Pulsed electromagnetic fields prevent osteoporosis in an ovariectomized female rat model: A prostaglandin E₂‐associated process

Abstract

With the use of Helmholtz coils and pulsed electromagnetic field (PEMF) stimulators to generate uniform time varying electromagnetic fields, the effects of extremely low frequency electromagnetic fields on osteoporosis and serum prostaglandin E(2) (PGE(2)) concentration were investigated in bilaterally ovariectomized rats. Thirty-five 3 month old female Sprague-Dawley rats were randomly divided into five different groups: intact (INT), ovariectomy (OVX), aspirin treated (ASP), PEMF stimulation (PEMF + OVX), and PEMF stimulation with aspirin (PEMF + ASP) groups. All rats were subjected to bilateral ovariectomy except those in INT group. Histomorphometric analyses showed that PEMF stimulation augmented and restored proximal tibial metaphyseal trabecular bone mass (increased hard tissue percentage, bone volume percentage, and trabecular number) and architecture (increased trabecular perimeter, trabecular thickness, and decreased trabecular separation) in both PEMF + OVX and PEMF + ASP. Trabecular bone mass of PEMF + OVX rats after PEMF stimulation for 30 days was restored to levels of age matched INT rats. PEMF exposure also attenuated the higher serum PGE(2) concentrations of OVX rats and restored it to levels of INT rats. These experiments demonstrated that extremely low intensity, low frequency, single pulse electromagnetic fields significantly suppressed the trabecular bone loss and restored the trabecular bone structure in bilateral ovariectomized rats. We, therefore, conclude that PEMF may be useful in the prevention of osteoporosis resulting from ovariectomy and that PGE(2) might relate to these preventive effects.

The Effects of Radiation on Bone Mineral Density of Radiology Workers Depending on The Device They Use

“…MRI device, works with radio frequency (RF) radiation and it causes electromagnetic field radiation. In literature, low frequency electromagnetic wave is used in order to heal bone fractures and to increase bone mineral density (11,12). But in these studies, it has been showed that electromagnetic wave is used in medicine by low frequency and pulse (15-72 Hz) (13).…”

The Effect of GSM Mobile Phone Electromagnetic Field on Femur Fracture Healing in a Rat Model

“…In other experimental studies, EM radiation of 0.4 T for 30 minutes a day for 30 days at 15 MHz and 8 MHz was found to have a beneficial effect on osteoporosis [11]. A regulatory effect of EM radiation (2 hours per day for 9 days) on trabecular bone structure in bilateral oopherectomised rats was found by Chang and Chang [10]. Tsai et al reported stimulation of human mesenchymal stem cells (hMSCs) by rectangular pulse PEMF radiation (7.5 Hz for 2 hours per day for 14 days) [24].…”

“…Our results were perhaps not as good as they could have been, had we exposed the rats to longer periods (more than one hour) of EM radiation per day, or for more days (longer than seven days), or at a lower frequency (less than 900 MHz). We used 900 Mhz because that is a standard transmission frequency of mobile telephones, but it is much higher than the frequencies of EM radiation used in experimental healing research, for example, in the studies by Chang, Zhang and Tsai [10,11,39]. Low frequency electromagnetic radiation may have more therapeutic potential in fracture healing than high frequency EM radiation [11,22,23].…”

“…When postmenopausal women were treated with free-transition magnetic waves (12 minutes a day for 30 days, then 24 minutes a day for 150 days), an increase in osteocalcin, procollagen, estrone, and estradiol levels; a decrease in serum total and partially ionized calcium levels; and an improvement in DXA values were observed [9]. EM radiation at a frequency of 15 Hz in pulse form has a therapeutic effect on osteoporosis [10]. Chang and Chang suggested that pulse EM radiation has a regulatory effect on trabecular bone structure by decreasing the loss of trabecular bone tissue in an experimental model in bilateral oopherectomised rats [10].…”

“…EM radiation at a frequency of 15 Hz in pulse form has a therapeutic effect on osteoporosis [10]. Chang and Chang suggested that pulse EM radiation has a regulatory effect on trabecular bone structure by decreasing the loss of trabecular bone tissue in an experimental model in bilateral oopherectomised rats [10]. Zhang et al reported an increase in mean bone mineral density in osteoporotic rats after EM radiation treatments at a frequency of 8.0 Hz and a magnetic power of 0.4 T for 30 minutes a day for 30 days [11].…”