'New way' to repair heart damage

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Scientists say they have found a new way to mend damage to the heart. When cells turn into fully-formed adult heart muscle they stop dividing, and cannot replace tissue damaged by disease or deformity, reports BBC.
But a US team have found a way to coax the cells to start dividing again, raising hopes they could be used to regenerate healthy tissue.The study, carried out on mice and rats by Children's Hospital Boston, appears in the journal Cell.
If the same mechanisms identified by the researchers can be shown to work in the human heart, it opens up real possibilities for new and more efficient ways to treat people with heart disease.The researchers say their work could provide an alternative to stem cell therapy, which is still largely untested, and carries a potential risk of side effects. In theory, it could be used to treat heart attack patients, those with heart failure and children with congenital heart defects. The key ingredient is a growth factor known as neuregulin1 (NRG1).
The Boston team envisages patients going to a clinic for daily infusions of NRG1 over a period of weeks. However, researcher Dr Bernhard Kühn said more work to establish the safety of the therapy was needed before it could be tested in humans. It has long been thought that the heart was incapable of repairing itself.
Heart muscle cells (cardiomyocytes) proliferate during prenatal development, but were thought to lose that ability shortly after birth. However, recent research has indicated that the adult cells do have some ability to replace themselves at a low level.
The latest study provides firm evidence that this is true - and that NRG1 can ramp up the process significantly. The Boston team tested the ability of various molecules to spur cell division in cultured cardiomyocytes, including several factors known to drive proliferation of the cells during prenatal development.