Molecular Metabolism (Jan 2018)

Neurturin is a PGC-1α1-controlled myokine that promotes motor neuron recruitment and neuromuscular junction formation

  • Richard Mills,
  • Hermes Taylor-Weiner,
  • Jorge C. Correia,
  • Leandro Z. Agudelo,
  • Ilary Allodi,
  • Christina Kolonelou,
  • Vicente Martinez-Redondo,
  • Duarte M.S. Ferreira,
  • Susanne Nichterwitz,
  • Laura H. Comley,
  • Vanessa Lundin,
  • Eva Hedlund,
  • Jorge L. Ruas,
  • Ana I. Teixeira

Journal volume & issue
Vol. 7
pp. 12 – 22

Abstract

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Objective: We examined whether skeletal muscle overexpression of PGC-1α1 or PGC-1α4 affected myokine secretion and neuromuscular junction (NMJ) formation. Methods: A microfluidic device was used to model endocrine signaling and NMJ formation between primary mouse myoblast-derived myotubes and embryonic stem cell-derived motor neurons. Differences in hydrostatic pressure allowed for fluidic isolation of either cell type or unidirectional signaling in the fluid phase. Myotubes were transduced to overexpress PGC-1α1 or PGC-1α4, and myokine secretion was quantified using a proximity extension assay. Morphological and functional changes in NMJs were measured by fluorescent microscopy and by monitoring muscle contraction upon motor neuron stimulation. Results: Skeletal muscle transduction with PGC-1α1, but not PGC-1α4, increased NMJ formation and size. PGC-1α1 increased muscle secretion of neurturin, which was sufficient and necessary for the effects of muscle PGC-1α1 on NMJ formation. Conclusions: Our findings indicate that neurturin is a mediator of PGC-1α1-dependent retrograde signaling from muscle to motor neurons. Keywords: Skeletal muscle, PGC-1α, Neurturin, Motor neuron, Myokine