The blind fish that could be the key to repair broken hearts

Medical researchers are studying a species of fish capable of repairing their own hearts. They hope to use their discoveries to repair the damage to the heart in humans.

The fish in question is the Mexican tetra (Astyanax Mexicanus), which can be found along the western edge of the Caribbean Sea. Their genetics gives them the incredible ability to regenerate their heart after an injury, although it 's an evolutionary quirk that gave researchers clues about how to "get it right. exploit this genetic gift.

The quirk appeared about 1.5 million years ago, when grouse on the surface of the water were periodically washed away by floodwaters in caves. Over time, the floodwaters became blurred and some species became trapped in these caves, where they had to adapt or die. Due to the evolution of cavernicolous fish, they have lost the ability to regenerate. At the same time, they lost their color and their sight; these traits have become biologically superfluous in caverns deprived of light.

The researchers compared the cave tetra with their counterparts at the surface that repair the heart and identified three "genomic loci" – specific traits of the genome – that they linked to the regeneration of the heart.

The search was published in Cell reports, having been financed by the British Heart Foundation.

Two genes in particular, lrrc10 and caveolin, were found to be more active in the surface tetra. In the case of lrrc10, it had been shown to play a role in heart performance in mice and humans.

Researchers believe that the ability of surface fish to prevent scarring is a key element in understanding heart regeneration. after a heart injury, such as a heart attack, the human heart (and that of the cave tetra) creates a scar tissue that replaces the dead cells. This scar tissue subsequently prevents a heart from accomplishing its main task: to pump blood into the body. In contrast, in the surface tetra, cardiac cells are reconstructed without scar tissue.

According to the report, it is hoped that new research on tetra's genetic makeup may one day help humans, millions of whom suffer from heart and circulatory diseases in the UK alone:

"An extrapolation from Astyanax Mexicanus could provide an indication of why adult mammals have lost the ability to regenerate their hearts during evolution and could ultimately lead to strategies to promote a optimal repair of the human heart. "