Scientists reported that an international research team in London has identified a tiny piece of the genetic material, ribonucleic acid (RNA), linked to heart failure and by applying an experimental compound that blocked the material to prevent heart attacks in mice.

The compound antagomir came from Regulus Therapeutics (a joint venture between U. S. biotech companies Alnylam Pharmaceuticals Inc. and Isis Pharmaceuticals Inc.). This was used to block tiny strands of ribonucleic acid called microRNA, which regulate the making of genes into proteins. The researchers found that a failing heart was likely to have three- to five-times more of a particular microRNA called miR-21. Mice that were given the experimental compound antagomir that blocked miR-21 were seen to have the heart failure silenced or blocked while the mice who did not receive the treatment developed the condition.

Kleanthis Xanthopoulos, Regulus Chief Executive said, "We view this new study as a landmark event in the advancement of microRNA therapeutics as a new class of innovative medicines. We believe that this is the first study to clearly demonstrate therapeutic efficacy for targeting microRNAs in an animal model of human disease."
Stefan Engelhardt, who led the research at the University of Wuerzburg in Germany, along with Thomas Thum said the mice with the failure who were subsequently given the compound improved. "We could both prevent cardiac disease and cure some aspects of cardiac disease," said Engelhardt "Heart function and tissue damage improved in both cases."

Glaxo tied up with Regulus Therapeutics to develop and market new microRNA-targeted treatments for conditions caused by chronic inflammation, such as rheumatoid arthritis and inflammatory bowel disease in April.

The study was published in the journal Nature.