title: Placental heme receptor LRP1 correlates with the heme exporter FLVCR1 and neonatal iron status.
abstract: LDL receptor-related protein 1 (LRP1) is a transmembrane receptor highly expressed in human placenta. It was recently found to be the receptor for heme and its plasma-binding protein hemopexin (Hx) and is integral to systemic heme clearance. Little is known about systemic concentrations of Hx during pregnancy and whether maternal Hx and placental LRP1 contributes to fetal iron (Fe) homeostasis during pregnancy. We hypothesized that placental LRP1 would be upregulated in maternal/neonatal Fe insufficiency and would be related to maternal circulating Hx. Placental LRP1 expression was assessed in 57 pregnant adolescents (14-18 years) in relationship with maternal and cord blood Fe status indicators (hemoglobin (Hb), serum ferritin, transferrin receptor), the Fe regulatory hormone hepcidin and serum Hx. Hx at mid-gestation correlated positively with Hb at mid-gestation (r=0.35, P=0.02) and Hx at delivery correlated positively with cord hepcidin (r=0.37, P=0.005). Placental LRP1 protein expression was significantly higher in women who exhibited greater decreases in serum Hx from mid-gestation to term (r=0.28, P=0.04). Significant associations were also found between placental LRP1 protein with cord hepcidin (r=-0.29, P=0.03) and placental heme exporter feline leukemia virus C receptor 1 (r=0.34, P=0.03). Our data are consistent with a role for placental heme Fe utilization in supporting fetal Fe demands.
authors.affiliation: Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA.
authors.forename: Chang
authors.initials: C
authors.lastname: Cao
authors.affiliation: Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA.
authors.forename: Eva K
authors.initials: EK
authors.lastname: Pressman
authors.affiliation: Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Cooper
authors.affiliation: Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA.
authors.forename: Ronnie
authors.initials: R
authors.lastname: Guillet
authors.affiliation: Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Westerman
authors.affiliation: Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA koo4@cornell.edu.
authors.forename: Kimberly O
authors.initials: KO
authors.lastname: O'Brien
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D005260:Female; D005293:Ferritins / Q000097:blood; D005312:Fetal Blood; D006454:Hemoglobins / Q000378:metabolism; D006466:Hemopexin / Q000378:metabolism*; D064451:Hepcidins / Q000097:blood; D006706:Homeostasis; D006801:Humans; D007501:Iron / Q000097:blood / Q000378:metabolism*; D026503:Low Density Lipoprotein Receptor-Related Protein-1 / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011446:Prospective Studies; D011990:Receptors, Transferrin / Q000097:blood; D011991:Receptors, Virus / Q000235:genetics / Q000378:metabolism*
chemical_list: D015415:Biomarkers; C492690:FLVCR1 protein, human; D006454:Hemoglobins; D064451:Hepcidins; C475476:LRP1 protein, human; D026503:Low Density Lipoprotein Receptor-Related Protein-1; D026901:Membrane Transport Proteins; D011990:Receptors, Transferrin; D011991:Receptors, Virus; D005293:Ferritins; D006466:Hemopexin; D007501:Iron