An Italian breakthrough could open the door to new therapies to combat a deadly condition that can cause cardiac arrest and different forms of heart disease.
The discovery, made by a team led by Cesare Peschle of the Italian Higher Health Institute (ISS), concerns cardiac hypertrophy - the thickening of the heart muscle.
Although a degree of heart enlargement can be healthy if it is a result of physical exercise, cardiac hypertrophy is generally linked to life-threatening pathological problems.
"Cardiac hypertrophy occurs when the heart cells get bigger in order to pump more blood in response to stress caused, for example, by hypertension," explained Peschle.
"At first the effect is positive, but in the long term cardiac hypertrophy leads to a series of complications, including arrhythmia, which can cause sudden death, and heart failure".
Peschle's team have discovered that a natural molecule produced by the human body - miR-133 - has a critical role in determining cardiac hypertrophy.
"We saw that the hearts of mice with hypertrophy had a low level of miR-133," he said.
"By increasing the amount of miR-133 in their hearts we managed to prevent hypertrophy caused by high blood pressure".
This is important, he said, because it could lead to the development of heart therapies based on this natural molecule, rather than on synthetic medicines.
"Up to now heart therapies have been based on drugs, but now we have a therapy which uses a molecule that is present in the organ and therefore is free from toxic effects," Peschle said.
"Our results have opened up a new, very important phase for the treatment of heart disease".
The head of the ISS, Enrico Garaci, claimed the team's discovery was "revolutionary".
Peschle said the next stage will be to test the use of miR-133 to prevent cardiac hypertrophy in humans.
Peschle coordinated the research with Gianluigi Condorelli of the Milan-based IRCCS institute.
Scientists from the University of California - San Diego also took part in the study, which has been published in the latest edition of US journal Nature Medicine.
