The Role Of Placental Transcription Factors In The Pathogenesis Of Fetal Growth Restriction
Funder
National Health and Medical Research Council
Funding Amount
$601,582.00
Summary
We must understand the role of growth control genes in the growth of the human placenta. The reason is that in several significant placental disorders, placental formation is abnormal and prevents the placenta from functioning efficiently. This in turn, impacts on the growth of the developning fetus. A variety of established and innovative methods described in this project will determine the functions of the placental growth control genes and may lead to novel therapeutic targets.
Prevention Of Placental Oxidative Stress And Inflammation By Dietary Omega-3 Fatty Acids
Funder
National Health and Medical Research Council
Funding Amount
$547,970.00
Summary
Several pregnancy disorders that result in low birthweight involve aberrant function of the placenta. In this project we will examine one of the key mechanisms underlying placental dysfunction, namely oxidative stress, and determine whether its adverse effects can be limited by supplementation with dietary omega 3 fatty acids. The outcomes of this project will help guide future clinical studies on the possible beneficial effects of omega-3 fatty acids in pregnancy.
P-glycoprotein: A New Player In The Placental Glucocorticoid Barrier
Funder
National Health and Medical Research Council
Funding Amount
$424,711.00
Summary
Adequate growth and development of the fetus are crucial for survival of the newborn. The placenta plays a central role in these processes, providing the fetus with appropriate nutrients and hormonal signals. The placenta also regulates the maternal-fetal passage of hormones, some of which have the capacity to limit fetal growth. These include glucocorticoid hormones from the mother's adrenal gland (eg cortisol) which are normally prevented from passing through the placenta to the fetus due to t ....Adequate growth and development of the fetus are crucial for survival of the newborn. The placenta plays a central role in these processes, providing the fetus with appropriate nutrients and hormonal signals. The placenta also regulates the maternal-fetal passage of hormones, some of which have the capacity to limit fetal growth. These include glucocorticoid hormones from the mother's adrenal gland (eg cortisol) which are normally prevented from passing through the placenta to the fetus due to the 'placental glucocorticoid barrier'. The primary focus of this proposal is the investigation of a potential new contributor to this barrier called P-glycoprotein (P-gp), recently shown to limit access of glucocorticoids to the brain. We propose that because the placenta expresses significant amounts of P-gp, it may help prevent maternal glucocorticoids from reaching the fetus and causing growth retardation. We will determine whether P-gp is a significant contributor to the placental glucocorticoid barrier, and measure how much P-gp is present in normal placentas throughout pregnancy. We will also assess whether there is less P-gp present in placentas of growth-retarded fetuses. Understanding how P-gp affects the passage of glucocorticoids across the placenta could help to treat certain cases of fetal growth retardation.Read moreRead less
Oxygen, Oxidative Phosphorylation And Regulation Of Embryo Development.
Funder
National Health and Medical Research Council
Funding Amount
$141,096.00
Summary
There is concern that human infertility treatment requiring the growth of embryos in the laboratory, as applied in human IVF, may cause problems during fetal development or even possibly lead to health problems much later in life as an adult. In particular, many clinics are now growing human embryos outside the body for several days longer (to select the best embryos for transfer) than what occurred a decade ago. This concern is based on the evidence that the environment in which an embryo grows ....There is concern that human infertility treatment requiring the growth of embryos in the laboratory, as applied in human IVF, may cause problems during fetal development or even possibly lead to health problems much later in life as an adult. In particular, many clinics are now growing human embryos outside the body for several days longer (to select the best embryos for transfer) than what occurred a decade ago. This concern is based on the evidence that the environment in which an embryo grows in has an impact on the way in which some genes are switched on and off. Normal on-off switching at appropriate times during early development should lead to healthy offspring. Failure to turn off or on, or inappropriate timing, may lead to consequences that manifest themselves later in development. We believe that oxygen concentration and the activity of mitochondria, the organelles of cells that converts oxygen into energy, are key regulators in turning on and off genes during early embryo development. This is because we have shown that, in embryos of a species that is metabolically similar to the human embryo, oxygen concentration and mitochondria activity need to change as the embryo grows for optimal development in the laboratory. In other mammalian cells, oxygen and mitochondria activity are known to turn on or off several particular genes, known as transcription factors. Transcription factors are genes which regulate other genes. Therefore, transcription factors are good candidates as regulators of early embryo development. The present project aims to determine if factors such as changing oxygen concentration and mitochondria activity during laboratory growth of embryos affects the way in which these transcription factors turn on and off. If we find this is true, the way in which human embryos are grown in the laboratory needs to be examined carefully to minimize the risk of possible long-term consequences to the resulting fetus.Read moreRead less
Identification Of Factors Essential For Oocyte Viability
Funder
National Health and Medical Research Council
Funding Amount
$220,500.00
Summary
