patterns of gene activity that keep our cells working.
Epigenetic modifications aren’t permanent, however. By turning on a few genes normally active only in embryos, researchers can “reprogram” adult body cells into stem cells. This process returns epigenetic marks to their youthful settings and seems to rejuvenate even elderly cells. In one 2011 study, scientists reprogrammed cells from people as old as 101 in the lab, resetting their epigenetic marks and tuning up their metabolism. But could this chromosomal reboot provide similar benefits outside the lab dish?To read more, click here.