title: The cumulative effect of assisted reproduction procedures on placental development and epigenetic perturbations in a mouse model.
abstract: Assisted reproductive technologies (ART) are associated with several complications including low birth weight, abnormal placentation and increased risk for rare imprinting disorders. Indeed, experimental studies demonstrate ART procedures independent of existing infertility induce epigenetic perturbations in the embryo and extraembryonic tissues. To test the hypothesis that these epigenetic perturbations persist and result in adverse outcomes at term, we assessed placental morphology and methylation profiles in E18.5 mouse concepti generated by in vitro fertilization (IVF) in two different genetic backgrounds. We also examined embryo transfer (ET) and superovulation procedures to ascertain if they contribute to developmental and epigenetic effects. Increased placental weight and reduced fetal-to-placental weight ratio were observed in all ART groups when compared with naturally conceived controls, demonstrating that non-surgical embryo transfer alone can impact placental development. Furthermore, superovulation further induced overgrowth of the placental junctional zone. Embryo transfer and superovulation defects were limited to these morphological changes, as we did not observe any differences in epigenetic profiles. IVF placentae, however, displayed hypomethylation of imprinting control regions of select imprinted genes and a global reduction in DNA methylation levels. Although we did not detect significant differences in DNA methylation in fetal brain or liver samples, rare IVF concepti displayed very low methylation and abnormal gene expression from the normally repressed allele. Our findings suggest that individual ART procedures cumulatively increase placental morphological abnormalities and epigenetic perturbations, potentially causing adverse neonatal and long-term health outcomes in offspring.
authors.affiliation: Department of Cell and Developmental Biology.
authors.forename: Eric
authors.initials: E
authors.lastname: de Waal
authors.affiliation: Department of Cell and Developmental Biology.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Vrooman
authors.affiliation: Department of Cell and Developmental Biology.
authors.forename: Erin
authors.initials: E
authors.lastname: Fischer
authors.affiliation: Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA and.
authors.forename: Teri
authors.initials: T
authors.lastname: Ord
authors.affiliation: Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA and.
authors.forename: Monica A
authors.initials: MA
authors.lastname: Mainigi
authors.affiliation: Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA and.
authors.forename: Christos
authors.initials: C
authors.lastname: Coutifaris
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Schultz
authors.affiliation: Department of Cell and Developmental Biology, bartolom@mail.med.upenn.edu.
authors.forename: Marisa S
authors.initials: MS
authors.lastname: Bartolomei
mesh_terms: D000483:Alleles; D026924:Amino Acid Transport System A / Q000378:metabolism; D000818:Animals; D003433:Crosses, Genetic; D019175:DNA Methylation; D004624:Embryo Transfer / Q000009:adverse effects; D057890:Epigenomics; D005260:Female; D005307:Fertilization in Vitro / Q000009:adverse effects; D005333:Fetus / Q000378:metabolism; D015870:Gene Expression; D051272:Glucose Transporter Type 1 / Q000378:metabolism; D051274:Glucose Transporter Type 3 / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010062:Ovulation Induction / Q000009:adverse effects; D010920:Placenta / Q000378:metabolism / Q000473:pathology; D010929:Placentation; D011247:Pregnancy; D011256:Pregnancy Outcome; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects*
chemical_list: D026924:Amino Acid Transport System A; D051272:Glucose Transporter Type 1; D051274:Glucose Transporter Type 3; C495678:Slc2a1 protein, mouse; C495689:Slc2a3 protein, mouse; C498798:Slc38a2 protein, mouse; C420522:Slc38a4 protein, mouse