The Experts below are selected from a list of 186 Experts worldwide ranked by ideXlab platform

Theresa L Powell - One of the best experts on this subject based on the ideXlab platform.

  • Placental Nutrient Transport in Gestational Diabetic Pregnancies
    Frontiers in Endocrinology, 2017
    Co-Authors: Marisol Castillo-castrejon, Theresa L Powell
    Abstract:

    Maternal obesity during pregnancy is rising and is associated with increased risk of developing gestational diabetes mellitus (1). Fetal growth is determined by the maternal nutrient supply and Placental nutrient transfer capacity. GDM-complicated pregnancies are more likely to be complicated by fetal overgrowth or excess adipose deposition in utero. Infants born from GDM mothers have an increased risk of developing cardiovascular and metabolic disorders later in life. Diverse factors such as ethnicity, age, fetal sex, clinical treatment for glycemic control, gestational weight gain, body mass index among others represent a challenge for studying underlying mechanisms in GDM subjects. Determining the individual roles of glucose intolerance, obesity and other factors on Placental Function and fetal growth remains a challenge. This review provides an overview of changes in Placental macronutrient transport observed in human pregnancies complicated by GDM. Improved knowledge and understanding of the alterations in Placenta Function that lead to pathological fetal growth will allow for development of new therapeutic interventions and treatments to improve pregnancy outcomes and lifelong health for the mother and her children.

  • human Placental transport in altered fetal growth does the Placenta Function as a nutrient sensor a review
    Placenta, 2006
    Co-Authors: Thomas Jansson, Theresa L Powell
    Abstract:

    Intrauterine growth restriction is associated with a range of alterations in Placental transport Functions: the activity of a number of transporters is reduced (Systems A, L and Tau, transporters for cationic amino acids, the sodium-proton exchanger and the sodium pump), Placental glucose transporter activity and expression are unchanged whereas the activity of the calcium pump is increased. In contrast, accelerated fetal growth in association to diabetes is characterized by increased activity of Placental Systems A and L and glucose transporters. Evidence suggests that these Placental transport alterations are the result of specific regulation and that they, at least in part, contribute to the development of pathological fetal growth rather than representing a consequence to altered fetal growth. One interpretation of this data is that the Placenta Functions as a nutrient sensor, altering Placental transport Functions according to the ability of the maternal supply line to provide nutrients. Placental transporters are subjected to regulation by hormones. Insulin up-regulates several key Placental transporters and maternal insulin may represent a "good nutrition" signal to increase Placental nutrient transfer and the growth of the fetus. Preliminary evidence suggests that Placental mammalian target of rapamycin, a protein kinase regulating protein translation and transcription in response to nutrient stimuli, may be involved in Placental nutrient sensing.

  • IFPA 2005 Award in Placentology Lecture. Human Placental transport in altered fetal growth: does the Placenta Function as a nutrient sensor? -- a review.
    Placenta, 2006
    Co-Authors: Thomas Jansson, Theresa L Powell
    Abstract:

    Intrauterine growth restriction is associated with a range of alterations in Placental transport Functions: the activity of a number of transporters is reduced (Systems A, L and Tau, transporters for cationic amino acids, the sodium-proton exchanger and the sodium pump), Placental glucose transporter activity and expression are unchanged whereas the activity of the calcium pump is increased. In contrast, accelerated fetal growth in association to diabetes is characterized by increased activity of Placental Systems A and L and glucose transporters. Evidence suggests that these Placental transport alterations are the result of specific regulation and that they, at least in part, contribute to the development of pathological fetal growth rather than representing a consequence to altered fetal growth. One interpretation of this data is that the Placenta Functions as a nutrient sensor, altering Placental transport Functions according to the ability of the maternal supply line to provide nutrients. Placental transporters are subjected to regulation by hormones. Insulin up-regulates several key Placental transporters and maternal insulin may represent a "good nutrition" signal to increase Placental nutrient transfer and the growth of the fetus. Preliminary evidence suggests that Placental mammalian target of rapamycin, a protein kinase regulating protein translation and transcription in response to nutrient stimuli, may be involved in Placental nutrient sensing.

Thomas Jansson - One of the best experts on this subject based on the ideXlab platform.

  • human Placental transport in altered fetal growth does the Placenta Function as a nutrient sensor a review
    Placenta, 2006
    Co-Authors: Thomas Jansson, Theresa L Powell
    Abstract:

    Intrauterine growth restriction is associated with a range of alterations in Placental transport Functions: the activity of a number of transporters is reduced (Systems A, L and Tau, transporters for cationic amino acids, the sodium-proton exchanger and the sodium pump), Placental glucose transporter activity and expression are unchanged whereas the activity of the calcium pump is increased. In contrast, accelerated fetal growth in association to diabetes is characterized by increased activity of Placental Systems A and L and glucose transporters. Evidence suggests that these Placental transport alterations are the result of specific regulation and that they, at least in part, contribute to the development of pathological fetal growth rather than representing a consequence to altered fetal growth. One interpretation of this data is that the Placenta Functions as a nutrient sensor, altering Placental transport Functions according to the ability of the maternal supply line to provide nutrients. Placental transporters are subjected to regulation by hormones. Insulin up-regulates several key Placental transporters and maternal insulin may represent a "good nutrition" signal to increase Placental nutrient transfer and the growth of the fetus. Preliminary evidence suggests that Placental mammalian target of rapamycin, a protein kinase regulating protein translation and transcription in response to nutrient stimuli, may be involved in Placental nutrient sensing.

