Zebrafish Can Help Repair Cardiovascular Impairment, Damaged Heart

Developmental biologist and study author Jan Philipp Junker from the Berlin Institute for Medical Systems Biology in Germany recently said they wanted to find out how zebrafish can revive heart tissue following an injury.

A ScienceAlert report specified that there are remarkable creatures. Not only are they see-through, but they can also grow new organs. It is already known these tiny translucent fish could regenerate retinal tissue in their eyes.

Essentially, the study chronicles the cascade of occurrences resulting in heart regeneration in zebrafish.

In humans, cardiac muscle cells known as cardiomyocytes cannot restore or revive like the zebrafish heart cells are doing.

Zebrafish for Heart Health

Published in the Nature Genetics journal, the study was led by Junker and Panáková, a cell signaling researcher from Max Delbrück Center for Molecular Medicine.

The human cardiomyocytes, starved of oxygen during a heart attack, become impaired, and permanent scarring, also known as fibrosis, forms in place of lost muscle, leaving the heart weaker than before.

Nonetheless, zebrafish can regrow up to 20 percent of their one-millimeter-sized hearts within a few months of a heart injury.

This new study reveals that connective tissue cells, also known as fibroblasts, are the conductors of the heart regeneration process in this particular fish species, producing proteins and acting as repair signals.

Dealing with Heart AIlments

Excitingly, the new study results are coming hot on the coattails of other promising regenerative medicine initiatives that either repair or replace damaged hearts with cell-based treatments or drugs that emulate molecules that exist in zebrafish.

In early 2022, surgeons implanted a pig heart into a human patient for the first time, although unfortunately, the man died two months later.

A couple of months ago, researchers also pinpointed the human cells that help the human heart patch itself up following a heart attack.

More so, in June, researchers successfully treated a heart attack in mice using an mRNA technique that delivers genetic instructions to heart muscle cells to repair themselves.

New Cardiomyocytes Formed

In this new research, the study authors zapped the young hearts of animals with an extremely cold needle to emulate a human heart attack, also known as myocardial infarction, and what happened.

Astonishingly, the instantaneous response to the injury is quite similar, Junker explained. However, while the process in humans stops at that point, it's carrying on in the fish. They are forming new cardiomyocytes capable of contracting.

Applying single-cell sequencing approaches, the team scanned roughly 200,000 heart cells separated from zebrafish before and after injury, extracting genomic information from individual cells to find out which ones were active in an impaired heart.

The researchers found three fibroblasts temporarily entered an activated state, switching on genes that encode muscle-constructing proteins like collagen XII, promoting connective tissue growth, a related Discover Magazine report said.

Related information about Zebrafish used in medicine is shown on Victo Chang Cardiac Research Institute's YouTube video below:

Check out more news and information on Fish and Heart Health in Science Times.