Electrical stimulation of biofidelic engineered muscle enhances myotube size, force, fatigue resistance, and induces a fast-to-slow-phenotype shift

Physiol Rep. 2024 Oct;12(19):e70051. doi: 10.14814/phy2.70051.

Abstract

Therapeutic development for skeletal muscle diseases is challenged by a lack of ex vivo models that recapitulate human muscle physiology. Here, we engineered 3D human skeletal muscle tissue in the Biowire II platform that could be maintained and electrically stimulated long-term. Increasing differentiation time enhanced myotube formation, modulated myogenic gene expression, and increased twitch and tetanic forces. When we mimicked exercise training by applying chronic electrical stimulation, the "exercised" skeletal muscle tissues showed increased myotube size and a contractility profile, fatigue resistance, and gene expression changes comparable to in vivo models of exercise training. Additionally, tissues also responded with expected physiological changes to known pharmacological treatment. To our knowledge, this is the first evidence of a human engineered 3D skeletal muscle tissue that recapitulates in vivo models of exercise. By recapitulating key features of human skeletal muscle, we demonstrated that the Biowire II platform may be used by the pharmaceutical industry as a model for identifying and optimizing therapeutic drug candidates that modulate skeletal muscle function.

Keywords: dexamethasone; electrical stimulation; engineered skeletal muscle; skeletal muscle contractility.

MeSH terms

  • Cell Differentiation
  • Cells, Cultured
  • Electric Stimulation* / methods
  • Humans
  • Muscle Contraction
  • Muscle Fatigue*
  • Muscle Fibers, Fast-Twitch / physiology
  • Muscle Fibers, Skeletal / physiology
  • Muscle Fibers, Slow-Twitch / physiology
  • Muscle, Skeletal / physiology
  • Phenotype
  • Tissue Engineering / methods