London, Mar 25 (ANI): Duke University Medical Center scientists have uncovered cells that mend a broken heart.
We, humans, have very limited ability to regenerate heart muscle cells. But damaged heart muscles in the highly regenerative zebrafish have given Duke scientists a few ideas that may lead to new directions in clinical research and better therapy after heart attacks.
"Our hearts don't seem so complex that they shouldn't have the capacity to regenerate," said Kenneth Poss, Ph.D., senior author of the study in Nature and professor of cell biology at Duke. The data in this study showed that the major contributors to the regeneration of surgically removed heart muscle came from a subpopulation of heart muscle cells (cardiomyocytes) near the area where the removal occurred.
The study appears in the March 25 issue of Nature.
The team labeled cells in the heart and found that cells that activated the gata4 gene upon injury ultimately contributed to regenerating the heart muscle.
The team first used a labeled "fluorescent reporter" fish that shows the presence of gata4, a gene required for heart formation in the developing embryo. They found that fluorescence was undetectable in uninjured zebrafish ventricles, but when they clipped a small section of the heart, a subpopulation of cardiac muscle cells along the outer wall of the ventricles began to fluoresce. Some of these cells near the removal site ultimately proliferate and integrate into the wound, replacing the injury clot.
"We don't know the instructions or the mechanisms yet that mobilize these cells or cause them to proliferate, but we now know that they are the cells that are participating in new muscle growth," said Poss, who is also an investigator in the Howard Hughes Medical Institute.
Finding a key origin of heart muscle provides a target for studies that will help scientists understand cardiac muscle regeneration, said lead author Kazu Kikuchi, a postdoctoral ellow in the Poss lab. "By studying this important cell population, we expect results that could help in the repair of diseased human hearts." (ANI)