Parent Project Muscular Dystrophy (PPMD) has awarded a total of $148,000 to researchers at Nationwide Children’s Hospital and the University of Missouri to help better understand and improve the treatment of cardiac disease in people with Duchenne muscular dystrophy (DMD).
The funding falls under PPMD’s Cardiac Initiative and comes from its 2018 holiday campaign, which highlighted the importance of cardiac research among DMD patients.
DMD is caused by a mutation in the DMD gene, which leads to very little or no dystrophin in muscle cells. In the heart, this results in the gradual deterioration of cardiac muscle and in cardiac disease.
“The leading cause of death among people with Duchenne is heart disease. People with Duchenne have hearts that are dystrophin deficient and undergo a progressive deterioration beginning from birth. There is also evidence that women who are carriers of Duchenne are at risk of heart disease,” Abby Bronson, senior vice president of research strategy at PPMD, said in a press release.
Over the past several years, PPMD has invested nearly $5 million in research for optimal care, management, and prevention of DMD-related cardiomyopathy (a disease of the heart muscle). The newly funded research also targets cardiac health but with a different approach.
Heart disease is often detected only at a late stage in people with DMD, largely due to little understanding about disease progression. Advancements in cardiac magnetic resonance imaging (MRI) are enabling earlier detection, which allows for early initiation of therapy and better outcomes.
Kan Hor, MD, a pediatric cardiologist at The Heart Center at Nationwide Children’s Hospital, is evaluating 1,200 cardiac MRI studies collected from more than 550 patients.
Using the $94,500 grant from PPMD, Hor and his team will continue to build a database for large-scale analysis of heart function, anatomy, and evidence of scarring among patients with DMD. It will also help researchers and industry partners identify cardiac biomarkers and develop new therapeutics.
“A major barrier to treatment is understanding the cardiac disease natural history. Surrogate cardiac MRI markers of disease are vital to not only understand and better characterize cardiac disease progression, but to assess treatment efficacy,” Hor said.
“Understanding the disease mechanism will alter the treatment paradigm from rescue to prevention and improve evidence base treatment in our journey to find the cure for Duchenne,” he added.
Despite evidence of a higher risk of cardiac disease among women who are carriers of these mutations, data on this population are still lacking.
“Deeper probing, utilizing cardiac tissue, would allow for better characterization of heart disease in carriers,” Bronson said. “Due to the difficult nature of acquiring cardiac tissue from patients, there is a lack of available tissue from carriers to better define cardiac disease progression.”
To address this gap, Duan will study carriers in a preclinical model of DMD, collecting echocardiography and cardiac MRI data, monitor heart activity, and accumulate cardiac tissue.
“To understand the molecular and cellular process in the heart of a carrier, we need to get tissue samples from the heart. Unfortunately, this is not possible in humans, but there are preclinical models that have similar clinical manifestations as Duchenne patients,” Duan said.
“Thanks to PPMD’s support, we will evaluate cardiac function in a model that is equivalent to 40 to 50 years of age in humans,” he added.
Importantly, these tissue samples will be available to the DMD research community to study the underlying processes of cardiac problems in carriers.