title: Impact of static magnetic fields on human myoblast cell cultures.
abstract: Treatment of skeletal muscle loss due to trauma or tumor ablation therapy still lacks a suitable clinical approach. Creation of functional muscle tissue in vitro using the differentiation potential of human satellite cells (myoblasts) is a promising new research field called tissue engineering. Strong differentiation stimuli, which can induce formation of myofibers after cell expansion, have to be identified and evaluated in order to create sufficient amounts of neo-tissue. The objective of this study was to determine the influence of static magnetic fields (SMF) on human satellite cell cultures as one of the preferred stem cell sources in skeletal muscle tissue engineering. Experiments were performed using human satellite cells with and without SMF stimulation after incubation with a culture medium containing low [differentiation medium (DM)] or high [growth medium (GM)] concentrations of growth factors. Proliferation analysis using the alamarBlue assay revealed no significant influence of SMF on cell division. Real-time RT-PCR of the following marker genes was investigated: myogenic factor 5 (MYF5), myogenic differentiation antigen 1 (MYOD1), myogenin (MYOG), skeletal muscle α1 actin (ACTA1), and embryonic (MYH3), perinatal (MYH8) and adult (MYH1) skeletal muscle myosin heavy chain. We detected an influence on marker gene expression by SMF in terms of a down-regulation of the marker genes in cell cultures treated with SMF and DM, but not in cell cultures treated with SMF and GM. Immunocytochemical investigations using antibodies directed against the differentiation markers confirmed the gene expression results and showed an enhancement of maturation after stimulation with GM and SMF. Additional calculation of the fusion index also revealed an increase in myotube formation in cell cultures treated with SMF and GM. Our findings show that the effect of SMF on the process of differentiation depends on the growth factor concentration in the culture medium in human satellite cultures. SMF alone enhances the maturation of human satellite cells treated with GM, but not satellite cells that were additionally stimulated with serum cessation. Therefore, further investigations are necessary before consideration of SMF for skeletal muscle tissue engineering approaches.
authors.affiliation: Department of Otolar-yngology, Head and Neck Surgery, Medical Faculty Mannheim, University Hospital Mannheim, D-68135 Mannheim, Germany. jens.stern-straeter@umm.de
authors.forename: Jens
authors.initials: J
authors.lastname: Stern-Straeter
authors.forename: Gabriel Alejandro
authors.initials: GA
authors.lastname: Bonaterra
authors.forename: Stefan S
authors.initials: SS
authors.lastname: Kassner
authors.forename: Anne
authors.initials: A
authors.lastname: Faber
authors.forename: Alexander
authors.initials: A
authors.lastname: Sauter
authors.forename: Johannes D
authors.initials: JD
authors.lastname: Schulz
authors.forename: Karl
authors.initials: K
authors.lastname: Hörmann
authors.forename: Ralf
authors.initials: R
authors.lastname: Kinscherf
authors.forename: Ulrich Reinhart
authors.initials: UR
authors.lastname: Goessler
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D002454:Cell Differentiation; D002455:Cell Division; D049109:Cell Proliferation; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D060526:Magnetic Fields; D008280:Magnetics / Q000379:methods*; D018482:Muscle, Skeletal / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D017570:MyoD Protein / Q000235:genetics / Q000378:metabolism; D051787:Myogenic Regulatory Factor 5 / Q000235:genetics / Q000378:metabolism; D018008:Myogenin / Q000235:genetics / Q000378:metabolism; D061251:Primary Cell Culture; D060888:Real-Time Polymerase Chain Reaction; D032496:Satellite Cells, Skeletal Muscle / Q000166:cytology / Q000378:metabolism*; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D015415:Biomarkers; C497417:MYF5 protein, human; D017570:MyoD Protein; C057363:MyoD1 myogenic differentiation protein; D051787:Myogenic Regulatory Factor 5; D018008:Myogenin