title: Effects of electromagnetic fields on bone loss in hyperthyroidism rat model.
abstract: 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. 38:137-150, 2017. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Chaoxu
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yingchi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Fu
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wei
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Dongming
authors.initials: D
authors.lastname: Zhao
authors.affiliation: Navy University of Engineering, Wuhan, China.
authors.forename: Wenchun
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Department of Gynaecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Mingyu
authors.initials: M
authors.lastname: Song
authors.affiliation: Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Tang
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Wu
mesh_terms: D000818:Animals; D015519:Bone Density / Q000528:radiation effects; D004195:Disease Models, Animal; D005786:Gene Expression Regulation / Q000528:radiation effects; D006980:Hyperthyroidism / Q000097:blood / Q000150:complications* / Q000652:urine; D055909:Magnetic Field Therapy; D008297:Male; D010010:Osteoclasts / Q000473:pathology / Q000528:radiation effects; D010024:Osteoporosis / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011988:Receptors, Thyroid Hormone / Q000235:genetics; D013977:Tibia / Q000378:metabolism / Q000503:physiopathology / Q000528:radiation effects
chemical_list: D012333:RNA, Messenger; D011988:Receptors, Thyroid Hormone
keywords: bone metabolism; electromagnetic field; hyperthyroidism; osteoporosis; thyroid hormone receptor