title: [The study of genistein attenuating genioglossus muscle fatigue under chronic intermittent hypoxia].
abstract: OBJECTIVE
  To investigate the effects of genistein on genioglossus muscle function and nuclear factor erythroid 2 related factor 2(Nrf-2)/antioxidant responsive element(ARE) signaling pathway in rats under chronic intermittent hypoxia(CIH) condition in order to find medication treatment of obstructive sleep apnea/hyponea syndrome.
  
  
  METHODS
  Thirty female Sprague-Dawley(SD) rats (8 weeks old) were randomly(random number table) divided into three groups 1 week after ovariectomy: control group(NC group), CIH group, and CIH+genistein treatment group(T group). Rats in the latter two groups were exposed to CIH for 8 h/d for 5 weeks. Electrophysiological method was used to detect the change of genioglossus muscle function, and real-time reverse transcription(RT)-PCR and Western blotting were used to determine the level of Nrf-2 gene and protein.
  
  
  RESULTS
  Compared to NC group, the contractive properties of genioglossus muscle fatigue test at every time set was significantly decreased in CIH group(P<0.05). Compared to CIH group, the contractive properties was significantly increased in T group(P<0.05). The level of Nrf-2 gene and protein were less in CIH group(0.54±0.11 and 0.35±0.13) than in NC group(1.00±0.001.00±0.00)(P<0.05). Compared to CIH group the level of Nrf-2 gene and protein were increased in T group (0.76 ± 0.16 and 0.63 ± 0.14) (P<0.05), however, it was still less than the level in NC group(P<0.05).
  
  
  CONCLUSIONS
  CIH attenuates genioglossus muscle fatigue resistance under chronic intermittent hypoxia through Nrf-2/ARE signaling pathway. Genistein protects genioglossus muscle function through up-regulation of the level of Nrf-2 gene and protein.
authors.affiliation: Department of Orthodontics, Hospital of Stomatology, College of Medicine, Zhejiang University, Hangzhou 310006, China.
authors.forename: W H
authors.initials: WH
authors.lastname: Ding
authors.forename: W
authors.initials: W
authors.lastname: Li
authors.forename: X Y
authors.initials: XY
authors.lastname: Chen
authors.forename: J J
authors.initials: JJ
authors.lastname: Shi
mesh_terms: D000818:Animals; D000975:Antioxidants; D002908:Chronic Disease; D005260:Female; D019833:Genistein / Q000494:pharmacology*; D000860:Hypoxia / Q000188:drug therapy*; D018763:Muscle Fatigue / Q000187:drug effects* / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D051267:NF-E2-Related Factor 2 / Q000235:genetics / Q000378:metabolism*; D010052:Ovariectomy; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020181:Sleep Apnea, Obstructive / Q000188:drug therapy*; D014059:Tongue / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D015854:Up-Regulation
chemical_list: D000975:Antioxidants; D051267:NF-E2-Related Factor 2; D019833:Genistein