title: Feeding soy protein isolate and oils rich in omega-3 polyunsaturated fatty acids affected mineral balance, but not bone in a rat model of autosomal recessive polycystic kidney disease.
abstract: BACKGROUND
  Polycystic kidney disease (PKD), a genetic disorder characterized by multiple cysts and renal failure at an early age. In children, kidney disease is often accompanied by disordered mineral metabolism, failure to achieve peak bone mass, and reduced adult height. Optimizing bone health during the growth stage may preserve against bone loss associated with early renal dysfunction in PKD. Dietary soy protein and omega-3 polyunsaturated fatty acid (n-3 PUFA) have been reported to ameliorate PKD and to promote bone health. The study objective was to determine the bone effects of feeding soy protein and/or n-3 PUFAs in a rat model of PKD.
  
  
  METHODS
  Weanling female PCK rats (n = 12/group) were randomly assigned to casein + corn oil (Casein + CO), casein + soybean oil (Casein + SO), soy protein isolate + soybean oil (SPI + SO) or soy protein isolate + 1:1 soybean oil:salmon oil blend (SPI + SB) for 12 weeks.
  
  
  RESULTS
  Rats fed SPI + SO diet had shorter (P = 0.001) femur length than casein-fed rats. Rats fed SPI + SO and SPI + SB diet had higher (P = 0.04) calcium (Ca) and phosphorus (P) retention. However, there were no significant differences in femur and tibial Ca, P or bone mass between diet groups. There were also no significant difference in bone microarchitecture measured by micro-computed tomography or bone strength determined by three-point bending test between diet groups.
  
  
  CONCLUSIONS
  Early diet management of PKD using SPI and/or n-3 PUFAs influenced bone longitudinal growth and mineral balance, but neither worsened nor enhanced bone mineralization, microarchitecture or strength.
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, 1038 Agricultural Sciences Bldg, P.O. Box 6108, Evansdale Campus, Morgantown, West Virginia, 26505, USA. kmaditz@mix.wvu.edu.
authors.forename: Kaitlin H
authors.initials: KH
authors.lastname: Maditz
authors.affiliation: Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, 74078, USA. bjsmith@okstate.edu.
authors.forename: Brenda J
authors.initials: BJ
authors.lastname: Smith
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, 1038 Agricultural Sciences Bldg, P.O. Box 6108, Evansdale Campus, Morgantown, West Virginia, 26505, USA. msm0037@tigermail.auburn.edu.
authors.forename: Matthew
authors.initials: M
authors.lastname: Miller
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, 1038 Agricultural Sciences Bldg, P.O. Box 6108, Evansdale Campus, Morgantown, West Virginia, 26505, USA. coldaker@mix.wvu.edu.
authors.forename: Chris
authors.initials: C
authors.lastname: Oldaker
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, 1038 Agricultural Sciences Bldg, P.O. Box 6108, Evansdale Campus, Morgantown, West Virginia, 26505, USA. janet.tou@mail.wvu.edu.
authors.forename: Janet C
authors.initials: JC
authors.lastname: Tou
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000818:Animals; D015519:Bone Density / Q000502:physiology*; D004195:Disease Models, Animal; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005260:Female; D006706:Homeostasis / Q000502:physiology; D008903:Minerals / Q000378:metabolism; D015675:Osteocalcin / Q000378:metabolism*; D017044:Polycystic Kidney, Autosomal Recessive / Q000000981:diagnostic imaging / Q000178:diet therapy*; D011897:Random Allocation; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012680:Sensitivity and Specificity; D030262:Soybean Proteins / Q000008:administration & dosage*; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D015525:Fatty Acids, Omega-3; D008903:Minerals; D030262:Soybean Proteins; D015675:Osteocalcin