  • IFPA 2005 Award in Placentology Lecture. Human Placental transport in altered fetal growth: does the Placenta Function as a nutrient sensor? -- a review.
    Placenta, 2006
    Co-Authors: Thomas Jansson, Theresa L Powell
    Abstract:

    Intrauterine growth restriction is associated with a range of alterations in Placental transport Functions: the activity of a number of transporters is reduced (Systems A, L and Tau, transporters for cationic amino acids, the sodium-proton exchanger and the sodium pump), Placental glucose transporter activity and expression are unchanged whereas the activity of the calcium pump is increased. In contrast, accelerated fetal growth in association to diabetes is characterized by increased activity of Placental Systems A and L and glucose transporters. Evidence suggests that these Placental transport alterations are the result of specific regulation and that they, at least in part, contribute to the development of pathological fetal growth rather than representing a consequence to altered fetal growth. One interpretation of this data is that the Placenta Functions as a nutrient sensor, altering Placental transport Functions according to the ability of the maternal supply line to provide nutrients. Placental transporters are subjected to regulation by hormones. Insulin up-regulates several key Placental transporters and maternal insulin may represent a "good nutrition" signal to increase Placental nutrient transfer and the growth of the fetus. Preliminary evidence suggests that Placental mammalian target of rapamycin, a protein kinase regulating protein translation and transcription in response to nutrient stimuli, may be involved in Placental nutrient sensing.

Yan Zhong - One of the best experts on this subject based on the ideXlab platform.

  • first trimester assessment of Placenta Function and the prediction of preeclampsia and intrauterine growth restriction
    Prenatal Diagnosis, 2010
    Co-Authors: Yan Zhong, Methodius G Tuuli, Anthony Odibo
    Abstract:

    Preeclampsia and intrauterine growth restriction (IUGR) are major contributors to perinatal mortality and morbidity worldwide. Both are characterized by impaired trophoblastic invasion of the maternal spiral arteries and their conversion from narrow muscular vessels to wide non-muscular channels. Despite improvement in the understanding of the pathophysiology of these conditions, ability to accurately identify pregnant woman who will develop them is limited. This greatly impairs the development and testing of preventive interventions. While different measures of Placental dysFunction have been associated with increased risk for adverse pregnancy outcomes, the ability of any single one to accurately predict these outcomes is poor. Developing predictive tests is further challenged by difficulty in the timing of the measurements, as both the structural and biochemical characteristics of the Placenta change with increasing gestational age. The ideal screening test would accurately predict the development of adverse pregnancy outcomes early enough to provide a window for preventive interventions. Improvement in ultrasound technology provides potentially useful novel tools for evaluating Placental structure, but measuresments need to be standardized in order to be useful. Maternal serum analyte screening is a noninvasive test of Placental biochemical Function, but present serum marker alone is not sufficiently accurate to suggest its routine use in clinical practice. The use of first trimester biochemical markers in combination with uterine artery Doppler screening is promising as a potential screening tool. Prospective longitudinal studies using standardized methodology are necessary to further evaluate the choice of parameters and strategies of combination to achieve the best predictive models. Copyright © 2010 John Wiley & Sons, Ltd.

Anthony Odibo - One of the best experts on this subject based on the ideXlab platform.

  • first trimester assessment of Placenta Function and the prediction of preeclampsia and intrauterine growth restriction
    Prenatal Diagnosis, 2010
    Co-Authors: Yan Zhong, Methodius G Tuuli, Anthony Odibo
    Abstract:

    Preeclampsia and intrauterine growth restriction (IUGR) are major contributors to perinatal mortality and morbidity worldwide. Both are characterized by impaired trophoblastic invasion of the maternal spiral arteries and their conversion from narrow muscular vessels to wide non-muscular channels. Despite improvement in the understanding of the pathophysiology of these conditions, ability to accurately identify pregnant woman who will develop them is limited. This greatly impairs the development and testing of preventive interventions. While different measures of Placental dysFunction have been associated with increased risk for adverse pregnancy outcomes, the ability of any single one to accurately predict these outcomes is poor. Developing predictive tests is further challenged by difficulty in the timing of the measurements, as both the structural and biochemical characteristics of the Placenta change with increasing gestational age. The ideal screening test would accurately predict the development of adverse pregnancy outcomes early enough to provide a window for preventive interventions. Improvement in ultrasound technology provides potentially useful novel tools for evaluating Placental structure, but measuresments need to be standardized in order to be useful. Maternal serum analyte screening is a noninvasive test of Placental biochemical Function, but present serum marker alone is not sufficiently accurate to suggest its routine use in clinical practice. The use of first trimester biochemical markers in combination with uterine artery Doppler screening is promising as a potential screening tool. Prospective longitudinal studies using standardized methodology are necessary to further evaluate the choice of parameters and strategies of combination to achieve the best predictive models. Copyright © 2010 John Wiley & Sons, Ltd.

Wangming Xu - One of the best experts on this subject based on the ideXlab platform.

  • oxidative stress Placenta Function and dysFunction
    American Journal of Reproductive Immunology, 2016
    Co-Authors: Fan Wu, Fuju Tian, Wangming Xu
    Abstract:

    During pregnancy, the Placenta is a site of active oxygen metabolism that continuously generates oxidative stress (OS). Overproduction of reactive oxygen species and reactive nitrogen species can destroy normal Placental Functions. Therefore, the feto-Placental unit generates abundant antioxidants to keep OS under control. Properly controlled oxidative species have been proven to serve as indispensable cellular signal messengers by regulating gene expression and downstream cellular activities. OS also plays an important immunoregulatory role during pregnancy. Oxidative disorder and immune disturbances are associated with adverse pregnancy outcomes such as spontaneous abortion, preeclampsia and intrauterine growth restriction. In this review, we introduce recent studies revealing basal Functions and regulatory roles of Placental OS in metabolism and immunity. The relationships between OS- and pregnancy-related disorders are also discussed.