Pulsed electromagnetic field (PEMF) treatment reduces expression of genes associated with disc degeneration in human intervertebral disc cells.

Author: Miller SL1, Coughlin DG2, Waldorff EI3, Ryaby JT4, Lotz JC5.
Affiliation: 1Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: millers@orthosirg.ucsf.edu. 2Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: coughlind@orthosurg.ucsf.edu. 3Orthofix, Inc., 3451 Plano Parkway, Lewisville, TX, 75056, USA. Electronic address: erikwaldorff@orthofix.com. 4Orthofix, Inc., 3451 Plano Parkway, Lewisville, TX, 75056, USA. Electronic address: jamesryaby@orthofix.com. 5Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: lotzj@orthosurg.ucsf.edu.1Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: millers@orthosirg.ucsf.edu. 2Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: coughlind@orthosurg.ucsf.edu. 3Orthofix, Inc., 3451 Plano Parkway, Lewisville, TX, 75056, USA. Electronic address: erikwaldorff@orthofix.com. 4Orthofix, Inc., 3451 Plano Parkway, Lewisville, TX, 75056, USA. Electronic address: jamesryaby@orthofix.com. 5Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: lotzj@orthosurg.ucsf.edu.1Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: millers@orthosirg.ucsf.edu. 2Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: coughlind@orthosurg.ucsf.edu. 3Orthofix, Inc., 3451 Plano Parkway, Lewisville, TX, 75056, USA. Electronic address: erikwaldorff@orthofix.com. 4Orthofix, Inc., 3451 Plano Parkway, Lewisville, TX, 75056, USA. Electronic address: jamesryaby@orthofix.com. 5Department of Orthopaedic Surgery, University of California, 513 Parnassus Ave, S-1161, Box 0514, San Francisco, CA, 94143, USA. Electronic address: lotzj@orthosurg.ucsf.edu.
Conference/Journal: Spine J.
Date published: 2015 Jan 15
Other: Pages: S1529-9430(16)00043-7 , Special Notes: doi: 10.1016/j.spinee.2016.01.003 , Word Count: 280



BACKGROUND CONTEXT:
Pulsed electromagnetic field (PEMF) therapies have been applied to stimulate bone healing and to reduce the symptoms of arthritis, but the effects of PEMF on intervertebral disc (IVD) biology is unknown.
PURPOSE:
The purpose of this study was to determine how PEMF affects gene expression of IVD cells in normal and inflammatory environments.
STUDY DESIGN/SETTING:
This was an in vitro human cell culture and microarray gene expression study.
METHODS:
Human annulus fibrosus (AF) and nucleus pulposus (NP) cells were separately encapsulated in alginate beads and exposed to IL-1α (10 ng/mL) to stimulate the inflammatory environment associated with IVD degeneration and/or stimulated by PEMF for four hours daily for up to seven days. RNA was isolated from each treatment group and analyzed via microarray to assess IL-1α- and PEMF-induced changes in gene expression. The study was funded in part by Orthofix, Inc. (approximately $200,000) and authors James T. Ryaby and Eric I. Waldorff are Orthofix, Inc. employees.
RESULTS:
Although PEMF treatment did not completely inhibit the effects of IL-1α, PEMF treatment lessened the IL-1α-induced upregulation of genes expressed in degenerated IVDs. Consistent with our previous results, after 4 days PEMF tended to reduce IL-1α-associated gene expression of IL-6 (25%, p = 0.07) in NP cells and MMP13 (26%, p = 0.10) in AF cells. Additionally, PEMF treatment significantly diminished IL-1α-induced gene expression of IL-17A (33%, p = 0.01) and MMP2 (24%, p = 0.006) in NP cells and NFκB (11%, p = 0.04) in AF cells.
CONCLUSIONS:
These results demonstrate that IVD cells are responsive to PEMF and motivate future studies to determine whether PEMF may be helpful for patients with IVD degeneration.
Copyright © 2016. Published by Elsevier Inc.
KEYWORDS:
Degeneration; IVD; Inflammation; Lower back pain; Matrix; PEMF
PMID: 26780754