Israeli and Australian researchers have taken a step toward repairing and regenerating heart tissue, in a medical breakthrough that could have wider implications for heart patients in the future.

The joint research, led by Gabriele D’Uva of Israel’s Weizmann Institute of Science in association with the Victor Chang Cardiac Research Institute in Sydney, managed to stimulate heart muscle cells to grow in mice, The Guardian reported on Tuesday.

Humans heart cells have a difficult time healing, which often complicates recoveries from heart attacks and other heart conditions — unlike salamanders or fish whose heart muscle tissue regenerates automatically.

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The medical team members behind the breakthrough are optimistic that the find is poised to have wider applications for patients who suffer from heart conditions.

“The dream is that one day we will be able to regenerate damaged heart tissue, much like a salamander can regrow a new limb if it is bitten off by a predator,” said Richard Harvey of the Victor Chang institute.

Unlike the blood, hair or skin, cells in the human heart stop dividing about a week after birth; this prevents the natural repair of damaged tissue.

“There’s always been an intense interest in the mechanism salamanders and fish use that makes them capable of heart regeneration,” Harvey explained. “There are various theories why the human heart cannot do that, one being that our more sophisticated immune system has come at a cost.”

However, researchers discovered that, by manipulating a hormone called neuregulin, used in the heart’s signaling system, they could cause heart cells to divide, leading to regeneration.

“This is such a significant finding that it will harness research activities in many labs around the world, and there will be much more attention now on how this neuregulin-response could be maximized,” Harvey said.

The method was successful in both adult and adolescent mice and the replaced tissue made the tiny hearts almost as good as new.

Harvey speculated it would take another five years before scientists know if the same process can be used in humans.

“We will now examine what else we can use, other than genes, to activate that pathway, and it could be that there are already drugs out there, used for other conditions and regarded as safe, that can trigger this response in humans,” he continued.

The research was led by D’Uva, a molecular biologist, and the findings were published on Tuesday in the scientific journal Nature Cell Biology.