title: Pulsed Electromagnetic Field (PEMF) plus BMP-2 upregulates intervertebral disc-cell matrix synthesis more than either BMP-2 alone or PEMF alone.
abstract: METHODS
  An in vitro study using human intervertebral disc (IVD) cells.
  
  
  OBJECTIVE
  To determine if pulsed electromagnetic field (PEMF) plus bone morphogenetic protein (BMP)-2 could upregulate IVD-cell matrix synthesis more than either BMP-2 alone or PEMF alone.
  
  
  BACKGROUND
  BMP-7 and BMP-2 can both upregulate IVD-cell matrix synthesis. There are problems associated with using either BMP-2 or BMP-7. They can diffuse away rather quickly after injection into the IVD space, they cost a lot, and they have side effects such as soft-tissue inflammation and swelling. PEMF has been reported to stimulate various types of cells. PEMF is safe, inexpensive, and noninvasive, thus multiple use is possible. However, PEMF alone has a rather weak effect on disc cells. We decided to carry out an experiment whereby we combined PEMF with BMP-2. Our thoughts were that BMP-2 plus PEMF could be better than either alone.
  
  
  METHODS
  The PEMF signal used was similar to that used in the clinical treatment of fracture nonunions or delayed fracture healing. Human disc cells were treated with BMP-2 alone or PEMF alone or PEMF plus BMP-2. Quantitative real-time PCR was performed to determine mRNA expression levels of aggrecan, collagen-2, transforming growth factor (TGF)-β, BMP-2, and BMP-7. Sulfated glycosaminoglycansynthesis was analyzed using the dimethylmethylene blue method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7.
  
  
  RESULTS
  PEMF plus BMP-2 upregulates IVD-cell matrix synthesis more than BMP-2 alone or PEMF alone, and the effect seems to be synergistic. Also, PEMF plus BMP-2 induces more endogenous BMP-7 and BMP-2 mRNA levels as well as protein levels, as compared with either PEMF alone or BMP-2 alone.
  
  
  CONCLUSIONS
  PEMF plus BMP-2 acts in synergy to upregulate intervertebral disc-cell matrix synthesis more than either BMP-2 alone or PEMF alone.
authors.affiliation: Atlanta Veterans Affairs Medical Center, Decatur, GA, USA. motohiro2doctor@yahoo.co.jp
authors.forename: Motohiro
authors.initials: M
authors.lastname: Okada
authors.forename: Jin Hwan
authors.initials: JH
authors.lastname: Kim
authors.forename: Sangwook Tim
authors.initials: ST
authors.lastname: Yoon
authors.forename: William C
authors.initials: WC
authors.lastname: Hutton
mesh_terms: D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D055419:Bone Morphogenetic Protein 7 / Q000235:genetics / Q000378:metabolism; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D004574:Electromagnetic Fields; D005109:Extracellular Matrix / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007403:Intervertebral Disc / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D053674:Aggrecans; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D024043:Collagen Type II; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta