MDF Magazine Issue 61 April 2020 (2)

MD
Exercising to
Improve Function in
Muscular Dystrophy
By Anna Williams
News Center, Feinberg School of Medicine
Northwestern University
10 June 2019
moderate. The mice were exercised on a treadmill
three times a week, for six months.
The investigators found that both exercise regimens
were benefi cial in mice and did not increase muscle
damage or fi brosis. In particular, the mice showed an
improvement in skeletal muscle function, reduction in
cardiac decline and increase in respiratory capacity.
Low- and moderate-intensity exercise improved
muscle, heart and breathing function in an animal
model of Duchenne muscular dystrophy, according to a
Northwestern Medicine study.
The study, published in Scientifi c Reports, was led by
Elizabeth McNally, MD, PhD, the Elizabeth J. Ward
Professor of Genetic Medicine and director of the
Center for Genetic Medicine.
Duchenne Muscular Dystrophy (DMD) is the most
common and severe form of muscular dystrophy, a
group of genetic diseases that cause progressive
weakness and loss of muscle. There is currently no
cure for DMD, which occurs in children, and almost
exclusively in boys. Symptoms of the disease began
early in childhood, and by the age of 13, most patients
require the use of a wheelchair.
The goal of treatment for DMD is to control symptoms
and improve quality of life. The impact of exercise in the
disease, however, has not been well understood.
“It has long been a question whether exercise is bad
for patients with Duchenne Muscular Dystrophy,” said
McNally, also a professor of Medicine in the Division
of Cardiology and of Biochemistry and Molecular
Genetics. “It has been suggested by some that exercise
worsens the disease. However, we know that not
exercising is bad for the heart and cardiovascular
system.”
In the current study, McNally and her collaborators
investigated the impact of aerobic exercise using an
animal model of DMD. The scientists examined mice
with the same genetic disorder as patients with DMD
and tested two different levels of exercise, low and
“For most measurements, the moderate intensity was
generally a little better, but for many measurements
even low-intensity exercise was benefi cial,” McNally
explained. “With exercise, the mice became more
active, even when they were not on the treadmill. The
exposure to exercise made them move more.”
Furthermore, the scientists found that exercise was
associated with a dose-dependent increase in
serum levels of adiponectin, indicating that the hormone
could serve as a biomarker for favorable response to
exercise in DMD.
Although the study’s fi ndings suggest that low-intensity
or moderate-intensity exercise may be benefi cial in
DMD, the authors note that further research in humans
is needed to determine appropriate levels of exercise
and the impact on muscle, cardiac and respiratory
function.
Aaron Zelikovich, ’16 BA, was the fi rst author of the
paper. Nancy Kuntz, MD, professor of Pediatrics in
the Division of Neurology and Epilepsy and in the Ken
and Ruth Davee Department of Neurology; Mattia
Quattrocelli, PhD, a postdoctoral fellow in
McNally’s laboratory; and Isabella Salamone,
a student in Feinberg’s Driskill Graduate Program in
Life Sciences (DGP), were also co-authors.
The study was supported by National Institutes of Health
grants AR052646, HL061322 and T32 DK007169, the
Muscular Dystrophy Association, and Parent Project
Muscular Dystrophy.
Article available at: https://news.feinberg.northwestern.
edu/2019/06/exercising-to-improve-function-in-muscular-dystrophy/
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