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-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.