Heart function also needs to be mointored in patients with spinal muscular atrophy (SMA).
These are the findings from a study conducted by Nationwide Children's Hospital and published online ahead of print in
Human Molecular Genetics. This is the first study to report cardiac dysfunction in mouse models of SMA.
SMA is a debilitating neurological disease that leads to wasting away of muscles throughout the body. Historically, scientists and physicians believed that SMA only affected skeletal muscles; however, new data suggests that this genetic disease may also impact the heart.
"A few studies regarding SMA patients have implicated the involvement of the cardiovascular and the autonomic nervous system," said the study's co-author Brian Kaspar, PhD, principal investigator in the Center for Gene Therapy at The Research Institute at Nationwide Children's Hospital. "However, there have been few to no highly powered and controlled studies to determine how common these cardiovascular anomalies are in these patients."
The reports of altered blood flow and slowed heart rate in some SMA patients prompted Kaspar's team to examine whether a cardiac deficit is present in a mouse model of severe SMA, developed by Arthur Burghes, PhD, professor of Molecular and Cellular Biochemistry at The Ohio State University College of Medicine, which is routinely used for drug and therapeutic-based screening.
They analyzed heart structure of the SMA mice compared with normal mice, and found that there were significant structural changes occurring in the heart of the SMA mice, along with severely impaired left-ventricular function. SMA mice also had significantly lower heart rates. After examining the underlying structure of the mouse heart cells they found it similar to the cellular structure of a heart biopsy from patient with type 3 SMA.