title: Mechanical stimulation improves tissue-engineered human skeletal muscle.
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.
authors.affiliation: Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Courtney A
authors.initials: CA
authors.lastname: Powell
authors.forename: Beth L
authors.initials: BL
authors.lastname: Smiley
authors.forename: John
authors.initials: J
authors.lastname: Mills
authors.forename: Herman H
authors.initials: HH
authors.lastname: Vandenburgh
mesh_terms: D001672:Biocompatible Materials; D003094:Collagen; D003599:Cytoskeleton / Q000502:physiology; D004338:Drug Combinations; D004548:Elasticity; D006801:Humans; D006984:Hypertrophy; D007797:Laminin; D009119:Muscle Contraction / Q000502:physiology*; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000502:physiology*; D018482:Muscle, Skeletal / Q000166:cytology* / Q000502:physiology; D010827:Physiology / Q000295:instrumentation* / Q000379:methods; D011509:Proteoglycans; D013314:Stress, Mechanical; D023822:Tissue Engineering
chemical_list: D001672:Biocompatible Materials; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen