Changes in polyamines, c‐myc and c‐fos gene expression in osteoblast‐like cells exposed to pulsed electromagnetic fields

Abstract

Pulsed electromagnetic field (PEMF) stimulation promotes the healing of fractures in humans, though its effect is little known. The processes of tissue repair include protein synthesis and cell differentiation. The polyamines (PA) are compounds playing a relevant role in both protein synthesis processes and cell differentiation through c-myc and c-fos gene activation. Since several studies have demonstrated that PEMF acts on embryonic bone cells, human osteoblast-like cells and osteosarcoma TE-85 cell line, in this study we analyzed the effect on cell PAs, proliferation, and c-myc and c-fos gene expression of MG-63 human osteoblast-like cell cultures exposed to a clinically useful PEMF. The cells were grown in medium with 0.5 or 10% fetal calf serum (FCS). c-myc and c-fos gene expressions were determined by RT-PCR. Putrescine (PUT), spermidine (SPD), or spermine (SPM) levels were evaluated by HPLC. [(3)H]-thymidine was added to cultures for DNA analysis. The PEMF increased [(3)H]-thymidine incorporation (P < or = .01), while PUT decreased after treatment (P < or = .01); SPM and SPD were not significantly affected. c-myc was activated after 1 h and downregulated thereafter, while c-fos mRNA levels increased after 0.5 h and then decreased. PUT, SPD, SPM trends, and [(3)H]-thymidine incorporation were significantly related to PEMF treatment. These results indicate that exposure to PEMF exerts biological effects on the intracellular PUT of MG-63 cells and DNA synthesis, influencing the genes encoding c-myc and c-fos gene expression. These observations provide evidence that in vitro PEMF affects the mechanisms involved in cell proliferation and differentiation.

Involvement of mitochondrial activity in mediating ELF‐EMF stimulatory effect on human sperm motility

“…The ELF-EMFs have been found to produce a variety of biological effects, from simple enzyme reactions to the far more complex gene induction and protein [Goodman and Blank, 1998;De Mattei et al, 2005;Delle Monache et al, 2008;Piacentini et al, 2008;Goodman et al, 2009]. Recently, studies carried out on mammalian sperm suggest that ELF-EMFs can negatively [Bernabò et al, 2007] or positively [Iorio et al, 2007;Roychoudhury et al, 2009] influence sperm motility according to the specific characteristics of the EMF applied and/or to the type of sperm used.…”

Microwave Irradiation Affects Gene Expression in Plants

“…Two aspects of these biological experiments need special attention: the organism itself and the parameter, preferably a molecular marker, 8 to be studied. Plants may be appropriate experimental subjects, in the sense that they are highly sensitive to environmental signals [9][10][11] and plant studies raise less emotional concern than studies on animals or humans.…”

The Effect of Spatially Inhomogeneous Electromagnetic Field and Local Inductive Hyperthermia on Nonlinear Dynamics of the Growth for Transplanted Animal Tumors

“…It should be noted, that pulsed asymmetric EF and heat shock produced different patterns of polypeptide synthesis (Goodman & Henderson, 1988). Inhomogeneous pulsing EF caused significant reductions in osteoclast formation of tumor necrosis factors, interleukins (Chang et al, 2004) and in osteoblast-like cell of proliferation and gene expression (De Mattei et al, 2005). These observations provide evidence that in vitro inhomogeneous EF affects the mechanisms involved in cell proliferation and differentiation.…”