title: Effects of low frequency electromagnetic fields on the chondrogenic differentiation of human mesenchymal stem cells.
abstract: Electromagnetic fields (EMF) have been shown to exert beneficial effects on cartilage tissue. Nowadays, differentiated human mesenchymal stem cells (hMSCs) are discussed as an alternative approach for cartilage repair. Therefore, the aim of this study was to examine the impact of EMF on hMSCs during chondrogenic differentiation. HMSCs at cell passages five and six were differentiated in pellet cultures in vitro under the addition of human fibroblast growth factor 2 (FGF-2) and human transforming growth factor-β(3) (TGF-β(3) ). Cultures were exposed to homogeneous sinusoidal extremely low-frequency magnetic fields (5 mT) produced by a solenoid or were kept in a control system. After 3 weeks of culture, chondrogenesis was assessed by toluidine blue and safranin-O staining, immunohistochemistry, quantitative real-time polymerase chain reaction (PCR) for cartilage-specific proteins, and a DMMB dye-binding assay for glycosaminoglycans. Under EMF, hMSCs showed a significant increase in collagen type II expression at passage 6. Aggrecan and SOX9 expression did not change significantly after EMF exposure. Collagen type X expression decreased under electromagnetic stimulation. Pellet cultures at passage 5 that had been treated with EMF provided a higher glycosaminoglycan (GAG)/DNA content than cultures that had not been exposed to EMF. Chondrogenic differentiation of hMSCs may be improved by EMF regarding collagen type II expression and GAG content of cultures. EMF might be a way to stimulate and maintain chondrogenesis of hMSCs and, therefore, provide a new step in regenerative medicine regarding tissue engineering of cartilage.
authors: Department of Orthopaedic Surgery, Campus Großhadern, Ludwig-Maximilians-University, Munich, Germany. susanne.mayer@med.uni-muenchen.de
authors: Susanne
authors: S
authors: Mayer-Wagner
authors: Alice
authors: A
authors: Passberger
authors: Birte
authors: B
authors: Sievers
authors: Joachim
authors: J
authors: Aigner
authors: Burkhard
authors: B
authors: Summer
authors: Tobias S
authors: TS
authors: Schiergens
authors: Volkmar
authors: V
authors: Jansson
authors: Peter E
authors: PE
authors: Müller
mesh_terms: D000328:Adult; D002454:Cell Differentiation / Q000528:radiation effects*; D020219:Chondrogenesis / Q000528:radiation effects*; D004247:DNA / Q000378:metabolism; D004574:Electromagnetic Fields; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000528:radiation effects*; D016133:Polymerase Chain Reaction; D023822:Tissue Engineering
chemical_list: D006025:Glycosaminoglycans; D004247:DNA