Scientists Find New Heart Cell That Boosts Vessel Growth

Imagine if your heart could rebuild its own damaged tissue after a heart attack, growing new blood vessels exactly where they're needed. Scientists just moved one step closer to making that possible.

Researchers at Weill Cornell Medicine have discovered a previously unknown cell type that acts like a construction crew for the heart's blood vessel network. The team, led by Dr. Jingli Cao, found these special "perivascular" cells while studying zebrafish, animals known for their remarkable ability to regenerate heart tissue.

The new cells do something surprisingly smart. They wrap around developing blood vessels and release a chemical signal that tells the vessels when to stop growing. Think of it like having a supervisor on a construction site who knows exactly when the building is complete.

Dr. Cao's team discovered that when the heart is injured and oxygen levels drop, a gene called scxa switches on. This activates cells in the epicardium, the thin outer layer of the heart, transforming them into these vessel-supporting cells. They then surround coronary blood vessels and produce a special type of collagen that keeps vessel growth in check.

"During development or when the heart is damaged, you need to build the right amount of blood vessel and you need to know when to stop," Dr. Cao explained. His lab found this system provides exactly that control.

The findings matter because human hearts can't regenerate the way zebrafish hearts can. After a heart attack, our hearts form scar tissue instead of new, functioning muscle. But humans have a related gene called SCX that might work similarly.

Why This Inspires

Dr. Cao's team is already working with human heart cells and cardiac organoids to explore whether they can activate the same regenerative programs. The goal? Creating what he calls a "biological bandage" that could be placed on damaged areas of the heart, triggering controlled growth of muscle and blood vessels right where they're needed.

The research doesn't promise a single miracle cure. Dr. Cao is clear that heart regeneration will likely require multiple factors working together. But each discovery adds another piece to the puzzle.

Graduate student Björn Perder and postdoctoral fellow Dr. Yu Xia worked alongside Dr. Cao to catalog which genes activate when the zebrafish heart is injured. Their painstaking work revealed how the epicardium, once thought to be just a protective coating, actually serves as a reservoir of cells ready to rebuild damaged tissue.

The study received support from the New York State Stem Cell Science program, the National Institutes of Health, and the American Heart Association. These organizations recognized that understanding how simple animals regenerate could unlock secrets to human healing.

One day, doctors might be able to switch on dormant regenerative programs in human hearts, steering our own cells to repair damage from the inside out.