title: Fetal serum folate concentrations and placental folate transport in obese women.
abstract: OBJECTIVE
  We hypothesized that fetal folate serum concentrations are lower and placental folate transport is impaired in pregnancies of obese women.
  
  
  METHODS
  Umbilical vein serum and placental tissue were collected from normal weight and obese pregnant women at term. Cellular localization (immunohistochemistry) of folate receptor-α (FR-α), proton coupled folate transporter (PCFT), and reduced folate carrier (RFC) was established. Protein expression (Western blot) and transporter activity (isotope labeled methyltetrahydrofolate) were determined in syncytiotrophoblast microvillus membranes (MVM).
  
  
  RESULTS
  Fetal folate concentrations were similar in obese women as compared with normal weight women. Protein expression of FR-α in microvillus membranes was increased (+173%), in RFC was decreased (-41%), and in PCFT was unchanged. However, activity of FR-α, PCFT, and RFC was unaltered in obesity.
  
  
  CONCLUSIONS
  Fetal serum folate concentrations and placental folate transport activity are not altered in obesity at term, which suggests that limited availability of folate does not contribute to abnormal gene methylation and developmental programming.
authors.affiliation: Division of Maternal Fetal Medicine, University of Texas Health Science Center at San Antonio, Department of Obstetrics & Gynecology, San Antonio, TX 78229, USA. cartermf@uthscsa.edu.
authors.forename: Margaret F
authors.initials: MF
authors.lastname: Carter
authors.forename: Theresa L
authors.initials: TL
authors.lastname: Powell
authors.forename: Cun
authors.initials: C
authors.lastname: Li
authors.forename: Leslie
authors.initials: L
authors.lastname: Myatt
authors.forename: Donald
authors.initials: D
authors.lastname: Dudley
authors.forename: Peter
authors.initials: P
authors.lastname: Nathanielsz
authors.forename: Thomas
authors.initials: T
authors.lastname: Jansson
mesh_terms: D000328:Adult; D002585:Cesarean Section; D005260:Female; D058975:Folate Receptor 1 / Q000378:metabolism*; D005492:Folic Acid / Q000097:blood* / Q000378:metabolism; D006801:Humans; D008871:Microvilli / Q000378:metabolism; D009765:Obesity / Q000097:blood* / Q000378:metabolism; D010920:Placenta / Q000166:cytology / Q000378:metabolism*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood* / Q000378:metabolism; D058979:Proton-Coupled Folate Transporter / Q000378:metabolism; D058978:Reduced Folate Carrier Protein / Q000378:metabolism; D047929:Term Birth / Q000378:metabolism; D014471:Umbilical Veins
chemical_list: D058975:Folate Receptor 1; D058979:Proton-Coupled Folate Transporter; D058978:Reduced Folate Carrier Protein; D005492:Folic Acid