Source: Centro Nacional de Investigaciones Cardiovasculares
Summary: A team of researchers has discovered a high level of plasticity among the cells of the zebrafish heart muscle.
After a heart attack, the human heart loses millions of cardiomyocytes, the cells that form the muscle wall. But some animals, including the zebrafish, have a high capacity to regenerate tissues, allowing them to recover fully after cardiac injury which enables them to replace the injured myocardium with new cardiomyocytes. However, there has been uncertainty about whether all cells contribute equally to the reconstruction of the heart wall. 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 findings were published in the journal Nature Communications.
Before this 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. In the study, the authors investigated 2 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 cardiomyocyte 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 (the ability of cells to convert themselves into another cell type) among zebrafish cardiomyocytes and that there is more than one way to rebuild a damaged heart.
First author Héctor Sánchez-Iranzo said, “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.”
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