The motor neuron response to SMN1 deficiency in spinal muscular atrophy
- 24 July 2013
- journal article
- research article
- Published by Wiley in Muscle & Nerve
- Vol. 49 (5), 636-644
- https://doi.org/10.1002/mus.23967
Abstract
Introduction: The purpose of this study was to measure and analyze motor unit number estimation (MUNE) values longitudinally in spinal muscular atrophy (SMA). Methods: Sixty‐two children with SMA types 2 and 3 were observed prospectively for up to 42 months. Longitudinal electrophysiological data were collected, including compound motor action potential (CMAP), single motor unit action potential (SMUP), and MUNE. Results: Significant motor neuron loss and compensatory collateral reinnervation were noted at baseline. Over time, there was a significant mean increase in MUNE (4.92 units/year, P = 0.009), a mean decrease in SMUP amplitude (−6.32 μV/year, P = 0.10), and stable CMAP amplitude. Conclusions: The unexpected longitudinal results differ from findings in amyotrophic lateral sclerosis studies, perhaps indicating that compensatory processes in SMA involve new motor unit development. A better understanding of the mechanisms of motor unit decline and compensation in SMA is important for assessing novel therapeutic strategies and for providing key insights into disease pathophysiology. Muscle Nerve 49: 636–644, 2014Keywords
This publication has 32 references indexed in Scilit:
- More can be lessNeurology, 2012
- Validation of the Expanded Hammersmith Functional Motor Scale in Spinal Muscular Atrophy Type II and IIIJournal of Child Neurology, 2011
- Temporal requirement for high SMN expression in SMA miceHuman Molecular Genetics, 2011
- Reliability of the modified hammersmith functional motor scale in young children with spinal muscular atrophyMuscle & Nerve, 2011
- Compound muscle action potential and motor function in children with spinal muscular atrophyMuscle & Nerve, 2010
- The PedsQL™ in pediatric patients with Spinal Muscular Atrophy: Feasibility, reliability, and validity of the Pediatric Quality of Life Inventory™ Generic Core Scales and Neuromuscular ModuleNeuromuscular Disorders, 2009
- Sonic Hedgehog Is a Polarized Signal for Motor Neuron Regeneration in Adult ZebrafishJournal of Neuroscience, 2009
- Zebrafish survival motor neuron mutants exhibit presynaptic neuromuscular junction defectsHuman Molecular Genetics, 2009
- Embryonic motor axon development in the severe SMA mouseHuman Molecular Genetics, 2008
- Knockdown of the survival motor neuron (Smn) protein in zebrafish causes defects in motor axon outgrowth and pathfindingThe Journal of cell biology, 2003