ABSTRACT
Objective:To explore the effect of repeated magnetic stimulation (rMS) on the growth and differentiation of SH-SY5Y human neuroblastoma cells.Methods:SH-SY5Y cells were subjected to rMS at 15%, 30% and 60% of the maximum output intensity at frequencies of 0.5Hz, 1Hz, 5Hz, 10Hz and 20Hz. They received either 800 or 1600 pulses per day for 4 days. Cell viability was detected using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. Apoptosis was induced using 1-methyl-4-phenylpyridine ion (MPP + ) and all-trans retinoic acid was used to induce differentiation. The expression of neuron-specific nuclear proteins and the degree of cell differentiation were observed by immunohistochemistry. Results:0.5Hz rMS inhibited proliferation and 10Hz rMS promoted it. With 5Hz rMS significantly greater cell proliferation was observed at 15% and 30% of the maximum output intensity. The stimulatory effect of 1600 pulses per day was significantly greater than that of 800 pulses, especially at 10Hz. Apoptosis was inhibited at both 0.5Hz and 10Hz with 30% of the maximum output intensity. Meanwhile, both 0.5Hz and 10Hz rMS promoted differentiation of the SH-SY5Y cells into neurons.Conclusions:rMS at low frequency inhibits the proliferation of SH-SY5Y cells, but at higher frequency it promotes it. The effect strengthens with more pulses administered. rMS has a protective effect on MPP + -induced SH-SY5Y apoptosis, and it can promote the cells′ differentiation into neurons.