title: Pulsed electromagnetic field ameliorates cartilage degeneration by inhibiting mitogen-activated protein kinases in a rat model of osteoarthritis.
abstract: OBJECTIVE
  We assessed the effects of pulsed electromagnetic field (PEMF) on cartilage degeneration, and expression of mitogen-activated protein kinases (MAPKs) and matrix metalloproteinases (MMPs), in an experimental rat model of osteoarthritis induced by anterior cruciate ligament transection (ACLT).
  
  
  METHODS
  Experimental.
  
  
  METHODS
  University animal laboratory.
  
  
  METHODS
  30 male Sprague-Dawley rats.
  
  
  METHODS
  We performed histological examination, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, to assess cartilage degeneration, urine C-terminal cross-linking telopeptide of type II collagen (CTX-II), and mRNA expression of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (c-Jun), p38, and MMPs.
  
  
  RESULTS
  Urinary CTX-II in the PEMF group was significantly lower than in the ACLT group at 9 and 13 weeks. Mankin scores in the PEMF group significantly lower than that in the ACLT group (P < 0.01). mRNA expression of ERK1, c-Jun, p38, MMP-13 and MMP-3 was significantly higher in the ACLT group than in the Sham group, while that with the sole exception of MMP-3 in the PEMF group was significantly lower than in the ACLT group.
  
  
  CONCLUSIONS
  PEMF may regulate the catabolic factor, MMP13, and inhibit cartilage destruction, at least partially, by inhibiting MAPKs signaling pathway.
authors.affiliation: Department of Rehabilitation, The First Affiliated Hospital of University of South China, Hengyang, Hunan, People's Republic of China. Electronic address: zhoujun8005@163.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Rehabilitation, The First Affiliated Hospital of University of South China, Hengyang, Hunan, People's Republic of China; Clinical Medical College of Acupuncture Moxibustion and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Rehabilitation, The First Affiliated Hospital of University of South China, Hengyang, Hunan, People's Republic of China.
authors.forename: Haitao
authors.initials: H
authors.lastname: Xie
authors.affiliation: Department of Rehabilitation, The First Affiliated Hospital of University of South China, Hengyang, Hunan, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Rehabilitation, West China Hospital, Sichuan University, Chengdu, Sichuan, People's Republic of China.
authors.forename: Huifang
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Rehabilitation, The First Affiliated Hospital of University of South China, Hengyang, Hunan, People's Republic of China.
authors.forename: Yahua
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Department of Rehabilitation, The First Affiliated Hospital of University of South China, Hengyang, Hunan, People's Republic of China.
authors.forename: Neng
authors.initials: N
authors.lastname: Li
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism / Q000528:radiation effects*; D024043:Collagen Type II / Q000652:urine; D004195:Disease Models, Animal; D004574:Electromagnetic Fields; D004797:Enzyme-Linked Immunosorbent Assay; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000528:radiation effects; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism / Q000528:radiation effects*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism / Q000528:radiation effects*; D010003:Osteoarthritis / Q000378:metabolism / Q000517:prevention & control*; D010446:Peptide Fragments / Q000652:urine; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D024043:Collagen Type II; D010446:Peptide Fragments; D012333:RNA, Messenger; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D053509:Matrix Metalloproteinase 13; C507083:Mmp13 protein, rat
keywords: Mitogen-activated protein kinases; Osteoarthritis; Pulsed electromagnetic field