December 6, 2012 | Corrinne

Heart muscle cells aren’t very good at replacing themselves. If hearts become damaged – after a heart attack, for example – then scar tissue forms, and the heart can’t pump blood as well as it used to.

But now we may be able to help the heart along using ‘microRNAs’ – small molecules that are similar to DNA. MicroRNAs bind to DNA and control what proteins it makes. Scientists have used them to regenerate damaged heart tissue in living mice, whose heart capacity returned to nearly normal. Could this mean new hope for human patients?