Heart healing tested
A new method could heal the scars left behind by heart attacks.
After a heart attack, the shock of the event leaves behind a trail of damaged heart muscle, which becomes a scar over time.
However, the scar tissue does not have the elasticity and flexibility of healthy heart muscle, meaning there can be complications with pumping and transporting blood.
For the first time, an international team of researchers has developed a method to reverse the loss of elasticity of damaged heart tissue following heart attacks.
Preclinical studies in rats found a single injection of tropoelastin into the wall of the heart in the days following a heart attack could ‘turn back the clock’ on muscle damage, making the scars ‘stretchier’ and help improve the heart’s ability to contract.
Tropoelastin is the protein building block that gives human tissue its elasticity and ability to stretch.
The results are published in Circulation Research and is the first time this potential of tropoelastin in treating heart disease has been investigated.
“This research showcases the potential of tropoelastin in heart repair and suggest further work will show exciting possibilities of its role in future treatments and therapies,” says lead researcher Dr Robert Hume who conducted the research at the Westmead Institute for Medical Research.
Four days after a heart attack, purified tropoelastin was injected into the heart.
For this injection, the researchers used a new surgical method utilising ultrasound to guide the needle into the heart wall, which is less invasive than previous methods.
After 28 days the researchers found the heart muscle, originally damaged and scarred at the beginning, regained its elasticity and resembled muscle function similar to before the heart attack.
Further tests found tropoelastin reduced scar size and essentially stabilises it by increasing its elastin content and therefore decreasing the stiffness of the scar.
Additional experiments on human cardiac fibroblasts (a subset of human heart cells responsible for maintaining the structure of a normal heart), in a petri dish showed after the cells were treated with tropoelastin, they were able to generate elastin.