title: The morphometry of materno-fetal oxygen exchange barrier in a baboon model of obesity.
abstract: BACKGROUND
  More than one-fourth of U.S. women are overweight; more than one-third are obese. Maternal obesity has been linked to an increased incidence of stillbirths, fetal macrosomia, fetal intrauterine growth restriction and pre-eclampsia. The placenta plays a key role in the nutrients and oxygen supply to the fetus. The data about structural changes in the placental villous membrane (VM), a major component of the feto-maternal nutrient and oxygen exchange barrier, during obesity are sparse and inconsistent. Our objective was to evaluate the morphometric changes in the placental exchange barrier in a baboon model of obesity.
  
  
  METHODS
  The previously described baboon model of maternal obesity was studied. We compared 4 obese to 4 non-obese baboons. Placental stereology with the use of transmission electron microscopy was performed to estimate VM oxygen diffusing capacities and morphometry.
  
  
  RESULTS
  The specific placental oxygen diffusing capacities per unit of fetal weight were similar in baboons and humans. Maternal leptin concentrations correlated negatively with placental basement membrane thickness (r = -0.78, p < 0.05), while fetal leptin levels correlated negatively with endothelial thickness of fetal capillaries (r = -0.78, p < 0.05). The total and specific villous membrane oxygen diffusing capacities were not different between the two groups.
  
  
  CONCLUSIONS
  To the best of our knowledge this is the first report of placental oxygen diffusing capacities and placental ultrastructural changes in a baboon model of obesity. Previously reported placental inflammation in maternal obesity is not associated with changes in the VM diffusing capacities and ultrastructure.
authors.affiliation: Department of Obstetrics and Gynecology, University of Tennessee Health Science Center, Memphis, TN, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Samson
authors.forename: G
authors.initials: G
authors.lastname: Mari
authors.forename: E J
authors.initials: EJ
authors.lastname: Dick
authors.forename: G B
authors.initials: GB
authors.lastname: Hubbard
authors.forename: R J
authors.initials: RJ
authors.lastname: Ferry
authors.forename: N E
authors.initials: NE
authors.lastname: Schlabritz-Loutsevitch
mesh_terms: D000818:Animals; D001837:Body Weights and Measures / Q000662:veterinary; D004195:Disease Models, Animal; D005260:Female; D020567:Fetal Weight / Q000502:physiology; D008431:Maternal-Fetal Exchange / Q000187:drug effects / Q000502:physiology*; D009765:Obesity / Q000378:metabolism* / Q000473:pathology; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D010215:Papio; D010920:Placenta / Q000378:metabolism / Q000473:pathology*; D021041:Placental Circulation / Q000502:physiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism* / Q000473:pathology
chemical_list: D010100:Oxygen