Related Experiment Video
Updated: May 17, 2026
Assessing Functional Performance in the Mdx Mouse Model
Published on: March 27, 2014
The mdx mouse as a model for carnitine deficiency in the pathogenesis of Duchenne muscular dystrophy
Zarazuela Zolkipli1, Lydia Mai, Anne-Marie Lamhonwah
1Division of Neurology, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
Introduction:
Muscle and cardiac metabolism are dependent on the oxidation of fats and glucose for adenosine triphosphate production, for which L-carnitine is an essential cofactor.
Methods:
We measured muscle carnitine concentrations in skeletal muscles, diaphragm, and ventricles of C57BL/10ScSn-DMDmdx/J mice (n = 10) and compared them with wild-type C57BL/6J (n = 3), C57BL/10 (n = 10), and C3H (n = 12) mice. Citrate synthase (CS) activity was measured in quadriceps/gluteals and ventricles of mdx and wild-type mice.
Results:
We found significantly lower tissue carnitine in quadriceps/gluteus (P < 0.05) and ventricle (P < 0.05), but not diaphragm of mdx mice, when compared with controls. CS activity was increased in mdx quadriceps/gluteus (P < 0.03) and ventricle (P < 0.02). This suggests compensatory mitochondrial biogenesis.
Conclusions:
Decreased tissue carnitine has implications for reduced fatty acid and glucose oxidation in mdx quadriceps/gluteus and ventricle. The mdx mouse may be a useful model for studying the role of muscle carnitine deficiency in DMD bioenergetic insufficiency and providing a targeted and timed rationale for L-carnitine therapy.
