title: Soy isoflavones exert beneficial effects on letrozole-induced rat polycystic ovary syndrome (PCOS) model through anti-androgenic mechanism.
abstract: BACKGROUND
  Soy is the main source of phytoestrogens, which has long been used as traditional food. One major subtype of phytoestrogens includes isoflavones and they are scientifically validated for their beneficial actions on many hormone-dependent conditions.
  
  
  OBJECTIVE
  The present study examines the effect of soy isoflavones on letrozole-induced polycystic ovary syndrome (PCOS) rat model.
  
  
  METHODS
  PCOS was induced in Sprague-Dawley rats with of 1 mg/kg letrozole, p.o. once daily for 21 consecutive days. Soy isoflavones (50 and 100 mg/kg) was administered for 14 days after PCOS induction. Physical parameters (body weight, oestrous cycle determination, ovary and uterus weight) metabolic parameters (oral glucose tolerance test, total cholesterol), steroidal hormone profile (testosterone and 17β-oestradiol), steroidogenic enzymes (3β-hydroxy steroid dehydrogenase (HSD) and 17β-HSD), oxidative stress and histopathology of ovary were studied.
  
  
  RESULTS
  Soy isoflavones (100 mg/kg) treatment significantly altered the letrozole-induced PCOS symptoms as observed by decreased body weight gain (p < 0.05), percentage diestrous phase (p < 0.001), testosterone (p < 0.001), 3β-HSD (p < 0.01) and 17β-HSD (p < 0.001) enzyme activity and oxidative stress. Histological results reveal that soy isoflavones treatment in PCOS rats resulted in well-developed antral follicles and normal granulosa cell layer in rat ovary.
  
  
  CONCLUSIONS
  Treatment with soy isoflavones exerts beneficial effects in PCOS rats (with decreased aromatase activity) which might be due to their ability to decrease testosterone concentration in the peripheral blood.
  
  
  CONCLUSIONS
  Analysis of physical, biochemical and histological evidences shows that soy isoflavones may be beneficial in PCOS.
authors.affiliation: a Department of Pharmacology , PSG College of Pharmacy , Coimbatore , Tamil Nadu , India.
authors.forename: Ravi Kumar
authors.initials: RK
authors.lastname: Rajan
authors.affiliation: b Department of Pharmaceutical Analysis , PSG College of Pharmacy , Coimbatore , Tamil Nadu , India.
authors.forename: Siva Selva Kumar
authors.initials: SS
authors.lastname: M
authors.affiliation: a Department of Pharmacology , PSG College of Pharmacy , Coimbatore , Tamil Nadu , India.
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Balaji
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D000726:Androgen Antagonists / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000097:blood; D030762:Estrous Cycle / Q000187:drug effects; D005260:Female; D007529:Isoflavones / Q000302:isolation & purification / Q000494:pharmacology*; D000077289:Letrozole; D009570:Nitriles; D010053:Ovary / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects; D048789:Phytoestrogens / Q000302:isolation & purification / Q000494:pharmacology*; D008517:Phytotherapy; D010946:Plants, Medicinal; D011085:Polycystic Ovary Syndrome / Q000097:blood / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D017207:Rats, Sprague-Dawley; D013025:Glycine max / Q000737:chemistry*; D013739:Testosterone / Q000097:blood; D013997:Time Factors; D014230:Triazoles; D014599:Uterus / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D015430:Weight Gain / Q000187:drug effects
chemical_list: D000726:Androgen Antagonists; D000975:Antioxidants; D015415:Biomarkers; D001786:Blood Glucose; D007529:Isoflavones; D009570:Nitriles; D048789:Phytoestrogens; D014230:Triazoles; D013739:Testosterone; D004958:Estradiol; D000077289:Letrozole; D002784:Cholesterol; D015067:17-Hydroxysteroid Dehydrogenases; D015096:3-Hydroxysteroid Dehydrogenases
keywords: Genistein; daidzein; oestradiol; oestrogen beta; phytoestrogen; testosterone