Can microRNAs be used to help diagnose and treat coronary heart disease?

MicroRNAs in ischaemic heart disease and diabetes mellitus: from cardiac surgery to basic science (and back?)

Coronary heart disease is the UK’s biggest killer. It is caused by a blockage in the coronary arteries, the large blood vessels supplying nutrients and oxygen to heart muscle. The problem is aggravated by diabetes, which damages the small blood vessels of the heart. Cardiac surgeons can treat people with coronary heart disease by performing a coronary artery-bypass-graft, which allows blood to bypass the blocked parts of the coronary arteries. But the procedure can cause complications, including kidney damage, especially in people with diabetes and it is not suitable for people with disease in small blood vessels. We need to identify new biomarkers – molecular ‘flags’ in the blood - that could help doctors predict which patients are more likely to experience complications of the procedure and find new therapies that can reverse small vessel disease. MicroRNAs are tiny molecules that can circulate in our blood and can regulate the proteins produced by our cells. BHF Professor Costanza Emanueli, newly appointed BHF Chair of Cardiovascular Science at the University of Bristol, is an expert in microRNAs. In mice, she has discovered microRNAs linked with diabetes and coronary heart disease. The BHF has now awarded a grant to Professor Emanueli to carry out laboratory-based microRNA research to identify targets for new drugs and new biomarkers that could help people with coronary heart disease, with or without diabetes. They will find out if specific microRNA changes have an impact on heart disease associated with diabetes, and if these changes can be reversed using drugs that block or mimic microRNAs. The group will also look at microRNA and small blood vessel disease, whether altering microRNA levels boosts new blood vessel growth in tissues that have died off from lack of blood. Professor Emanueli will study human heart cells, heart tissue biopsies, blood samples and mouse models of coronary heart disease and diabetes, to work out how microRNAs are affected in disease and how they move from within heart cells into the circulation in response to disease or surgery. The mouse studies will identify promising microRNA targets to take forward and translate into people in the clinic in future work. MicroRNAs circulating in the blood may also become new biomarkers that can be used to benefit patients having heart surgery by identifying those who may be at increased risk of complications.