title: Soybean isoflavones preserve bone mass in hindlimb-unloaded mice.
abstract: It is well known that skeletal unloading induces bone loss. It has been shown that soybean isoflavones are effective in preventing bone loss in osteoporotic animals. We investigated the ability of isoflavones to protect bone loss induced by hindlimb unloading by using a tail-suspension mouse model. Eight-week-old female mice were divided into five groups: (1) normal housed group (Normal), (2) sham unloaded group fed a control diet (Sham-UL), (3) hindlimb unloaded group fed a control diet (UL-C), (4) hindlimb unloaded group fed a 0.25% isoflavone conjugates diet (UL-ISO 0.25), and (5) hindlimb unloaded group fed a 0.5% isoflavone conjugates diet (UL-ISO 0.5). After 3 weeks, bone mineral density (BMD) of the femur was significantly decreased in UL-C, and this bone loss was prevented by isoflavone treatment. Histomorphometric analysis revealed a decrease in the cancellous bone of the distal femur in the UL-C group, and isoflavone prevented this change. Serum corticosterone increased in the UL-C group, and isoflavones inhibited the elevation. These results suggest that isoflavones might be promising food components that provide protection from bone loss and normalize stress-induced serum corticosterone during skeletal unloading.
authors.affiliation: Division of Applied Food Research, National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8636, Japan.
authors.forename: Fumie
authors.initials: F
authors.lastname: Sugiyama
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
authors.forename: Maiko
authors.initials: M
authors.lastname: Fujioka
authors.forename: Junko
authors.initials: J
authors.lastname: Ezaki
authors.forename: Ken
authors.initials: K
authors.lastname: Takeda
authors.forename: Chisato
authors.initials: C
authors.lastname: Miyaura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Ishida
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Yamada
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ishimi
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood; D005260:Female; D006614:Hindlimb / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D007529:Isoflavones / Q000097:blood / Q000494:pharmacology*; D008159:Lumbar Vertebrae / Q000187:drug effects; D051379:Mice; D011859:Radiography; D013025:Glycine max / Q000737:chemistry*; D016474:Weight-Bearing
chemical_list: D007529:Isoflavones; C004742:daidzein; D003345:Corticosterone