title: The placental pursuit for an adequate oxidant balance between the mother and the fetus.
abstract: The placenta is the exchange organ that regulates metabolic processes between the mother and her developing fetus. The adequate function of this organ is clearly vital for a physiologic gestational process and a healthy baby as final outcome. The umbilico-placental vasculature has the capacity to respond to variations in the materno-fetal milieu. Depending on the intensity and the extensity of the insult, these responses may be immediate-, mediate-, and long-lasting, deriving in potential morphostructural and functional changes later in life. These adjustments usually compensate the initial insults, but occasionally may switch to long-lasting remodeling and dysfunctional processes, arising maladaptation. One of the most challenging conditions in modern perinatology is hypoxia and oxidative stress during development, both disorders occurring in high-altitude and in low-altitude placental insufficiency. Hypoxia and oxidative stress may induce endothelial dysfunction and thus, reduction in the perfusion of the placenta and restriction in the fetal growth and development. This Review will focus on placental responses to hypoxic conditions, usually related with high-altitude and placental insufficiency, deriving in oxidative stress and vascular disorders, altering fetal and maternal health. Although day-to-day clinical practice, basic and clinical research are clearly providing evidence of the severe impact of oxygen deficiency and oxidative stress establishment during pregnancy, further research on umbilical and placental vascular function under these conditions is badly needed to clarify the myriad of questions still unsettled.
authors.affiliation: Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile ; International Center for Andean Studies, Universidad de Chile Santiago, Chile.
authors.forename: Emilio A
authors.initials: EA
authors.lastname: Herrera
authors.affiliation: División de Obstetricia y Ginecología, Facultad de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile.
authors.forename: Bernardo
authors.initials: B
authors.lastname: Krause
authors.affiliation: Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile.
authors.forename: German
authors.initials: G
authors.lastname: Ebensperger
authors.affiliation: Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile.
authors.forename: Roberto V
authors.initials: RV
authors.lastname: Reyes
authors.affiliation: División de Obstetricia y Ginecología, Facultad de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile ; División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile.
authors.forename: Paola
authors.initials: P
authors.lastname: Casanello
authors.affiliation: Unidad Materno-Fetal, Hospital Clínico Universidad de Chile, Universidad de Chile Santiago, Chile.
authors.forename: Mauro
authors.initials: M
authors.lastname: Parra-Cordero
authors.affiliation: Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile ; International Center for Andean Studies, Universidad de Chile Santiago, Chile.
authors.forename: Anibal J
authors.initials: AJ
authors.lastname: Llanos
keywords: high-altitude; hypoxia; oxidative stress; placenta; vascular dysfunction