Tensile Forces and Nanofiber Alignment Influence Both Innervated and Non-Innervated Skeletal Myofiber Formation in...

Area of Science:

• Biomedical Engineering
• Developmental Biology
• Tissue Engineering

Background:

• Muscle tissue generates force, but its dynamic response to external forces during development is less understood.
• Previous work established engineered muscle with innervation promoting myofiber formation and neuromuscular junctions.

Purpose of the Study:

• To investigate the effects of mechanical forces and scaffold topology on innervated and non-innervated engineered muscle.
• To explore how exogenous forces influence myocyte development in a controlled environment.

Main Methods:

• Fabrication of engineered muscle using skeletal myocytes, spinal motor neurons, and aligned poly-caprolactone nanofiber scaffolds.
• Application of tensile elongation using custom mechanobioreactors to the engineered muscle platform.
• Analysis of myocyte characteristics (thickness, width, fusion) under varying conditions of innervation, mechanical loading, and scaffold alignment.

Main Results:

• Nanofiber scaffold alignment significantly influenced myocyte thickness, width, and fusion in both innervated and non-innervated conditions.
• Combined tensile loading and nanofiber alignment led to increased myocyte fusion.
• The multi-faceted approach mimicked in vivo developmental microenvironments.

Conclusions:

• Scaffold topology and biomechanical loading synergistically enhance myofiber formation and maturation.
• This engineered muscle platform provides a valuable model for studying muscle development and response to mechanical stimuli.
• Findings offer principles for fabricating engineered muscle for therapeutic applications, such as repairing major muscle defects.