Scientists describe the mechanism of heart regeneration in the zebrafish

February 12, 2018, Centro Nacional de Investigaciones Cardiovasculares
Section through a zebrafish heart after injury. Cardiomyocytes of the external heart wall are shown in blue. The regenerated tissue visible at the bottom of the image contains some green-stained cardiomyocytes, indicating their origin in the internal part of the heart (red) and their conversion to cells of the myocardial wall. Credit: CNIC

Some animals, including the zebrafish, have a high capacity to regenerate tissues, allowing them to recovery fully after cardiac injury. During this process, the heart muscle cells divide to replace the damaged tissue. However, there has been uncertainty about whether all cells contribute equally to the reconstruction of the heart wall. Now, a team of scientists led by Nadia Mercader at the Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) and the University of Bern (Switzerland), working with collaborators at the University of Zurich (Switzerland), have discovered a high level of plasticity among the cells of the zebrafish heart muscle. The study is published in Nature Communications.

After a attack, the human heart loses millions of cardiomyocytes, the cells that form the muscle wall. In contrast, other animal species have a high regenerative capacity, enabling them to replace the injured myocardium with new cardiomyocytes. One such species is the zebrafish (Danio rerio). According to first author Héctor Sánchez-Iranzo, the zebrafish "is a widely used model system in cardiovascular research into the mechanisms controlling regeneration, and an inspiration for attempts to develop future regenerative therapies."

The ability of the zebrafish heart to reestablish its function after injury depends on the capacity of its cardiomyocytes to divide and repopulate the infarcted area, thus eliminating the damaged tissue. Unfortunately, the hearts of most animals, including humans, are unable to activate this process, and therefore after an infarction the cannot regenerate the lost muscle, which is replaced by non-functional scar tissue.

Cell plasticity

Before the new study, scientists did not know if all cardiomyocytes in the zebrafish heart shared the same regenerative ability or if they were equally able to regenerate all zones of the heart muscle. Cell plasticity, the ability of to convert themselves into another cell type, is frequently observed during embryonic development, but has never before been reported during tissue regeneration in an adult organism.

In the study, the authors investigated two types of cardiomyocyte, one localized in the innermost heart regions, the trabeculae, and the other in the exterior heart wall. Scientists had presumed that during regeneration each cardiomyoctye population would give rise only to the same specialized cell type. But the CNIC study shows that cardiomyocytes from the trabeculae can contribute to the regeneration of the external heart wall. The researchers conclude that their results "reveal a high level of plasticity among cardiomyocytes and that there is more than one way to rebuild a damaged heart."

Explore further: Cardiomyocytes fuse when the heart grows and regenerates

More information: Héctor Sánchez-Iranzo et al, Tbx5a lineage tracing shows cardiomyocyte plasticity during zebrafish heart regeneration, Nature Communications (2018). DOI: 10.1038/s41467-017-02650-6

Related Stories

Cardiomyocytes fuse when the heart grows and regenerates

February 9, 2018
Cardiomyocytes fuse during cardiac development and regeneration. A scientist of the German Centre for Cardiovascular Research (DZHK) discovered these previously unknown processes with the aid of genetically modified zebrafish ...

Mouse study links heart regeneration to telomere length

May 30, 2016
Researchers at the Spanish National Center for Cardiovascular Research have discovered that the ends of heart muscle cell chromosomes rapidly erode after birth, limiting the cells' ability to proliferate and replace damaged ...

Stem Cell discovery refreshes the heart

August 7, 2017
Some people are better than others at recovering from a wounded heart, according to a new USC Stem Cell study published in Nature Genetics.

Fate of the heart: Researchers track cellular events leading to cardiac regeneration

June 19, 2013
In a study published in the June 19 online edition of the journal Nature, a scientific team led by researchers from the University of California, San Diego School of Medicine visually monitored the dynamic cellular events ...

How do you mend a broken heart?

November 22, 2016
Many lower forms of life on earth exhibit an extraordinary ability to regenerate tissue, limbs, and even organs—a skill that is lost among humans and other mammals. Now, a University of Pittsburgh researcher has used the ...

Recommended for you

Novel genetic study sheds new light on risk of heart attack

October 12, 2018
Loss of a protein that regulates mitochondrial function can greatly increase the risk of myocardial infarction (heart attack), Vanderbilt scientists reported Oct. 3 in the journal eLife.

Researchers say ritual for orthodox Jewish men may offer heart benefits

October 11, 2018
A pilot study led by researchers at the University of Cincinnati (UC) College of Medicine suggests Jewish men who practice wearing tefillin, which involves the tight wrapping of an arm with leather banding as part of daily ...

Markers of dairy fat consumption linked to lower risk of type two diabetes

October 10, 2018
Higher levels of biomarkers of dairy fat consumption are associated with a lower risk of developing type 2 diabetes, according to new research published today in PLOS Medicine. The study, in more than 60,000 adults, was undertaken ...

Seed oils are best for LDL cholesterol

October 9, 2018
If you want to lower your low-density lipoprotein cholesterol, called LDL or, colloquially, "bad cholesterol," the research is clear about one thing: You should exchange saturated fats with unsaturated fat. If you want to ...

Micropeptide restores heart function in mice

October 9, 2018
Researchers have discovered a micropeptide molecule that can restore normal heart function in mice, according to a study in eLife.

New risk test for sepsis for heart patients

October 5, 2018
Nearly one in four deaths in people with heart failure are caused by sepsis, according to new research.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.