We cut a finger and the skin heals. But what if hearts could heal too?

Researchers in Israel recently found a molecule in newborns that might help, some day. The team at the Weizmann Institute of Science have identified a molecule found in newborns that appears to control the renewal process, assisting regeneration in damaged hearts, according to a study published in Nature early this month.

The team is looking at how the molecule, Agrin, could treat MI victims. Agrin seems to unlock the renewal process, enabling the repair of heart muscle. In MI, cardiomyocytes are replaced with scar tissue that does not contract or pump. But the team, led by Eldad Tzahor, an associate professor, is working on a treatment that would naturally regenerate damaged tissue.

With a single injection into a mouse that had suffered a heart attack, damaged muscle began to heal completely in about a month, allowing full function. Over time, living heart tissue replaced scar tissue. Like human fetuses, mice hearts can regenerate and repair—until the mouse is about a week old. The team speculates that Agrin also affects the body's inflammatory and immune responses to a heart attack and the pathways that suppress scarring.

"Clearly this molecule sets a chain of events in motion," Tzahor said in a statement. "We discovered that it attaches to a previously unstudied receptor on the heart muscle cells, and this binding takes the cells back to a slightly less mature state—closer to that of the embryo—and releases signals that may, among other things, initiate cell division."

Pre-clinical studies in larger animals are underway in Germany.

Baby steps, for sure—but stay tuned.