Abnormal short-latency synaptic plasticity in the motor cortex of subjects with Becker muscular dystrophy: a rTMS study

Stefan Golaszewski; Kerstin Schwenker; Jürgen Bergmann; Francesco Brigo; Monica Christova; Eugen Trinka; Raffaele Nardone

doi:10.1016/j.neulet.2015.11.008

Abnormal short-latency synaptic plasticity in the motor cortex of subjects with Becker muscular dystrophy: a rTMS study

Neurosci Lett. 2016 Jan 1:610:218-22. doi: 10.1016/j.neulet.2015.11.008. Epub 2015 Nov 10.

Authors

Stefan Golaszewski¹, Kerstin Schwenker², Jürgen Bergmann³, Francesco Brigo⁴, Monica Christova⁵, Eugen Trinka³, Raffaele Nardone⁶

Affiliations

¹ Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; TMS & fMRI Lab, Department of Neurology, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria. Electronic address: s.golaszewski@salk.at.
² Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; TMS & fMRI Lab, Department of Neurology, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria.
³ Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria.
⁴ Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Department of Neurological, Neuropsychological, Morphological and Movement Sciences, University of Verona, Italy.
⁵ Department of Physiology, Medical University of Graz, Graz, Austria.
⁶ Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; Department of Neurology, Franz Tappeiner Hospital, Merano, Italy.

PMID: 26562314
DOI: 10.1016/j.neulet.2015.11.008

Abstract

We used repetitive transcranial magnetic stimulation (rTMS) to further investigate motor cortex excitability in 13 patients with Becker muscular dystrophy (BMD), six of them with slight mental retardation. RTMS delivered at 5Hz frequency and suprathreshold intensity progressively increases the size of motor evoked potentials (MEPs) in healthy subjects; the rTMS-induced facilitation of MEPs was significantly reduced in the BMD patients mentally retarded or classified as borderline when compared with age-matched control subjects and the BMD patients with normal intelligence. The increase in the duration of the cortical silent period was similar in both patient groups and controls. These findings suggest an altered cortical short-term synaptic plasticity in glutamate-dependent excitatory circuits within the motor cortex in BMD patients with intellectual disabilities. RTMS studies may shed new light on the physiological mechanisms of cortical involvement in dystrophinopathies.

Keywords: Becker muscular dystrophy; Cortical plasticity; Cortical silent period; Dystrophinopathies; Glutamatergic transmission; Motor evoked potentials; Repetitive transcranial magnetic stimulation.

MeSH terms

Adolescent
Adult
Case-Control Studies
Evoked Potentials, Motor
Humans
Motor Cortex / physiopathology*
Muscular Dystrophy, Duchenne / physiopathology*
Neuronal Plasticity*
Transcranial Magnetic Stimulation*
Young Adult