Getting to the heart of microRNAs

In order to understand how the heart might go wrong, it helps to understand it when it’s going right. A team of Australian researchers has done just that by cataloguing the suite of microRNAs (miRNAs) and their variants that are present in healthy heart tissue.

Understanding the miRNAs involved and how they might go wrong could lead to new treatments that can restore proper function and abundance to miRNAs.

The team, which started the project at the Victor Chang Cardiac Research Institute in 2008 and completed it at The John Curtin School of Medical Research at ANU, used next-generation SOLiD sequencing kit to map the miRNA sequences.

What they found in their survey was an unexpected amount of sequence diversity in the miRNAs in heart tissue.

“We found that many of the microRNAs in the heart take on different forms than in other tissues and that a number of the microRNAs being considered and tested as therapies were different to what was previously thought,” said study lead author Professor Thomas Preiss.

This information should help to produce new treatments for heart disease.

“MicroRNAs are already known to be deregulated in heart disease and efforts are being made to use microRNAs as a drug or drug target in treating heart disease. What we added to this is new information on the precise sequence variants of microRNAs that exist in the heart, which are not always the ones expected.

“Our cardiac microRNA compendium can now be a reference for design of microRNA-based therapeutic agents in the heart and for future research about how microRNAs are involved in heart function. “We aim to expand this work to make a similar compendium of microRNAs in diseased hearts where therapeutic intervention is more likely to be applied,” he said.

The study was published in PLoS ONE and is freely available online.