title: Extremely low frequency magnetic fields inhibit adipogenesis of human mesenchymal stem cells.
abstract: It was reported that obese (Ob/Ob) mice lose their weight and fat when treated with 0.5 T direct current electromagnetic fields. We also observed that 7.5 Hz, 0.4 T rotation of extremely low frequency magnetic fields (ELF-MF) has an inhibitory effect on obesity. Mesenchymal stem cells (MSCs) are multi-potent cells capable of differentiating to different MSC lineages, including adipose. We hypothesized that inhibitory effects of ELF-MF on obesity may be related to the differentiation of MSCs to adipocytes. In the present study, we investigated the effects of 7.5 Hz, 0.4 T ELF-MF on differentiation of human umbilical cord MSCs. We found that ELF-MF inhibited adipogenic differentiation (exposed 2 h/day for 15 days) of MSCs but had no effect on osteogenic differentiation (exposed 2 h/day for 21 days). Moreover, ELF-MF inhibited adipocyte-specific expression of peroxisome proliferator-activated receptor 2 (PPARγ2). ELF-MF promoted c-Jun N-terminal kinase (JNK)-dependent intracellular signaling in MSCs. Furthermore, activation of the non-canonical Wnt pathway provoked the inhibition of PPARγ2 expression resulting in suppression of adipogenic differentiation. In addition, the effects of ELF-MF on growth and apoptosis of MSCs were not observed. Our data indicated that ELF-MF of 7.5 Hz, 0.4 T inhibited the adipogenic differentiation of MSCs via JNK-dependent Wnt signaling pathway, but had no effect on the growth and function of MSCs, suggesting the inhibitory effect of ELF-MF on obesity may be attributed to the inhibition of differentiation of MSCs into adipocytes. This study may provide a potential approach for the treatment of obesity.
authors.affiliation: The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, P.R. China.
authors.forename: Leilei
authors.initials: L
authors.lastname: Du
authors.forename: Hongye
authors.initials: H
authors.lastname: Fan
authors.forename: Huishuang
authors.initials: H
authors.lastname: Miao
authors.forename: Guangfeng
authors.initials: G
authors.lastname: Zhao
authors.forename: Yayi
authors.initials: Y
authors.lastname: Hou
mesh_terms: D050156:Adipogenesis / Q000502:physiology / Q000528:radiation effects*; D017209:Apoptosis / Q000528:radiation effects; D015153:Blotting, Western; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D060526:Magnetic Fields / Q000009:adverse effects*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology / Q000528:radiation effects*; D010012:Osteogenesis / Q000502:physiology / Q000528:radiation effects*; D047495:PPAR gamma / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014470:Umbilical Cord / Q000166:cytology / Q000502:physiology / Q000528:radiation effects; D060449:Wnt Signaling Pathway / Q000502:physiology / Q000528:radiation effects
chemical_list: D047495:PPAR gamma; D048031:JNK Mitogen-Activated Protein Kinases
keywords: ELF-MF; MSCs; PPARγ2; adipogenic differentiation; obesity