Pregnancy is associated with substantial cardiovascular adaptations including dramatically increased maternal uterine blood flow (UBF) and fetoplacental blood flows for fetal nutrient delivery. Vasodilatation and angiogenesis are the mechanisms normally controlling maternal fetal perfusion, but perfusion is reduced in pregnancies complicated by intrauterine growth restriction (IUGR). Based on the Barker hypothesis, when reaching adulthood, these IUGR/small birth weight babies exhibit a host of adult onset diseases, including hypertension and its associated morbidity. It is of great importance to understand the causes and sequelae of IUGR. Limited uterine space in multi-fetal gestations and uterine anomalies cause IUGR from uterine and placental insufficiency. We developed a novel surgically-created ovine uterine space restriction model that partially maintained UBF with placental vasculature adaptations to sustain viable fetuses with asymmetric IUGR. We propose to utilize this model to study numerous physiological processes involved in placental, fetal, and postnatal vascular development. We will test the hypotheses that during uterine space restriction, both the maternal and fetal components of the placenta (uteroplacental/fetoplacental interface) and specifically their vasculatures initially adapt to preserve sustained fetal growth through partial maintenance of rises in uterine and fetal placental blood flows (Aim I) via NO-mediated vasodilatory (Aim II) as well as VEGF- and FGF2- mediated angiogenesis (Aim III) via cell and molecular signaling mechanisms. However, with growth arrest after 0.9 gestation, both vasodilatory and angiogenic mechanisms are inadequate, leading to placental insufficiency with consequent cessation of fetal growth velocity. Because the vascular adaptations ultimately define the postnatal cardiovascular phenotype of IUGR offspring, we will test the hypothesis that the outcome is postnatal programming of hypertension (Aim IV) with dysfunctional renal development, RAS activation, and altered blood volume and pressor studies in yearling lambs.
These aims will address vascular adaptation to decreased uterine space through physiological, signaling, and molecular mechanisms of vasodilatation and angiogenesis.
Programming of adult health and disease especially conditions of angiogenic growth restriction appear to be dependent upon fetal exposure to various in utero stresses. In this proposal we present a new model of uterine space restriction and its relationship to both uterine and placental vasculature adaptations as well as developmental programming of hypertension. Developmental programming and epidemiologic data in humans and agriculturally animal species have suggested that there is specific susceptibility to hypertension and this may also be altered by gender. This current proposal will yield important information that will aid in the development of pregnancy and postnatal strategies to prevent and treat hypertension through angiogenic factor mediated mechanisms.
|Degner, Kenna; Magness, Ronald R; Shah, Dinesh M (2017) Establishment of the Human Uteroplacental Circulation: A Historical Perspective. Reprod Sci 24:753-761|
|Vargas, Vladimir E; Landeros, Rosalina Villalon; Lopez, Gladys E et al. (2017) Uterine artery leptin receptors during the ovarian cycle and pregnancy regulate angiogenesis in ovine uterine artery endothelial cells†. Biol Reprod 96:866-876|
|Kranch-Shorthouse, Rachel A; Bauer, Adam S; Magness, Ronald R et al. (2017) Ovine uterine space restriction causes dysregulation of the renin-angiotensin system in fetal kidneys. Biol Reprod 96:211-220|
|Zhou, Chi; Zou, Qing-Yun; Li, Hua et al. (2017) Preeclampsia Downregulates MicroRNAs in Fetal Endothelial Cells: Roles of miR-29a/c-3p in Endothelial Function. J Clin Endocrinol Metab 102:3470-3479|
|Pastore, Mayra B; Talwar, Saira; Conley, Meghan R et al. (2016) Identification of Differential ER-Alpha Versus ER-Beta Mediated Activation of eNOS in Ovine Uterine Artery Endothelial Cells. Biol Reprod 94:139|
|Schreier, David A; Forouzan, Omid; Hacker, Timothy A et al. (2016) Increased Red Blood Cell Stiffness Increases Pulmonary Vascular Resistance and Pulmonary Arterial Pressure. J Biomech Eng 138:021012|
|Ampey, Bryan C; Morschauser, Timothy J; Ramadoss, Jayanth et al. (2016) Domain-Specific Partitioning of Uterine Artery Endothelial Connexin43 and Caveolin-1. Hypertension 68:982-8|
|Sun, Mary Y; Woolley, Joseph C; Blohowiak, Sharon E et al. (2016) Dietary-induced gestational iron deficiency inhibits postnatal tissue iron delivery and postpones the cessation of active nephrogenesis in rats. Reprod Fertil Dev :|
|Li, Yan; Wang, Kai; Zou, Qing-Yun et al. (2015) A possible role of aryl hydrocarbon receptor in spontaneous preterm birth. Med Hypotheses 84:494-7|
|Morris, Erin A; Hale, Sarah A; Badger, Gary J et al. (2015) Pregnancy induces persistent changes in vascular compliance in primiparous women. Am J Obstet Gynecol 212:633.e1-6|
Showing the most recent 10 out of 25 publications