title: Daidzein improves insulin resistance in ovariectomized rats.
abstract: OBJECTIVE
  To determine whether daidzein improves insulin resistance by modifying weight gain, visceral fat accumulation, blood lipids and serum cytokines levels in ovariectomized Sprague-Dawley rats.
  
  
  METHODS
  Twenty-eight 12-week-old female rats were divided into three groups: the sham-operated group (SHAM) (n =10), the ovariectomized group receiving daidzein therapy (DAID) (n =10), and the ovariectomized control group (Control) (n =8). The rats in the DAID group received 50 mg/kg daidzein via gavage daily. Weight and food intake were recorded every 2 weeks. All of the animals were euthanized 12 weeks after ovariectomy, after which their fasting insulin, glucose, blood lipids, estradiol, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), adiponectin and leptin levels were measured.
  
  
  RESULTS
  After 12 weeks, the ovariectomized rats demonstrated an increase in their body weight and visceral fat; compared to the SHAM rats, the ovariectomized rats also experienced a significant increase in their serum IL-6 levels and insulin resistance, which was calculated using the homeostatic model assessment of insulin resistance (HOMA-IR) (p <0.05). Daidzein therapy decreased weight gain, visceral fat, the HOMA-IR index and IL-6 levels that were induced by ovariectomy. Rats which had received daidzein therapy had lower levels of TNF-α, leptin and blood lipids (except for high density lipoprotein cholesterol) than the other two groups. IL-6 levels positively correlated with the HOMA-IR index in all of the rats after adjustment for body weight (r =0.495; p =0.016).
  
  
  CONCLUSIONS
  We conclude that daidzein can improve insulin resistance induced by ovariectomy by decreasing weight gain, visceral fat accumulation, blood lipids, TNF-α, leptin and IL-6 levels.
authors.affiliation: Department of Gynecology, Obstetrics & Gynecology Hospital of Fudan University, Shanghai, China.
authors.forename: Y K
authors.initials: YK
authors.lastname: Cao
authors.forename: S F
authors.initials: SF
authors.lastname: Zhang
authors.forename: S E
authors.initials: SE
authors.lastname: Zou
authors.forename: X
authors.initials: X
authors.lastname: Xia
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D007333:Insulin Resistance; D015850:Interleukin-6 / Q000097:blood; D050152:Intra-Abdominal Fat / Q000187:drug effects; D007529:Isoflavones / Q000494:pharmacology*; D020738:Leptin / Q000097:blood; D010052:Ovariectomy; D048789:Phytoestrogens / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D015430:Weight Gain / Q000187:drug effects
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D015850:Interleukin-6; D007529:Isoflavones; D020738:Leptin; D048789:Phytoestrogens; D014280:Triglycerides; D014409:Tumor Necrosis Factor-alpha; C004742:daidzein