( When a portion of a zebrafish's heart i...)Key to zebrafish heart regeneration uncovered

The scientists further discovered that key growth factors facilitate the interaction between the cell mass and the protective covering, encouraging the formation of new heart muscle.

Many cell biologists believe the ability to regenerate damaged heart tissue may be present in all vertebrate species, but that for unknown reasons, mammals have "turned off" this ability over the course of evolution. Zebrafish could provide a model to help researchers find the key to unlocking this dormant regenerative capacity in mammals, and such an advance could lead to potential treatments for human hearts damaged by disease, the Duke scientists said.

"If you look in nature, there are many examples of different types of organisms, such as axolotls, newts and zebrafish, that have an elevated ability to regenerate lost or damaged tissue," said Kenneth Poss, Ph.D., senior researcher for the team, which published the findings on Nov. 3, 2006, in the journal Cell. First authors of the paper were Alexandra Lepilina, M.D., and Ashley Coon.

"Interestingly, some species have the ability to regenerate appendages, while even fairly closely related species do not," Poss added. "This leads us to believe that during the course of evolution, regeneration is something that has been lost by some species, rather than an ability that has been gained by other species. The key is to find a way to 'turn on' this regenerative ability."

The research was supported by the National Institutes of Health, the American Heart Association, the March of Dimes and the Whitehead Foundation.

Scientists previously had suspected that zebrafish regenerated their heart tissue by the di
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Source:Duke University Medical Center