Pulsed electromagnetic field ameliorates cartilage degeneration by inhibiting mitogen-activated protein kinases in a rat model of osteoarthritis

Objectives: 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). Design: Experimental. Setting: University animal laboratory. Participants: 30 male Sprague Dawley rats. Main Outcome Measures: 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-11 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. 2016 Elsevier Ltd. All rights reserved.