Effect of acute transcranial magnetic stimulation on intracellular signalling in human skeletal muscle

Authors

  • Ferdinand von Walden
  • Eva-Karin Gidlund
  • Chang Liu
  • Nerrolyn Ramstrand
  • Jessica Norrbom
  • Nils von Wachenfelt
  • Henrik Kjellgren
  • Carl Johan Sundberg
  • Eva Pontén
  • Björn Alkner

DOI:

https://doi.org/10.2340/16501977-2643

Keywords:

electromyography, skeletal muscle, transcranial magnetic stimulation

Abstract

Objective: To investigate the potential of an acute bout of transcranial magnetic stimulation to induce anabolic signalling. Design: Experimental intervention on healthy subjects. Subjects: Ten healthy subjects, 5 women and 5 men (mean age 32 years; standard deviation (SD) 4). Methods: Transcranial magnetic stimulation, resulting in contraction of the quadriceps muscles, was applied at a frequency of 10 Hz for 10 s followed by 20 s of rest, repeated 40 times over 20 min. Electromyography and force data were collected for all transcranial magnetic stimulation sequences. Muscle biopsies were obtained from the vastus lateralis muscle before and 1 and 3 h after stimulation for evaluation of the molecular response of the muscle. Results: The described stimulation decreased phosphorylation of AKT at Thr308 (1 h: ?29%, 3 h: ?38%; p?<?0.05) and mTOR phosphorylation at Ser2448 (1 h: ?10%; ns, 3 h: ?21%; p?<?0.05), both in the anabolic pathway. Phosphorylation of AMPK, ACC and ULK1 were not affected. c-MYC gene expression was unchanged following transcranial magnetic stimulation, but rDNA transcription decreased (1 h: ?28%, 3 h: ?19%; p?<?0.05). PGC1?-ex1b mRNA increased (1 h: 2.3-fold, 3 h: 2.6-fold; p?<?0.05), which also correlated with vastus lateralis electromyography activity, while other PGC-1? variants were unchanged. Conclusion: Acute transcranial magnetic stimulation of skeletal muscle in weight-bearing healthy individuals did not induce anabolic signalling, but some signs of impaired muscle anabolism were detected. Therefore, these results do not support the use of acute transcranial magnetic stimulation in preventing muscle wasting.

Downloads

Download data is not yet available.

Downloads

Published

2020-02-27

How to Cite

von Walden, F., Gidlund, E.-K., Liu, C., Ramstrand, N., Norrbom, J., von Wachenfelt, N., … Alkner, B. (2020). Effect of acute transcranial magnetic stimulation on intracellular signalling in human skeletal muscle. Journal of Rehabilitation Medicine, 52(2), 1–10. https://doi.org/10.2340/16501977-2643

Issue

Section

Original Report