Approximately 2% Australia children are now conceived using in vitro fertilisation technologies, allowing infertile couples to bear their own children. However, a major consequence of IVF techniques is multiple pregnancies (i.e. twins and triplets) which is a major health risk to mothers and their infants. Furthemore, IVF increases birth defects, which are mostly attributed to the increased multiple pregnancies, but is also observed in pregnancies involving a single infant. It is essential that ....Approximately 2% Australia children are now conceived using in vitro fertilisation technologies, allowing infertile couples to bear their own children. However, a major consequence of IVF techniques is multiple pregnancies (i.e. twins and triplets) which is a major health risk to mothers and their infants. Furthemore, IVF increases birth defects, which are mostly attributed to the increased multiple pregnancies, but is also observed in pregnancies involving a single infant. It is essential that IVF techniques are developed that enables the transfer of a single embryo to the mother resulting in the birth of a single healthy baby, without the ethical concerns of surplus embryo disposal. Women receiving IVF are required to adminster hormones that stimulate the eggs in their ovaries to mature to the point where they can be fertilised by their partner's sperm. These hormones, called gonadotrophins, override the body's own ovarian stimulating system and cause many eggs to mature and be collected for fertilisation, instead of normally just one. In this way, the best embryo(s) can be selected for transfer back to the mother, and other embryos can be frozen and stored for later use. However, large doses of gonadotrophins has consequences. They can be dangerous to some patients who are sensitive to their potency, and stimulate a massive response. They also reduce the quality of eggs and subsequent embryos, which reduces the chances of a pregnancy. All this can be avoided if eggs can be collected from ovaries in an immature state and maturation achieved in the laboratory. However, although attempted, this has not been a successful technique, primarily because we don't understand the process of human egg maturation. Our research will investigate the biochemistry, physiology and genetics of non-human eggs and embryos resulting from eggs that are grown and matured in the laboratory, to develop techniques for the successful maturation of human eggs in the laboratory.Read moreRead less
This study aims to determine the extent to which semen is important in initiating the maternal immune response to the fetus and placenta during pregnancy. We postulate that exposure to paternal proteins in sperm and other factors present in the semen may have a cumulative, beneficial effect in 'educating' the female immune system to respond in the correct way to the embryo when pregnancy occurs. To investigate this, the behaviour and movements of white blood cells responding to semen will be stu ....This study aims to determine the extent to which semen is important in initiating the maternal immune response to the fetus and placenta during pregnancy. We postulate that exposure to paternal proteins in sperm and other factors present in the semen may have a cumulative, beneficial effect in 'educating' the female immune system to respond in the correct way to the embryo when pregnancy occurs. To investigate this, the behaviour and movements of white blood cells responding to semen will be studied during the period after mating, in which the uterus prepares for and accommodates to pregnancy. In particular, the study will focus on the roles of a specific chemical messenger substance in semen, called transforming growth factor (TGF)-beta, which triggers the molecular changes leading to maternal immune tolerance. A deeper understanding of these events will have an important impact in human and veterinary medicine where implantation failure is a major cause of reproductive loss and inadequate placental growth poses a threat to the health of the conceptus both in utero and into adult life.Read moreRead less
Why Is Trophoblast Invasion Defective In Human Pregnancies That Develop Pre-eclampsia
Funder
National Health and Medical Research Council
Funding Amount
$504,500.00
Summary
Pre-eclampsia is the most common serious medical disorder of otherwise healthy young pregnant women. Early in pregnancies destined for pre-eclampsia, placental cells (cytotrophoblasts) do not invade deeply enough into maternal blood vessels within the uterus, with resultant low oxygen levels and reduced blood flow from the mother's circulation to placenta. This causes fetal under-nutrition and growth restriction, which if severe, can cause intrauterine death. To prevent this, the baby may need t ....Pre-eclampsia is the most common serious medical disorder of otherwise healthy young pregnant women. Early in pregnancies destined for pre-eclampsia, placental cells (cytotrophoblasts) do not invade deeply enough into maternal blood vessels within the uterus, with resultant low oxygen levels and reduced blood flow from the mother's circulation to placenta. This causes fetal under-nutrition and growth restriction, which if severe, can cause intrauterine death. To prevent this, the baby may need to be delivered prematurely, with grave risks of complications, both short and longterm. Women with pre-elampsia suffer from hypertension, activation of the clotting system, and generalized constriction of blood vessels. Together, these result in damage to blood vessel lining cells, reduced blood flow to, and disturbed function of many organs. Most commonly affected are kidney, liver, brain, and the uterine circulation. Babies born early and-or small-for-gestational-age have an increased incidence of vascular disease, hypertension, diabetes and kidney disease in adult life. Improved understanding, and development of preventive and-or therapeutic strategies for pre-eclampsia are urgently needed. There is no satisfactory animal model to address pathogenesis of this peculiarly human disorder, which concurrently causes significant morbidity in two generations of people. Ethical constraints and the need for urgent therapy limit extensive research in affected pregnant women. With our unique in vitro cell co-culture strategy, we have clarified inter-relationships between fetal-placental cells (cytotrophoblasts) and their host maternal vascular cells (decidual endothelial cells) in the clinical syndrome of pre-eclampsia. Building on this work we will now examine maternal-placental intercellular cooperation in regulation of normal placental development, and explore the defective regulation of placental development that precedes pre-eclampsia.Read moreRead less