Exposing Differentiated Osteoblast-Like MC3T3-E1 Cells to Extremely Low-Frequency Electric Fields Has Calcification-Promoting Effects

In this study, the first to investigate the potential of using extremely low-frequency electric fields (ELFEFs) to improve osteoporosis, we examined the effects of ELFEF exposure on bone formation using osteoblast-like MC3T3-E1 cells. We first constructed a system to regulate the intensity of the ELFEF exposure. Next, we used this system to examine the effect of ELFEF exposure on the proliferation of undifferentiated and differentiated MC3T3-E1 cells. ELFEF exposure increased calcium deposition in an intensity-dependent manner. In addition to increasing alkaline phosphatase (ALP) activity and collagen production, ELFEF exposure also stimulated mRNA expression of osteoblast markers Col1a1, Alpa, Sp7, and Dlx5 in an intensity-dependent manner. In contrast, ELFEF exposure did not enhance RANKL expression. These results indicate that ELFEF exposure has potential for application in the prevention and/or improvement of bone fragility.