New research into how calcium affects hearts in people with cardiomyopathy

16th May 2016

The largest biomedical research agency in the world is to fund a study into how calcium affects how the heart beats in cardiomyopathy.

Calcium helps trigger heart muscle contraction.  Too much can cause stronger heartbeats and too little weaker beats.

So the National Institutes of Health in America has awarded 1.8 million dollars to a project to study how the heart’s calcium is regulated and how to correct a calcium imbalance via cardiac cells.

Researcher Jose Pinto, from the Florida State University College of Medicine, will spend the next five years on the project which was previously funded by the American Heart Association.

Dr Pinto, an assistant professor in the department of biomedical sciences, said the long -term goal was to identify components inside the cardiac cell that are involved in the development of hypertrophic and dilated cardiomyopathy and open the door for more effective treatment strategies inside the cell.

Troponin C is a gene that Pinto calls "the calcium sensor of the heart," the on-off switch controlling contractions in the heart. His team is working to demonstrate that mutations in that gene cause the heart to pump blood in one of two harmful ways.

One results in hypertrophic cardiomyopathy, where the heart becomes abnormally thick and initially pumps more forcefully. The other is dilated cardiomyopathy, where the pumping chamber stretches and the walls become thinner -- and pump more weakly, he said.

"In the hypertrophic heart, it can be compared to a dimmer switch; you turn it only a little bit and the lights come on -- it's hypersensitive to calcium," Dr Pinto said. "In dilated cardiomyopathy, it's like you switch, switch, switch, switch, and the lights never come on."

He hopes to demonstrate Troponin C's role and focus on a possible treatment for hypertrophic cardiomyopathy using an enzyme found inside heart cells.

"The beautiful thing about the enzyme we are targeting is that it has been shown to be only present in the heart," Dr Pinto said. "The main problem with most drugs developed to target enzymes is that they affect other cells, healthy cells, and the patient experiences unwanted side effects."

He believes that targeting hypertrophic cardiomyopathy in the heart cells may help prevent those unwanted side effects.

"If your heart is working above the normal range all the time, that is going to lead to problems," he said. "The unique thing about our project is that we're going to be studying what the deletion of this enzyme will do in the heart after the disease has already started. We are looking at the reversal of the disease: Can we do something to bring the heart back to normal?"