Synergistic effect of pulsed electromagnetic fields and saffron extract on osteogenic differentiation of bone marrow mesenchymal stem cells

Abstract

Introduction: Pulsed electromagnetic fields (PEMFs) are usually used to treat non-union fractures. Saffron is a medicinal plant with various pharmacologic effects. In the present study, the synergistic effect of PEMF and saffron aqueous extract on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) was evaluatedMethods: BMSCs were isolated from rat femur. After purification, the cells were divided into four groups including control group (did not receive any treatment), saffron alone (800 μg/mL), PEMF alone (50 Hz, 3 times a weak, 2 hours for every time, for 2 weeks), and saffron plus PEMF. Cytotoxicity was measured using MTT assay. After calculating the IC50 value for saffron extract (1.5 mg/mL), a lower concentration (800 μg/mL) was combined with PEMF. The differentiation of each cell group was evaluated using alkaline phosphatase (ALP) enzyme activity, alizarin red staining and reverse transcribed polymerase chain reaction (RT-PCR) method.Results: Saffron aqueous extract decreased dose-dependently the cell viability but the PEMF had not any significant effects on cell viability. The PEMF, saffron extract and their combination increased the ALP activity on day 10 but the increase was significant in synergist group. Alizarin red staining showed that mineralization groups were higher at day 14. RT-PCR results demonstrated that on the day 14 the group treated with both PEMF and saffron expressed osteogenic genes.Conclusion: Saffron extract combined with PEMFs could promote osteogenesis at the initial stage (the commitment of undifferentiated mesenchymal stem cells into osteoblast), hence, its usage might be beneficial in these patients

Keywords: Osteogenesis, Saffron, Pulsed electromagnetic fields, Differentiation