Fish heart science may hold key to preventing heart failure

University of Guelph researchers think humans can benefit from new knowledge on how how fish can change the size of their heart with temperature changes.
Todd Gillis said there are similarities between the trout heart and the human heart. (Fish World )

University of Guelph researchers have identified a protein that could be key in preventing eventual heart failure after a heart attack.

The protein is TGF-Beta1, which regulates collagen production in fish.

In colder temperatures, the fish heart grows in size and gets stronger so it can continue to pump blood despite its higher viscosity. The fish does this by adding collagen to its heart.

This project is the work of PhD candidate, Elizabeth Johnston, who worked under the supervision of Todd Gillis. The study is titled "Transforming growth factor beta-1 (TGF-β1) stimulates collagen synthesis in cultured rainbow trout cardiac fibroblasts," and was recently published in the Journal of Experimental Biology.

Gillis said by understanding how fish add and remove collagen from their hearts, researchers may be able to find a way to regulate the formation and removal of scar tissue on human hearts after a heart attack.

The scar tissue that forms after a heart injury replaces important muscle and makes the heart stiffer — which eventually leads to heart failure.

"If you're able to either regulate or control the amount of scar tissue that forms — and after the heart is able to repair itself, to remove that scar tissue — you would perhaps slow down or prevent that downward spiral in the heart that leads to heart failure," he said.

Currently Gillis' lab is trying to understand the genes and the proteins that are involved in activating the removal of collagen. He said it will take a number of years before it's tested clinically.