title: Conditions that promote primary human skeletal myoblast culture and muscle differentiation in vitro.
abstract: Conditions under which skeletal myoblasts are cultured in vitro are critical to growth and differentiation of these cells into mature skeletal myofibers. We examined several culture conditions that promoted human skeletal myoblast (HSkM) culture and examined the effect of microRNAs and mechanical stimulation on differentiation. Culture conditions for HSkM are different from those that enable rapid C2C12 myoblast differentiation. Culture on a growth factor-reduced Matrigel (GFR-MG)-coated surface in 2% equine serum-supplemented differentiation medium to promote HSkM differentiation under static conditions was compared with culture conditions used for C2C12 cell differentiation. Such conditions led to a >20-fold increase in myogenic miR-1, miR-133a, and miR-206 expression, a >2-fold increase in myogenic transcription factor Mef-2C expression, and an increase in sarcomeric α-actinin protein. Imposing ±10% cyclic stretch at 0.5 Hz for 1 h followed by 5 h of rest over 2 wk produced a >20% increase in miR-1, miR-133a, and miR-206 expression in 8% equine serum and a >35% decrease in 2% equine serum relative to static conditions. HSkM differentiation was accelerated in vitro by inhibition of proliferation-promoting miR-133a: immunofluorescence for sarcomeric α-actinin exhibited accelerated development of striations compared with the corresponding negative control, and Western blotting showed 30% more α-actinin at day 6 postdifferentiation. This study showed that 100 μg/ml GFR-MG coating and 2% equine serum-supplemented differentiation medium enhanced HSkM differentiation and myogenic miR expression and that addition of antisense miR-133a alone can accelerate primary human skeletal muscle differentiation in vitro.
authors: Department of Biomedical Engineering, Duke University, Durham, North Carolina; and.
authors: Cindy S
authors: CS
authors: Cheng
authors: Yasser
authors: Y
authors: El-Abd
authors: Khanh
authors: K
authors: Bui
authors: Young-Eun
authors: YE
authors: Hyun
authors: Rebecca Harbuck
authors: RH
authors: Hughes
authors: William E
authors: WE
authors: Kraus
authors: George A
authors: GA
authors: Truskey
mesh_terms: D000185:Actinin / Q000378:metabolism; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D002460:Cell Line; D049109:Cell Proliferation; D048429:Cell Size; D003094:Collagen / Q000378:metabolism; D003470:Culture Media / Q000378:metabolism; D004338:Drug Combinations; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007797:Laminin / Q000378:metabolism; D064326:MEF2 Transcription Factors / Q000378:metabolism; D008297:Male; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism; D024510:Muscle Development / Q000235:genetics; D032448:Myoblasts, Skeletal / Q000378:metabolism*; D061251:Primary Cell Culture; D011509:Proteoglycans / Q000378:metabolism; D013997:Time Factors; D014162:Transfection
chemical_list: D015415:Biomarkers; D003470:Culture Media; D004338:Drug Combinations; D007797:Laminin; D064326:MEF2 Transcription Factors; C578040:MEF2C protein, human; C548234:MIRN133 microRNA, human; D035683:MicroRNAs; D011509:Proteoglycans; D000185:Actinin; C059485:matrigel; D003094:Collagen
keywords: differentiation; microRNA; myogenesis; skeletal muscle; tissue engineering