Progesterone Receptor-mediated Coordination Of Oocyte-oviduct Communication During Ovulation
Funder
National Health and Medical Research Council
Funding Amount
$86,128.00
Summary
Infertility affects 1 in 6 couples, often due to failed release of an egg from the ovary. The hormone progesterone is essential for this process. Our goal is to determine how progesterone signals the egg to ensure its correct release into the oviduct where fertilization may occur. To identify these signals, experiments will analyse ovary cells and eggs of mice, including mice that do not respond to progesterone. The results will provide much needed information about female reproductive health.
Polycystic ovary syndrome (PCOS) affects 5-10% of women worldwide, yet its origins remain unknown. Androgens are implicated in the development of PCOS, but the decisive, invasive studies needed to confirm and elucidate their roles are not feasible in women. Hence, using our innovative mouse models of androgen resistant female mice, this study will determine the role of androgens in PCOS aiming to better understand, and identify new treatments for this common female reproductive disorder.
Immunobiology Of Early Pregnancy - A Model Of Virus-induced Abortion
Funder
National Health and Medical Research Council
Funding Amount
$454,500.00
Summary
The lack of 'self' molecule expression on the trophoblast cells of the placenta which interface directly with the mother's circulation, as well as the local suppression of the mother's immune response at this interface, may be important factors in the successful implantation of the embryo. This immunological 'silence' allows the embryo, whose paternal genetic contribution makes it immunologically foreign to the mother, to escape the rejection reaction normally associated with foreign graft trans ....The lack of 'self' molecule expression on the trophoblast cells of the placenta which interface directly with the mother's circulation, as well as the local suppression of the mother's immune response at this interface, may be important factors in the successful implantation of the embryo. This immunological 'silence' allows the embryo, whose paternal genetic contribution makes it immunologically foreign to the mother, to escape the rejection reaction normally associated with foreign graft transplantation. Infection with flaviviruses increases the concentrations of cell surface self and adhesion molecules in vertebrate cells, including the trophoblast cells of the placenta. As a result, these molecules can then be recognised by the maternal immune system and the embryo targeted for destruction. We hypothesise that the induction of these molecules by this and other viruses may break the immunological silence of the early embryo and reverse the local suppression of the maternal immune response. This would result in maternal immune rejection of the embryo and abortion. This initial sensitisation of the mother by the virus might be one of the reasons that some women suffer recurrent abortions. We will use a novel viral mouse model where we implant virus-infected embryos into receptive animals to enable us to dissect out the unusual requirements for induction of maternal anti-viral immunity during pregnancy. This model was developed in our laboratory to directly test our hypotheses. It does not cause systemic illness in the mother which itself can lead to non-specific abortion. This model therefore can for the first time elucidate the specific mechanisms associated with the delicate balance between eradicating virus and maintaining pregnancy. Results from this project will inform rational design of treatment of recurrent abortions in the community.Read moreRead less
Hormonal Control Of Serotli Cell Maturation And Function
Funder
National Health and Medical Research Council
Funding Amount
$512,898.00
Summary
This project will determine the key roles of androgen in the Sertoli cell, a unique highly specialised cell that provides essential nutritional and structural support for sperm production. Androgen acts via the androgen receptor (AR), which is vital for initiating and maintaining sperm development. In current NHMRC-funded research we successfully established new mouse models designed to study AR, in particular its regulation of gene expression, in the Sertoli cell. We revealed that genomic AR ac ....This project will determine the key roles of androgen in the Sertoli cell, a unique highly specialised cell that provides essential nutritional and structural support for sperm production. Androgen acts via the androgen receptor (AR), which is vital for initiating and maintaining sperm development. In current NHMRC-funded research we successfully established new mouse models designed to study AR, in particular its regulation of gene expression, in the Sertoli cell. We revealed that genomic AR activity within Sertoli cells is essential for 'induction' of complete sperm development. Ongoing work will develop unique 'inducible' transgenic models that will allow, for the first time, selective analysis of Sertoli AR in both 'developing' and 'adult' testes. Our innovative models will allow AR function to be switched on or off at any stage of development, providing unique opportunity to determine the key AR-regulated factors and pathways controlling induction, maintenance or restoration of sperm production. In past NHMRC research we created a novel transgenic model to study another major reproductive hormone, FSH. Using the hormone-deficient background of 'hpg' mice, we found that androgen and FSH act synergistically in the developing 'meiotic' germ cells that form sperm. Using the latest microarray gene technology we generated datasets of androgen-regulated genes with or without FSH activity, which combined with our unique transgenic AR and FSH models, will be used to identify key pathways, including those enhanced by androgen-FSH synergism, in the early testicular response. Our research will provide new knowledge of the precise roles and pathways of testicular AR actions, to ultimately identify key genetic and regulatory factors as targets for significantly improved therapy for male infertility, gonadal tumours, or contraception.Read moreRead less
This study is aiming to develop an unique mouse model in which to study the question whether testosterone plays an essential role in female reproductive and general health. It will develop a genetic mouse model for a biological state of complete resistance to the effects of androgens. Such mice and humans are well known among genetic males but this cannot occur naturally among genetic female mammals. By creating such a mouse line, this project will be able to test for the first time indetail whe ....This study is aiming to develop an unique mouse model in which to study the question whether testosterone plays an essential role in female reproductive and general health. It will develop a genetic mouse model for a biological state of complete resistance to the effects of androgens. Such mice and humans are well known among genetic males but this cannot occur naturally among genetic female mammals. By creating such a mouse line, this project will be able to test for the first time indetail whether testosterone has an impotant role in the development and function of the ovary and of other female tissues such as bone, muscle and the brain.Read moreRead less
Androgen Receptor Activity In Normal And Abnormal Human Ovarian Function
Funder
National Health and Medical Research Council
Funding Amount
$416,696.00
Summary
Androgens are hormones normally associated with men, but women also produce androgens and they are essential for normal female health and reproduction. Imbalances in female androgen activity could account for approximately 50% of female infertility, but exactly how androgens behave in women is not well understood. Making too much androgen is the most common hormonal problem experienced by women in their reproductive years, and it affects the ovary in a way that can cause infertility. Women with ....Androgens are hormones normally associated with men, but women also produce androgens and they are essential for normal female health and reproduction. Imbalances in female androgen activity could account for approximately 50% of female infertility, but exactly how androgens behave in women is not well understood. Making too much androgen is the most common hormonal problem experienced by women in their reproductive years, and it affects the ovary in a way that can cause infertility. Women with this problem have polycystic ovary syndrome (PCOS). Gaining weight increases the chance of having problems with fertility and increases the risk of diabetes and heart problems in women with PCOS. The cause of PCOS is unknown, but it can occur in families, which indicates that some genetic factor is involved. On the other hand, the concept that some women do not produce enough androgen is only beginning to emerge and remains a controversial topic among medical experts. Part of the problem with this notion is that normal female androgen levels are very difficult to measure accurately, so no one can say for certain how much is too little. A recent scientific study in female mice indicates that poor androgen action causes infertility early in life because the ovary is ageing too quickly. A similar thing could possibly occur in women, but this has never been scientifically explored. However, we have some early evidence that shows abnormally low androgen levels in infertile women with signs of early aging in the ovary. Our study aims to understand the role that androgens play in normal and abnormal ovarian function. A large part of this study involves investigation of the androgen receptor, a molecule that controls what androgens can do inside body organs. We think that abnormal activity of this receptor will be involved in ovarian diseases that cause infertility in women. This understanding may lead to new means of diagnosing and treating infertility in women.Read moreRead less