Fish Genes Hold Key To Repairing Damaged Hearts

Recent research funded by the British Heart Foundation and published in Cell Reports suggests that the Mexican tetra fish’s remarkable ability to repair its heart after damage is done by using a gene called Irrc10.

Dr. Mathilda Mommersteeg, Associate Professor of Developmental and Regenerative Medicine at the University of Oxford and her team studied the genetic codes of the tetra river fish , (which has the heart healing DNA code) in comparison to the tetra cave fish (which does not) to discover what special mechanisms are required for heart repair. They found tetra river fish have three areas of genomes that are prominent in its ability to repair their hearts.

They discovered two genes, Irrc10 and caveolin that could be key in the river fish’s ability to repair their hearts.

Researchers also studied the gene Irrc10 in the zebrafish which also has the ability to repair its own heart after injury. When they de-activated this gene, they found that the zebrafish could no longer repair their hearts.

Why this interest by the British Heart Foundation? There are hundreds of thousands of people in the UK who have had heart attacks leaving them debilitated and life expectancy is worse than for many cancers.

During a heart attack, the heart muscle is deprived of oxygen, heart muscle cells die then are replaced by scar tissue which keeps the heart muscle from properly contracting, reducing the heart’s capability to pump blood throughout the body.

Because people can’t regenerate their damaged hearts after a heart attack, often the only solution is a heart transplant. Researchers are hoping they will be able to unlock the secrets of the tetra and the zebrafish in order to one day provide the human heart the ability to heal itself.

Professor Metin Avkiran, Associate Medical Director at the British Heart Foundation, said: “These remarkable findings show how much there is still to learn from the rich tapestry of the natural world. It’s particularly interesting that the ability of the river fish to regenerate its heart may arise from an ability to suppress scar formation. We now need to determine if we can exploit similar mechanisms to repair damaged human hearts.”

Mommersteeg, said: “A real challenge until now was comparing heart damage and repair in fish with what we see in humans. But by looking at river fish and cave fish side by side, we’ve been able to pick apart the genes responsible for heart regeneration.

“Heart failure is a cruel and debilitating illness that more than half a million people across the UK are living with. It’s in its early days but we’re incredibly excited about these remarkable fish and the potential to change the lives of people with damaged hearts.”