In vitro effects of PEMFs on bone cell cultures of normal and osteopenic rat

The aim of this study was to examine the effects of low-frequency, low-ener gy pulsed electromagnetic fields (PEMFs) on cell proliferation and differen tiation in rat osteoblast primary cultures. Cells were obtained from normal and osteopenic rat bone and were named NE and OB, respectively. The osteob lastic phenotype was assessed by stimulation with 1,25(OH2) vitamin D-3. NE and OB cells were seeded in multiwell plates and exposed to PEMFs for two different periods. Control cultures of both groups were incubated under the same conditions, with the pulse generator off. Assessment of PEMF effects was performed for the following parameters for each culture: alkaline phosp hatase (ALP) activity, osteocalcin level, and MTT test. Results showed that OB and NE cell proliferation was significantly improved (p < 0.03, p = 0.0 4 respectively) after 48 h of PEMF exposure. Osteocalcin production of OB a fter 5 days of PEMF exposure was significantly higher than normal (p = 0.00 7) and osteopenic (p = 0.033) bone-derived controls. These results show tha t PEMFs act on osteopenic bone-derived osteoblasts, stimulating proliferati on of cells and then, after a longer exposure, activating them.