title: Estrogen-mimicking isoflavone genistein prevents bone loss in a rat model of obstructive sleep apnea-hypopnea syndrome.
abstract: OBJECTIVE
  Intermittent hypoxia was introduced to mimic obstructive sleep apnea-hypopnea syndrome (OSAHS) in rats. Then, bone mass, bone strength and bone turnover were evaluated, and the influence of genistein on bone mass reduction was investigated in these rats.
  
  
  METHODS
  OSAHS animal model was established via chronic intermittent hypoxia, and genistein (2.5 mg/kg/day) was used to treat OSAHS rats. The bone mineral density (BMD), bone Histomorphometric indicators, bone biomechanics and expressions of genes related to bone formation and resorption (Runx2, Col I, ALP, Osteocalcin, OPG, RANKL and TRAP-5b) were measured after treatment.
  
  
  RESULTS
  The BMD in OSAHS+OVX group was significantly lower than that in OVX group (P<0.05). The BMD in OSAHS+OVX+Genistein group was markedly increased when compared with OSAHS+OVX group (P<0.05), accompanied by partial improvement of the OSAHS induced damage to the lumbar biomechanics. In OSAHS+OVX group, the expressions of Runx2, Col I, ALP and Osteocalcin were significantly reduced when compared with OVX group, and rats in OSAHS+OVX+Genistein group had significantly higher expressions of Runx2, Col I, ALP and Osteocalcin and reduced TRAP-5b expression as compared to OSAHS+OVX group (P<0.05).
  
  
  CONCLUSIONS
  Genistein can improve the reduction in bone mass and bone strength due to OSAHS in OVX rats, which may be attributed to the increase in bone formation and inhibition of bone resorption. Our findings suggest that genistein may be used to treat and prevent osteoporosis in postmenopausal women with OSAHS.
authors.affiliation: Department of Endocrinology, Tongji Hospital, Tongji University School of Medicine Shanghai 200065, China.
authors.forename: Lige
authors.initials: L
authors.lastname: Song
authors.affiliation: School of Basic Medical Sciences, Fudan University Shanghai 200433, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Liang
authors.affiliation: Department of Endocrinology, Tongji Hospital, Tongji University School of Medicine Shanghai 200065, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects; D001862:Bone Resorption / Q000378:metabolism* / Q000517:prevention & control*; D024042:Collagen Type I / Q000378:metabolism; D050659:Core Binding Factor Alpha 1 Subunit / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D019833:Genistein / Q000494:pharmacology / Q000627:therapeutic use*; D000860:Hypoxia / Q000378:metabolism; D015675:Osteocalcin / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects; D048789:Phytoestrogens / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000378:metabolism*
chemical_list: D024042:Collagen Type I; D050659:Core Binding Factor Alpha 1 Subunit; D048789:Phytoestrogens; C493717:Runx2 protein, rat; D015675:Osteocalcin; D019833:Genistein
keywords: Obstructive sleep apnea-hypopnea syndrome; bone loss; genistein; hypoxia