Simultaneous effect of nitric oxide and electromagnetic field on the proliferation rate and morphology of stromal stem cells

Aim: Electromagnetic field as a physical stimulus, willingly or unwillingly are affected cellular processes. In this study morphology changing and proliferation rate of mesenchymal stem cells were investigated in presence of electromagnetic field (EMF) and nitric oxide (NO).
Material and The stromal stem cells were isolated from the Rat bone marrow and incubated. After several passages of the harvested cells, Deta-NO as a donor of nitric oxide was then added to cell culture. These cells were also treated by EMF (50 Hz and 20 mT). The MTT test was used for estimating proliferation rate of the cells. To estimate the proportion of the cell line in different phases of cell cycle due to treatment with NO and EMF, cellular DNA contents were measured by flow cytometry.
The results demonstrated decreasing proliferation rate of the stem cells exposed with EMF and NO compared with the control group. We found that the rate of decrease is highly related to the concentration of NO. The double treatment of EMF and nitric oxide was yielded to an obvious arrest in the cell cycle at G2/M phase. Nitric oxide associated with EMF also changed the cell morphology and increased the cell motilities.
The changing of cell morphology and reduction of proliferation rate of the stem cell can be considered as a symptom showing the beginning of cell differentiation.