title: The effects of fructo-oligosaccharides in combination with soy protein on bone in osteopenic ovariectomized rats.
abstract: OBJECTIVE
  The intestinal microflora is important in rendering soy isoflavones bioavailable by facilitating their conversion to equol. Hence, substances that can modulate the intestinal microflora could affect the bioavailability of isoflavones. In this study, we examined the effects of fructo-oligosaccharides (FOS), a prebiotic, on enhancing the effects of soy isoflavones on bone in ovariectomized osteopenic female rats.
  
  
  METHODS
  Sixty-three 9-month-old female Sprague-Dawley rats were either sham-operated (Sham; one group) or ovariectomized (Ovx; four groups) and were fed a control diet for 3 months to induce bone loss. After bone loss was confirmed via dual-energy x-ray absorptiometry, rats were placed on dietary treatment for 4 months. The Sham and one Ovx group received a control diet, and the remaining Ovx groups received either a soy protein-based diet (Soy), a FOS-supplemented diet (FOS), or a soy protein-based and FOS-supplemented diet (Soy+FOS). Before the termination of the study, whole-body bone mineral density (BMD) and bone mineral content (BMC) were assessed under anesthesia. Immediately after euthanasia, bone specimens were collected for the assessments of BMD, BMC, and biomechanical and microarchitectural properties.
  
  
  RESULTS
  Whole-body BMD values were significantly higher in FOS and Soy+FOS groups compared with Ovx controls. The tibial BMC increased by 10%, 6%, and 4% in Soy, FOS, and Soy+FOS groups, respectively, compared to the Ovx control group. FOS and FOS+Soy treatments had the most pronounced effects in enhancing lumbar BMC and BMD. The FOS+Soy combination effectively improved tibial microarchitectural properties by enhancing trabecular number and lowering trabecular separation compared with Ovx controls. The effects of dietary treatments on lumbar microarchitectural properties were minimal and biomechanical properties of the femur were not affected by any of the dietary treatments.
  
  
  CONCLUSIONS
  Our findings suggest that, although incorporation of either soy or FOS in the diet of Ovx rats can improve BMD of the whole body, tibiae, and lumbar vertebrae, their combination had no any additive effects. However, in terms of microarchitecture, the combination of soy and FOS had a greater effect in reversing the loss of certain microarchitectural parameters such as tibial trabecular number, separation, and thickness.
authors.affiliation: Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL 32306, USA.
authors.forename: Latha
authors.initials: L
authors.lastname: Devareddy
authors.forename: Dania A
authors.initials: DA
authors.lastname: Khalil
authors.forename: Kiranmayi
authors.initials: K
authors.lastname: Korlagunta
authors.forename: Shirin
authors.initials: S
authors.lastname: Hooshmand
authors.forename: Danielle D
authors.initials: DD
authors.lastname: Bellmer
authors.forename: Bahram H
authors.initials: BH
authors.lastname: Arjmandi
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D015519:Bone Density / Q000187:drug effects; D019587:Dietary Supplements; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D015914:Estrogen Replacement Therapy; D005260:Female; D005269:Femur / Q000187:drug effects* / Q000502:physiology; D005632:Fructose / Q000494:pharmacology; D009844:Oligosaccharides / Q000494:pharmacology; D010024:Osteoporosis / Q000188:drug therapy; D010052:Ovariectomy; D048789:Phytoestrogens / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D008517:Phytotherapy; D019936:Probiotics / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D030262:Soybean Proteins / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D009844:Oligosaccharides; D048789:Phytoestrogens; D030262:Soybean Proteins; D005632:Fructose