It may one day be possible to fully heal a heart following a heart attack. Because heart cells lose their ability to divide soon after we are born, when the cells die – in a heart attack, say – the dead tissue is replaced by scar tissue rather than new muscle. Now Mauro Giacca of the International Centre for Genetic Engineering and Biotechnology in Trieste, Italy, and his colleagues have identified molecules that stimulate adult heart cells to divide and multiply. The work raises hopes that the cells can be coaxed into doing that later in life, giving damaged hearts a chance to fully recover.
