Proteoglycan synthesis in bovine articular cartilage explants exposed to different low-frequency low-energy pulsed electromagnetic fields.
OBJECTIVE
To investigate the role of pulsed electromagnetic field (PEMF) exposure parameters (exposure length, magnetic field peak amplitude, pulse frequency) in the regulation of proteoglycan (PG) synthesis of bovine articular cartilage explants.


METHODS
Bovine articular cartilage explants were exposed to a PEMF (75 Hz; 2 mT) for different time periods: 1, 4, 9, 24 h. Then, cartilage explants were exposed for 24 h to PEMFs of different magnetic field peak amplitudes (0.5, 1, 1.5, 2 mT) and different frequencies (2, 37, 75, 110 Hz). PG synthesis of control and exposed explants was determined by Na2-35SO4 incorporation.


RESULTS
PEMF exposure significantly increased PG synthesis ranging from 12% at 4 h to 17% at 24 h of exposure. At all the magnetic field peak amplitude values, a significant PG synthesis increase was measured in PEMF-exposed explants compared to controls, with maximal effect at 1.5 mT. No effect of pulse frequency was observed on PG synthesis stimulation.


CONCLUSIONS
The results of this study show the range of exposure length, PEMF amplitude, pulse frequency which can stimulate cartilage PG synthesis, and suggest optimal exposure parameters which may be useful for cartilage repair in in vivo experiments and clinical application.
De Mattei
M
M
Department of Morphology and Embryology, University of Ferrara, 44100 Ferrara, Italy. dmm@unife.it
Fini
M
M
Setti
S
S
Ongaro
A
A
Gemmati
D
D
Stabellini
G
G
Pellati
A
A
Caruso
A
A
D000818:Animals; D002358:Cartilage, Articular / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D002417:Cattle; D046508:Culture Techniques / Q000379:methods; D004574:Electromagnetic Fields; D011509:Proteoglycans / Q000378:metabolism* / Q000528:radiation effects
D011509:Proteoglycans