Affordable Access

Exposure of mouse preosteoblasts to pulsed electromagnetic fields reduces the amount of mature, type I collagen in the extracellular matrix.

  • Sakai, Yoshitada1
  • Patterson, Thomas E
  • Ibiwoye, Michael O
  • Midura, Ronald J
  • Zborowski, Maciej
  • Grabiner, Mark D
  • Wolfman, Alan
  • 1 Department of Biomedical Engineering, Lerner Research Institute of The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195, USA.
Published Article
Journal of orthopaedic research : official publication of the Orthopaedic Research Society
Publication Date
February 2006
PMID: 16435357


We tested the hypothesis that exposure of a mouse preosteoblast cell line to pulsed electromagnetic fields (PEMF) would affect components of the extracellular matrix. We report that exposure of MC3T3-E1 cells to a single PEMF waveform significantly reduced the amount of mature, alpha1(I) collagen in the extracellular matrix (ECM) and the conditioned medium, without affecting the amount of total ECM protein. This decrease was not due to changes in the steady-state level of Col1A1 mRNA or to degradation of mature collagen. We then tested the effect of three distinct PEMF waveforms, two orthogonal coil orientations, and two waveform amplitude levels on the amount of alpha1(I) collagen in the conditioned medium. A sequence of factorial ANOVAs and stepwise regression modeling revealed that the period (duration) of the individual pulses accounted for a significant proportion of the variance associated with the amount of alpha1(I) collagen in the conditioned medium. The total variance accounted for, however, was small (R(2)=0.155, p<0.001 and R(2)=0.172, p<0.001, in the horizontal and vertical orientations, respectively). The positive and negative regression coefficients for the coil orientations revealed that the influence of pulse period was significantly different for the orthogonal coil orientations (p<0.001). The findings imply that the dominant influence of PEMF on the amount of mature, alpha1(I) collagen in the ECM is related to variables other than those expressed in the time-amplitude domain. The results provide objective direction toward identifying waveform characteristics that contribute to the observed between-waveform differences with regard to collagen. Advances in this area may lead toward improving waveforms and waveform delivery protocols.

Report this publication


Seen <100 times