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PubMed · 12372817

Mechanical stimulation improves tissue-engineered human skeletal muscle.

Courtney A Powell·Beth L Smiley·John Mills·Herman H Vandenburgh
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Abstract

Human bioartificial muscles (HBAMs) are tissue engineered by suspending muscle cells in collagen/MATRIGEL, casting in a silicone mold containing end attachment sites, and allowing the cells to differentiate for 8 to 16 days. The resulting HBAMs are representative of skeletal muscle in that they contain parallel arrays of postmitotic myofibers; however, they differ in many other morphological characteristics. To engineer improved HBAMs, i.e., more in vivo-like, we developed Mechanical Cell Stimulator (MCS) hardware to apply in vivo-like forces directly to the engineered tissue. A sensitive force transducer attached to the HBAM measured real-time, internally generated, as well as externally applied, forces. The muscle cells generated increasing internal forces during formation which were inhibitable with a cytoskeleton depolymerizer. Repetitive stretch/relaxation for 8 days increased the HBAM elasticity two- to threefold, mean myofiber diameter 12%, and myofiber area percent 40%. This system allows engineering of improved skeletal muscle analogs as well as a nondestructive method to determine passive force and viscoelastic properties of the resulting tissue.

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Biocompatible MaterialsCollagenCytoskeletonDrug CombinationsElasticityHumansHypertrophyLamininMuscle ContractionMuscle Fibers, SkeletalMuscle, SkeletalPhysiologyProteoglycansStress, MechanicalTissue EngineeringNASA Discipline MusculoskeletalNon-NASA CenterJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Courtney A Powell, Beth L Smiley, John Mills, Herman H Vandenburgh. 2002. Mechanical stimulation improves tissue-engineered human skeletal muscle.. https://doi.org/10.1152/ajpcell.00595.2001

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