It also explains hardening of the arteries, says Linda L. Demer, MD, PhD. Demer led the UCLA team that discovered what the cells can do.
"The reason that arteries harden is that bone is growing in them," Demer says in a news release.
Demer's team previously showed that this bone doesn't come from someplace else in the body. They traced the bone growth to calcifying vascular cells or CVCs, found in the artery walls and heart valves. Unlike normal cells, CVCs can turn into other kinds of cells.
"We have now shown clearly that CVCs not only become bone but cartilage, marrow, and smooth muscle as well," Demer says. The new findings appear in the Oct. 28 early access issue Circulation: Journal of the American Heart Association.
And they have one extra trick: They can self renew, thus representing a lifelong source of new bone and cartilage cells.
On the other hand, CVCs can't turn into fat cells. But that may be a big advantage if the cells can be harvested, grown to larger numbers, and used to treat disease.
"Older women who are losing bone in their skeletons are still forming fresh new bone in their [heart artery]," Demer says. "That suggests they still have the capacity to create bone. It may be possible to harness that process to create a therapy for bone loss."