A well-known aquarium fish with a remarkable ability to regenerate damaged cardiac muscle may hold clues in repairing a broken heart, scientists said.
The piscatorial marvel is the zebrafish (Danio rerio), a small, stripey denizen of tropical rivers and aquaria which is also a prized lab tool for investigating tissue growth, according to a study to be published on Thursday.
One of the first animals to have its DNA code sequenced, the zebrafish can rebuild its heart when as much as a fifth of it has been cut away, previous research has found.
A key to this remarkable bounce-back ability could lie with a gene called gata4, which normally is triggered in the zebrafish embryo to form hearts, according to the paper, published by the British science journal Nature.
Scientists at Duke University Medical Center used a gene that exudes a glowing fluorescent gene as a telltale of when gata4 is activated.
In uninjured zebrafish, there was no fluorescence.
But when they clipped a small section of the heart, a sub-population of cardiac muscle cells along the outer wall of the ventricles began to fluoresce and eventually multiply, filling the wound.
Figuring how these cells are mustered could help victims of heart attacks, which kills cardiac cells and leaves tissue dangerously scarred.
"By studying this important cell population, we expect results that could help in the repair of diseased human hearts," said lead author Kazu Kikuchi, quoted in a press release issued by the university.
"We don't know the instructions or the mechanisms yet that mobilise these cells or cause them to proliferate, but we now know that they are the cells that are participating in new muscle growth," said Kenneth Poss, a Duke professor of cell biology,
"Our human hearts don't seem so complex that they shouldn't have the capacity to regenerate."