A newly discovered type of stem cell--multipotent vascular stem cells--may actually be the real factor behind vascular disease and the resulting heart attacks and strokes it typically can cause, University of California-Berkeley researchers have discovered.
The journal Nature Communications details their groundbreaking study of mouse vascular tissues, which moved forward with grants from both the National Institutes of Health and the California Institute for Regenerative Medicine. Significantly, the scientists believe this discovery potentially offers the special stem cells as a new, better target through which to treat vascular disease, rather than the smooth muscle inside the vessel wall.
"For the first time we are showing evidence that vascular diseases are actually a kind of stem cell disease," principal investigator Song Li said in a statement.
Researchers for years have, in part, blamed smooth muscle cells within blood vessel walls, plus low-density lipoproteins/bad cholesterol for damaging arteries. That combo, scientists have understood, spurs the body's immune response to produce lots of plaque whose buildup eventually blocks blood flow in the arteries. White blood cells production and fibrous scar tissue (similar to those smooth muscle tissue cells) follows, hardening the arteries and making the process even more difficult.
But challenging previously understood belief here is the discovery of multipotent vascular stem cells within the smooth muscle cells inside those blood vessel walls. The team determined that those special stem cells could differentiate into smooth muscle, nerve, cartilage, bone and fat cells, and argue that this explains why past studies have identified "de-differentiated smooth muscle cells" after vascular injury as causing vessel blockages. Further, they think that the stem cells' ability to morph into bone or cartilage might explain why arteries harden and become calcified. (Also worth noting: They found that damaging the blood vessel walls seemed to spur stem cell activity rather than mature smooth muscle cells.)
More research must be done here, though the team has determined that human carotid arteries carry the same type of multipotent vascular stem cells they found in their study. Time will tell if this new drug target leads to new and more effective vascular disease treatments.
- here's the release
- read the journal abstract