title: A short-term extremely low frequency electromagnetic field exposure increases circulating leukocyte numbers and affects HPA-axis signaling in mice.
abstract: There is still uncertainty whether extremely low frequency electromagnetic fields (ELF-EMF) can induce health effects like immunomodulation. Despite evidence obtained in vitro, an unambiguous association has not yet been established in vivo. Here, mice were exposed to ELF-EMF for 1, 4, and 24 h/day in a short-term (1 week) and long-term (15 weeks) set-up to investigate whole body effects on the level of stress regulation and immune response. ELF-EMF signal contained multiple frequencies (20-5000 Hz) and a magnetic flux density of 10 μT. After exposure, blood was analyzed for leukocyte numbers (short-term and long-term) and adrenocorticotropic hormone concentration (short-term only). Furthermore, in the short-term experiment, stress-related parameters, corticotropin-releasing hormone, proopiomelanocortin (POMC) and CYP11A1 gene-expression, respectively, were determined in the hypothalamic paraventricular nucleus, pituitary, and adrenal glands. In the short-term but not long-term experiment, leukocyte counts were significantly higher in the 24 h-exposed group compared with controls, mainly represented by increased neutrophils and CD4 ± lymphocytes. POMC expression and plasma adrenocorticotropic hormone were significantly lower compared with unexposed control mice. In conclusion, short-term ELF-EMF exposure may affect hypothalamic-pituitary-adrenal axis activation in mice. Changes in stress hormone release may explain changes in circulating leukocyte numbers and composition. Bioelectromagnetics. 37:433-443, 2016. © 2016 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Stan
authors.initials: S
authors.lastname: de Kleijn
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Gerben
authors.initials: G
authors.lastname: Ferwerda
authors.affiliation: Faculty of Health and Environmental Sciences, Central University of Technology, Free State, Bloemfontein, South Africa.
authors.forename: Michelle
authors.initials: M
authors.lastname: Wiese
authors.affiliation: Cell Biology and Immunology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands.
authors.forename: Jos
authors.initials: J
authors.lastname: Trentelman
authors.affiliation: Immunent B.V. and Neiding B.V., Veldhoven, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Cuppen
authors.affiliation: Faculty of Science, Department of Cellular Animal Physiology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
authors.forename: Tamas
authors.initials: T
authors.lastname: Kozicz
authors.affiliation: Faculty of Health and Environmental Sciences, Central University of Technology, Free State, Bloemfontein, South Africa.
authors.forename: Linda
authors.initials: L
authors.lastname: de Jager
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Peter W M
authors.initials: PW
authors.lastname: Hermans
authors.affiliation: Cell Biology and Immunology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands. lidy.vankemenade@wur.nl.
authors.forename: B M Lidy
authors.initials: BM
authors.lastname: Verburg-van Kemenade
mesh_terms: D000818:Animals; D004574:Electromagnetic Fields / Q000009:adverse effects*; D007030:Hypothalamo-Hypophyseal System / Q000166:cytology* / Q000528:radiation effects*; D007958:Leukocyte Count; D051379:Mice; D010913:Pituitary-Adrenal System / Q000166:cytology* / Q000528:radiation effects*; D015398:Signal Transduction / Q000528:radiation effects*; D013997:Time Factors
keywords: ELF-EMF; immune response; in vivo exposure; leukocytes; stress