Effects of electromagnetic fields on bone loss in hyperthyroidism rat model.

Author: Liu C1, Zhang Y1, Fu T1, Liu Y1, Wei S1, Yang Y1, Zhao D1, Zhao W2, Song M3, Tang X4, Wu H1
Affiliation: <sup>1</sup>Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. <sup>2</sup>Navy University of Engineering, Wuhan, China. <sup>3</sup>Department of Gynaecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. <sup>4</sup>Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Conference/Journal: Bioelectromagnetics.
Date published: 2016 Dec 14
Other: Special Notes: doi: 10.1002/bem.22022. [Epub ahead of print] , Word Count: 234


Optimal therapeutics for hyperthyroidism-induced osteoporosis are still lacking. As a noninvasive treatment, electromagnetic fields (EMF) have been proven to be effective for treating osteoporosis in non-hyperthyroidism conditions. We herein systematically evaluated the reduced effects of EMF on osteoporosis in a hyperthyroidism rat model. With the use of Helmholtz coils and an EMF stimulator, 15 Hz/1 mT EMF was generated. Forty-eight 5-month-old male Sprague-Dawley rats were randomly divided into four different groups: control, levothyroxine treated (L-T4), EMF exposure + levothyroxine (EMF + L-T4), and EMF exposure without levothyroxine administration (EMF). All rats were treated with L-T4 (100 mg/day) except those in control and EMF groups. After 12 weeks, the results obtained from bone mineral density analyses and bone mechanical measurements showed significant differences between L-T4 and EMF + L-T4 groups. Micro CT and bone histomorphometric analyses indicated that trabecular bone mass and architecture in distal femur and proximal tibia were augmented and restored partially in EMF + L-T4 group. In addition, bone thyroid hormone receptors (THR) expression of hyperthyroidism rats was attenuated in EMF + L-T4 group, compared to control group, which was not observed in L-T4 group. According to these results, we concluded that 15 Hz/1 mT EMF significantly inhibited bone loss and micro architecture deterioration in hyperthyroidism rats, which might occur due to reduced THR expression caused by EMF exposure. Bioelectromagnetics. 2016;9999:XX-XX. © 2016 Wiley Periodicals, Inc.

© 2016 Wiley Periodicals, Inc.

KEYWORDS: bone metabolism; electromagnetic field; hyperthyroidism; osteoporosis; thyroid hormone receptor

PMID: 27973686 DOI: 10.1002/bem.22022