title: Maternal environment and placental vascularization in small ruminants.
abstract: Uteroplacental development is a crucial step facilitating conceptus growth. Normal placental development comprises extensive placental angiogenesis to support fetoplacental transport, meeting the metabolic demands of the fetus. Compromised pregnancies due to maternal stressors such as over or undernutrition, maternal age or parity, altered body mass index, or genetic background result in altered vascular development of the placenta. This negatively affects placental growth and placental function and ultimately results in poor pregnancy outcomes. Nonetheless, the placenta acts as a sensor to the maternal stressors and undergoes modifications, which some have termed placental programming, to ensure healthy development of the conceptus. Sex steroid hormones such as estradiol-17β and progesterone, chemokines such as chemokine ligand 12, and angiogenic/vasoactive factors such as vascular endothelial growth factors, placental growth factor, angiopoietins, and nitric oxide regulate uteroplacental development and hence are often used as therapeutic targets to rescue compromised pregnancies. Interestingly, the presence of sex steroid receptors has been identified in the fetal membranes (developing fetal placenta). Environmental steroid mimetics known as endocrine disrupting compounds disrupt conceptus development and lead to transgenerational impairments by epigenetic modification of placental gene expression, which is another area deserving intense research efforts. This review attempts to summarize current knowledge concerning intrinsic and extrinsic factors affecting selected reproductive functions with the emphasis on placental development.
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, North Dakota, USA.
authors.forename: S
authors.initials: S
authors.lastname: Bairagi
authors.affiliation: Department of Animal and Range Sciences, New Mexico State University, Las Cruces, New Mexico, USA.
authors.forename: K E
authors.initials: KE
authors.lastname: Quinn
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, North Dakota, USA; Hettinger Research Extension Center, Hettinger, North Dakota, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: Crane
authors.affiliation: Department of Animal and Range Sciences, New Mexico State University, Las Cruces, New Mexico, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Ashley
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, North Dakota, USA.
authors.forename: P P
authors.initials: PP
authors.lastname: Borowicz
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, North Dakota, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Caton
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Department of Animal Sciences, Texas A&M University, College Station, Texas, USA.
authors.forename: R R
authors.initials: RR
authors.lastname: Redden
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, North Dakota, USA.
authors.forename: A T
authors.initials: AT
authors.lastname: Grazul-Bilska
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, North Dakota, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, North Dakota, USA. Electronic address: Larry.Reynolds@ndsu.edu.
authors.forename: L P
authors.initials: LP
authors.lastname: Reynolds
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004785:Environmental Pollutants; D005260:Female; D039382:Maternal Nutritional Physiological Phenomena; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy; D012418:Ruminants / Q000502:physiology*
chemical_list: D004785:Environmental Pollutants
keywords: Compromised pregnancy; Conceptus; Endocrine disrupting compound; Maternal stressor; Placenta; Vascular development